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Specialty oils and fats in confectionery
Specialty oils and fats in confectionery
9
G. Talbot The Fat Consultant, Bedford, UK
Abbreviations A Li Ln O P S St U
arachidic acid (C20:0) linoleic acid (C18:2) linolenic acid (C18:3) oleic acid (C18:1) palmitic acid (C16:0) total saturates stearic acid (C18:0) total unsaturates
9.1 Introduction The term confectionery can cover a wide range of food products, some of which are being covered in other chapters in this book. For example, ice cream can come under the category of “frozen confectionery” and this is discussed in Chapter 11. Many bakery products, particularly sweet bakery products such as biscuits, cakes, and patisserie, are also sometimes referred to as confectionery. The types of confectionery that will be considered in this chapter are ambient-stable, often chocolate-based confectionery products. Clearly, not all of the types of oils considered in the first part of this book are used in these types of confectionery products. There is little, if any, use of olive oil, for example, in chocolate confectionery products; oils such as flaxseed oil or hemp oil have minimal applications in these products, as do algal oils. On the other hand, tropical exotic oils, including shea butter and its derivatives, have a widespread use in chocolate confectionery; tree nuts are often used as inclusions in chocolate confectionery and tree nut butters are the basis of many truffle centers. Although not considered specifically in the first part of the book, essential oils such as mint oil, orange, and lemon oils have a flavoring role in confectionery. Finally, structured triglycerides have been and still are used in a number of very specific applications in confectionery. It is the use of these types of oils that will be the main focus of this chapter.
Specialty Oils and Fats in Food and Nutrition. http://dx.doi.org/10.1016/B978-1-78242-376-8.00009-0 © 2015 Elsevier Ltd. All rights reserved.
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9.2 Cocoa butter In terms of the fats used, the basis of almost all chocolate confectionery is cocoa butter. Cocoa butter itself has not been a focus in this book because it is considered to be more of a commodity fat than a specialty fat. This, though, is a consideration based mainly on trade and availability of cocoa butter (although there are some years when the availability is more limited and the price increases dramatically, potentially pushing it into the specialty area). If, though, we base the definition of specialty or commodity on chemical composition, physical characteristics, and application, then cocoa butter does fall into the category of being a specialty fat. Because much of the use of tropical exotic oils and some structured triglycerides in confectionery are based on matching physical characteristics to those of cocoa butter, cocoa butter itself is a good place to start. Cocoa butter is extracted from the beans (seeds) of the Theobroma cacao tree (Beckett, 2009). The tree produces pods that contain these beans. Cocoa is grown in a region between 10° and 20° north and south of the equator and is, therefore, found in three main geographical regions: Central and South America, West Africa, and Southeast Asia (largely, Malaysia and Indonesia). Cocoa butter has a very specific fatty acid and triglyceride composition and it is this that gives it its very specific physical characteristics that make it so useful as a base for confectionery. Add to that the distinctive flavor of both cocoa butter and cocoa powder and it becomes very clear why chocolate is a product liked the world over. Cocoa butter is mainly composed of three fatty acids—palmitic (C16:0), stearic (C18:0), and oleic (C18:1)—together with low levels of linoleic acid (C18:2) and arachidic acid (C20:0). The relative levels of these fatty acids differ from origin to origin (Figure 9.1) with South American (Brazilian) cocoa butter containing higher levels of unsaturated fatty acids than cocoa butters from other growing regions, and Asian (Malaysian) cocoa butter containing less palmitic acid and more stearic acid than cocoa butter from West Africa (Ivory Coast). These fatty acids translate then into different triglyceride compositions with South American cocoa butters containing higher levels of unsaturated triglycerides such as SLiS and SOO, and Asian cocoa butters containing higher levels of POSt and StOSt (Figure 9.2). These differences in fatty acid and triglyceride composition result in significant differences in the solid fat contents and melting profiles of cocoa butters from different origins (Figure 9.3). The very specific triglyceride composition of cocoa butter, particularly its high level of total SOS triglycerides, means that cocoa butter is a highly polymorphic fat. In other words, it is a fat that can crystallize in a number of different polymorphic, or crystal, forms. In general, fats can crystallize in three basic polymorphic forms— alpha (α), beta-prime (β′), and beta (β)—although forms of lower stability than these three—gamma (γ) and delta (δ)—have also been observed. The polymorphism of fats, with particular reference to cocoa butter, is described in more detail by Talbot (2009a, pp. 57–61). Essentially, cocoa butter can crystallize in up to six different polymorphic forms; despite extensive research, the exact number, five or six, is still the subject of much debate. These different polymorphic forms have different stabilities and
Specialty oils and fats in confectionery223 40 35 30 25 20 15 10 5 0 C16:0
C18:0 Brazil
C18:1
Ivory Coast
C18:2
Malaysia
Figure 9.1 Fatty acid compositions of cocoa butter of different origins. Taken from Lipp and Anklam (1998) and Talbot (2009a). 45 40 35 30 25 20 15 10 5 0 POP
POSt S. America
StOSt Africa
SLiS + SOO
Asia
Figure 9.2 Triglyceride compositions of cocoa butter of different origins. Taken from Chaiseri and Dimick (1989) and Talbot (2009a).
d ifferent melting points. The most stable are two slightly different β forms. Early work by Wille and Lutton (1966) on which much of the nomenclature of these forms is based identified six forms called Forms I–VI, with Form VI being the most stable and the highest melting. Because both of the most stable forms are β forms they are now often referred to as βV and βVI.
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% Solid fat (by NMR)
80 70 60 50 40 30 20 10 0 15
20
Malaysian
25 30 Temperature ( C) West African
35
40
Brazilian
Based on information from Loders Croklaan, undated
Figure 9.3 Melting profiles of cocoa butters of different origins.
When it is being processed in chocolate, it is necessary to ensure that cocoa butter crystallizes in one of these stable β forms and in order to ensure that this happens, chocolate goes through a process of tempering. The science of tempering is described in detail by Smith (2009) and the process itself by Richter (2009). In summary, though, chocolate is cooled from a molten state at about 45–50 °C to a temperature of about 24–28 °C (so that some crystallization of cocoa butter can be initiated in a reasonable time frame) and then reheated to a temperature of about 27–33 °C. The actual temperatures used depend on the composition of the chocolate (the origin of the cocoa butter, the amount of milk fat used in a milk chocolate, the nature of any vegetable fat added to the chocolate). When the chocolate is cooled to 24–28 °C, both stable βV crystals and unstable β′ (Form IV) crystals are produced. The unstable crystals are not wanted (and if they are retained will adversely affect the quality of the end chocolate) and so the temperature of the chocolate is raised to a point above the melting point of the β′ crystals but still below the melting point of βV crystals. This then leaves only βV crystals. Even in a well-tempered chocolate the level of βV crystals present is very low (typically about 1%) but it is high enough to then “seed” the crystallization of the remaining cocoa butter in this same crystal form when the chocolate is cooled more rapidly in a cooling tunnel. The βV crystals present in well-tempered chocolate are not in the most stable polymorphic form—this is the βVI form. It is, though, not possible (with current technology, at least) for cocoa butter in chocolate to crystallize directly in the βVI crystal form. Indeed, once a chocolate has been well tempered and crystallized into the βV form it is beneficial to try to keep the cocoa butter in that form because transformation on storage into the βVI form is often accompanied by the formation of a whitish film of fat bloom on the surface of the chocolate.
Specialty oils and fats in confectionery225
Because of the high and fluctuating price of cocoa butter, fat processors have developed various types of cocoa butter alternative. These have mainly been developed as cheaper alternatives to chocolate and so one of the main requirements has been that they should melt in a similar way to cocoa butter so that any coatings based on the alternative match chocolate in that regard. This can be achieved from a variety of fats but some not only match the melting profile of cocoa butter they also are a good match to the triglyceride composition of cocoa butter. These require the use of tropical exotic oils for their production.
9.3 Use of tropical exotic oils (including derivatives of shea butter) in coatings There are three basic types of cocoa butter alternative: ●
●
●
cocoa butter equivalents (CBEs), cocoa butter replacers (CBRs), and cocoa butter substitutes (CBSs).
CBSs are based on lauric fats, that is, fats that are rich in lauric acid (C12:0). In commercial terms there are only two lauric fats of any significance for use in this type of application: palm kernel oil and coconut oil. Palm kernel oil is derived, along with palm oil, from the oil palm, Elaeis guineensis and Elaeis olifera. In the context of which are specialty and which are commodity oils, both palm oil and palm kernel oil are considered to be commodities and are therefore not being considered in any detail in this book. Coconut oil is on the cusp between commodity and specialty but has been included in this book and its characteristics are described in detail in Section 4.11. In their basic, unprocessed forms both palm kernel oil and coconut oil are too soft for use as an alternative to cocoa butter in ambient confectionery coatings. They can, though, both be used in ice cream coatings (see Chapter 11). Palm kernel oil, when fractionated, gives a stearine that has solid fat contents that are suitable for use in a CBS. Despite similarities in their basic oil forms, coconut oil, when fractionated, is still too soft for use in a confectionery coating on ambient confectionery. For this reason, coconut oil will not be considered in this application, but will be discussed later in this chapter as a base for confectionery fillings. CBRs have traditionally been based on partially hydrogenated and fractionated combinations of palm oil, soyabean oil, cottonseed oil, and rapeseed oil. Since the decline in the use of hydrogenation as an oil modification process, CBRs have largely been produced from fractions of palm oil. Other than in the area of modified traits (see Chapter 7), none of these oils can be considered to be specialty oils and so the area of CBRs will also not be considered further in this chapter. Readers who want to know more about both CBS and CBR cocoa butter alternatives are directed to Talbot (2009b). This then leaves only CBEs, and it is in this type of product that tropical exotic oils really come into widespread use. In this context, not only will many of the tropical exotic oils described in Chapter 4 be considered but also oils derived from shea butter
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(Chapter 5) as perhaps the most important specialty component in CBEs. CBEs are vegetable fats that not only melt in the same way as does cocoa butter but, unlike CBSs and CBRs, they also are composed of the same types of symmetrical monounsaturated triglycerides (SOS) as are found in cocoa butter itself. Hence, they are equivalent to cocoa butter in all senses—composition, melting, crystallization, polymorphism, need for tempering, and so on. Although they are usually referred to as CBEs, these fats have a much broader spectrum than simply being equivalent to cocoa butter. Some do match the properties of cocoa butter extremely well, but others are softer than cocoa butter and have been used, not so much to replace some of the cocoa butter in chocolate but some of the milk fat as well. This has been done particularly at times when cocoa butter has been relatively low in price and milk fat higher in price. Other vegetable fats are harder and higher melting than cocoa butter and are often referred to as cocoa butter improvers (CBIs). These are used for a variety of reasons: they produce a more heat-resistant chocolate for warmer countries; they produce a more bloom-resistant chocolate; and they are more resistant to the effects of oil migration from a soft filling. Whatever label may be put on them—CBE, milk fat replacers (MFR), CBI, etc.—they are all vegetable fats and so their use in chocolate is subject to national legislation on the use of vegetable fats in chocolate. Perhaps the most detailed legislation on the use of vegetable fats in chocolate is that of the European Union (2000). Many other countries also have legislation to allow the use of vegetable fats in chocolate but, unlike the European Union (EU) legislation, most simply limit the amount of vegetable fat that can be used without putting any limitations on the types of fat that can be used. Other countries, such as the United States, do not allow vegetable fats to be used in products labeled “chocolate.” The European Union, though, put restrictions on the types of vegetable fat that can be used and the ways in which that fat can be processed. In terms of its type, the fats used can be sourced from only six basic oils: Palm oil Illipe Sal Shea Kokum gurgi Mango kernel
E. guineensis or E. olifera Shorea stenoptera Shorea robusta Butyrospermum parkii Garcinia indica Mangifera indica
There is also permission within the EU Directive for coconut oil to be used in chocolate on frozen confectionery (i.e., ice cream coatings). In addition to these restrictions on oil type, there are also restrictions on the processes that can be used to modify the oils. Only fractionation and refining are permitted processes. Although there are potentially other processes that could also be used, the only one that is specifically excluded in the EU Directive is “enzymatic modification of the triglyceride structure.” This, therefore, specifically excludes the use of structured triglycerides such as POSt and StOSt, which have been produced by enzymic interesterification, even if their base oils were, for example, palm oil or shea butter. However, the use of triglycerides such as these in confectionery will be considered in more detail in Section 9.7.
Specialty oils and fats in confectionery227
Apart from these restrictions on base oils and permitted processes, there are other restrictions in the EU Directive: l
l
l
they must be nonlauric vegetable oils; this is almost a redundant definition because all of the permitted base oils are nonlauric vegetable oils. However, this restriction goes on to say that they must be rich in symmetrical monounsaturated triglycerides of the type POP, POSt, and StOSt, and they must be miscible in any proportion with cocoa butter and be compatible with its physical properties (melting point and crystallization temperature, melting rate, need for tempering phase).
As well as these restrictions, there are restrictions on the amount of vegetable fat that can be used in chocolate. This is limited to 5%. However, there must be a minimum of 25% cocoa butter (and milk fat, if it is milk chocolate); so, if the total fat content is less than 30% then it is not possible for the full 5% of vegetable fat to be used. In terms of countries other than those in the European Union, where they do permit the use of vegetable fats, the restrictions are mainly on level of use in chocolate and are not generally as complex as those in the EU Directive. In terms of defining what a CBE is and how it is produced, we will first confine this to CBEs that are permitted within the EU and then broaden this out to the rest of the world. It is clear from Figure 9.2 that cocoa butter is essentially composed of three main triglycerides—about 18% POP, about 39% POSt, and about 28% StOSt, giving a total SOS content of about 85%. This will vary from origin to origin but the West African data on which these figures are based is a good average to work on. If we want to make a CBE that conforms to all of the EU Directive then, first, we only have six oils to work on and, second, they should give a finished CBE that it is rich in some or all of these three triglycerides. Palm oil is not considered in detail in this book because it is a commodity and not a specialty fat. Nevertheless, it is an important component of CBEs because it is the main source of POP and so we cannot exclude it from this discussion. In its basic form, palm oil typically contains about 29–30% total SOS. Of this, about 26% is POP and about 3% is POSt, with there being less than 1% StOSt. The rest of palm oil is made up of about 8–9% trisaturated triglycerides (SSS), mainly tripalmitin (PPP), about 7–8% of asymmetrical monounsaturated triglycerides (SSO), mainly PPO, and about 53–54% of triglycerides with greater degrees of unsaturation (Jurriens, 1968). Only the SOS-rich components are of use in CBEs and so palm oil undergoes a double fractionation process to remove both the high-melting SSS fraction (palm top-fraction or palm stearine) and the low-melting more unsaturated triglycerides (palm oleine) leaving a fraction rich in SOS and some SSO (palm mid-fraction). All of the other permitted components are specialty fats and have been discussed in detail in Chapters 4 and 5. Although, as can be seen in the tables in these chapters, there can be considerable variation in the triglyceride compositions of each of these oils they can be summarized as in Table 9.1. Of these base oils, only illipe and kokum have total SOS contents as high as those in cocoa butter. This means that all of the other oils have to be processed to concentrate the SOS triglycerides up to an usable level. It has already been mentioned that palm oil is double fractionated to remove both high- and
228
Table 9.1
base oils
Specialty Oils and Fats in Food and Nutrition
Typical triglyceride compositions of the main CBE
Triglyceride POP POSt StOSt StOA Total SOS
Cocoa buttera
Palmb
Illipeb
Salc
Shead
Kokum gurgie
Mango kernelf
18 39 28
26 3 <1
7 34 45
<1 6 30
2 10 72
3 12 29
85
29
86
2 12 36 8 58
36
84
44
Based on African cocoa butter (from Chaiseri and Dimick, 1989; Talbot, 2009a). Jurriens (1968). c Mean of composition in Table 4.5 of this book. d Talbot (2006). e Mean of composition in Table 4.8 of this book. f Mean of composition in Table 4.11 of this book. a
b
low-melting triglycerides. Similarly, the other oils (shea, sal, and mango kernel) also are fractionated. Usually, only a single fractionation is carried out to remove low-melting triglycerides leaving shea stearine, sal stearine, and mango kernel stearine, respectively. Combining the data on the unfractionated oils (illipe and kokum) with those on the fractionated oils (palm, shea, sal, and mango kernel) gives typical triglyceride compositions of the components normally used in CBEs (Table 9.2). It is clear from Table 9.2 that, now, all of the components have a similar total SOS content to that of cocoa butter, although they do differ considerably in their individual triglyceride compositions. None of them match cocoa butter itself in totality. The nearest is illipe butter but even this is lower in POP and higher in StOSt than is cocoa butter and thus would give a harder product (but one with more CBI-like properties). It is, though, quite an unpredictable crop in terms of availability and so not one that can be particularly relied upon year after year. Nevertheless, it is a very useful component of CBEs when it is available and formed the basis, along with palm mid-fraction, of the first CBEs to be developed (Unilever, 1956). If we are to match the POP content Table 9.2
Typical triglyceride composition of CBE component fats
Triglyceride POP POSt StOSt StOA Total SOS
Cocoa Palm mid- Shea stearineb buttera fractionb
Illipe Sal butterc stearineb
18 39 28
66 12 3
1 7 74
7 34 45
85
81
82
86
<1 10 60 11 81
Based on African cocoa butter (from Chaiseri and Dimick, 1989; Talbot, 2009a). Talbot (2006). Jurriens (1968). d Mean of composition in Table 4.8 of this book. a
b c
Mango Kokum kernel stearineb fatd 2 10 72
1 16 59
84
76
Specialty oils and fats in confectionery229
in cocoa butter then the only component that can do this is palm mid-fraction and, indeed, palm mid-fraction is present in almost all commercial CBEs. The POSt content of cocoa butter can only be matched by the use of illipe and, has as just been pointed out, this is not a crop whose availability can be relied upon. Fortunately, it is possible to match the physical characteristics of cocoa butter, if not its actual triglyceride composition, by using blends of POP and StOSt. StOSt is available from a variety of sources—shea stearine, sal stearine, kokum butter, and mango kernel stearine. Of these, shea stearine is by far the most commonly used component and it is possible to produce a CBE from a blend of palm mid-fraction and shea stearine. Indeed, by varying the ratio of these two components it is possible to produce a spectrum of CBEs ranging from those that work best in low-milk or dark chocolate up to CBIs that improve the performance of cocoa butter. Everything that has been said so far is valid for CBEs irrespective of the country of use (providing, of course, their use is allowed in chocolate in the first place). Outside of the European Union, however, other options are possible, assuming that the fats are available. As well as the six base oils permitted in the EU, it is theoretically possible to use other fats such as pentadesma fat with a stearine rich in StOSt, allanblackia fat, also with a stearine rich in StOSt, aceituno fat with a stearine rich in both POSt and StOSt, mowrah butter with a stearine rich in POP, POSt, and StOSt, and even Chinese vegetable tallow, which is rich in POP. Each of these components are discussed in more detail in Chapter 4. Unfortunately, though, none of them are (yet) widely available commercially. When used in chocolate at, say, the 5% level, the CBE replaces part of the cocoa butter that is added to the recipe. Typical recipes for dark and milk chocolate with and without 5% CBE are shown in Table 9.3. As well as their use in chocolate at a level of, for example, 5%, CBEs can also be used at a much higher level replacing all of the added cocoa butter in chocolate. In this case, it is no longer permissible to call the product “chocolate,” but it is usually labeled as a “chocolate-flavored coating.” In the oils and fats and confectionery industries, though, it is often called a “supercoating” or “supercompound.” Because the triglycerides in the CBE part are the same as those in cocoa butter, a supercoating needs to be tempered in the same way as chocolate and, indeed, in many of its characteristics (melting, snap, flavor release, gloss, etc.) a good quality supercoating is indistinguishable from chocolate. It just cannot be called “chocolate.” Typical dark and milk supercoating recipes are shown in Table 9.4.
9.4 Use of tropical exotic oils (including shea butter) in fillings Fat-based confectionery fillings are not covered by the same well-defined restrictions as is chocolate. This means that, in theory, any edible oil could be used in a filling. In practice they tend to fall into two main groups—those containing nut pastes (which will be considered in Section 9.5) and those based on a vegetable oil with sugar and added flavors, colors, and so on, as appropriate. This is the simplest way of looking at such fillings because, in practice, their compositions vary widely. In terms of the vegetable oil base, though, commodity oils tend to be the most commonly used. Some
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Typical dark and milk chocolate recipes with and without 5% CBE Table 9.3
Cocoa mass Cocoa butter CBE Full cream milk powder Sugar
Dark chocolate (no CBE)
Dark chocolate (5% CBE)
Milk chocolate (no CBE)
Milk chocolate (5% CBE)
40 12
40 7 5
10 22
48
48
10 17 5 34 44
33.2
28.2 5.0
33.2
33.2
100
85.0 15.0
24 44
Fat composition Cocoa butter CBE Milk fat Total fat
27.3 6.5 33.8
22.3 5.0 6.5 33.8
Expressed as % of fat phase Cocoa butter CBE Milk fat Table 9.4
80.8 19.2
66.0 14.8 19.2
Typical dark and milk supercoating recipes
Cocoa mass CBE Full cream milk powder Sugar
Dark supercoating
Milk supercoating
40 12
10 22 24 44
48
Fat composition Cocoa butter CBE Milk fat Total fat
21.2 12.0 33.2
5.3 22.0 6.5 33.8
Expressed as % of fat phase Cocoa butter CBE Milk fat
63.9 36.1
15.7 65.1 19.2
confectionery fillings are based on cocoa butter. This obviously has the benefit of complete compatibility between coating and filling but is also expensive and, unless, the cocoa butter in the filling is softened with a more liquid oil, there are only limited textural differences between coating and filling.
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More common is the use of palm oil or blends of palm fractions as the base of confectionery fillings. These have a number of advantages. Palm oil and its fractions are reasonably priced. The physical properties of both base oil and fractions are widely different meaning that a wide range of melting profiles and, therefore, filling textures can be produced by making different blends. Because palm mid-fraction is rich in POP, fillings containing palm mid-fraction have a good compatibility with chocolate. However, first, palm oil as a commodity is outside the scope of this book, and, second, some manufacturers are starting to move away from the use of palm-derived fats for reasons of either high levels of saturated fat or concerns about sustainability. Both of these concerns can be countered in the sense that any alternative with a similar melting profile is also likely to include some saturated fat, and that palm oil from sustainable sources is readily available. Nevertheless, these concerns are still there and often it is shea butter that comes in as an alternative. Figure 9.4 compares the melting profiles of palm oil and shea butter. Both oils have approximately the same level of saturated fat (about 50%), although this is predominantly palmitic acid in palm oil and stearic acid in shea butter. Because the saturates in shea butter are mainly stearic acid and because this is higher melting than palmitic acid the solid fat content of shea butter at any given temperature on its melting profile is higher than that of palm oil. For example, at 20 °C the solid fat content of shea butter is approximately twice that of palm oil. This means that in order to match the melting profile of a palm-based filling fat with one using shea butter it will be necessary to soften the shea butter. The obvious way to do this is to add some liquid vegetable oil, for example, rapeseed oil or even shea oleine. This not only brings the melting profile into line with that of the original filling but also reduces the saturates level in shea butter. Although shea butter is perhaps the most obvious oil to use in such fillings the basic premise can be used with any of the other exotic tropical oils (illipe, sal, kokum, mango kernel) to achieve an alternative filling fat composition. In all cases, compatibility of the filling fat with cocoa butter in a chocolate coating is maintained. 70 60
% Solid fat
50 40 30 20 10 0 0
10
20
30
40
Temp. ( C) Shea butter
Palm oil
Figure 9.4 Comparative melting profiles of palm oil and shea butter.
50
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As well as using fats in fillings that have a good compatibility with cocoa butter it is also common to find confectionery fillings that are based on lauric fats, which have limited or no compatibility with chocolate. Often these are based on palm kernel oil, particularly biscuit cream fillings, which are outside the scope of this book, but also fillings based on coconut oil are used. Both coconut oil itself and fully hydrogenated (and, hence, trans-free) coconut oil are used to give coolness to fillings. This is because of their very steep melting profiles, which go from fairly high levels of solid fat down to completely molten in a short temperature range just above ambient temperatures. This very rapid meltdown extracts latent heat from the mouth, which results in a cooling of the mouth and thus a cool sensation. This coolness can be enhanced by using dextrose in the filling and even by adding some peppermint oil to the filling. One of the main problems with using coconut oil, fully hydrogenated coconut oil, and also palm kernel oil in this way is that the oils are incompatible with cocoa butter and so any migration of filling fat into the chocolate will result in a softening of the chocolate and the possibility of fat bloom formation. The effects of combining cocoa butter and palm kernel oil, for example, are shown in Figure 9.5. The effects are very similar for interactions between cocoa butter and coconut oil. Even relatively low levels of oil migration from filling to coating will result in considerable softening of the chocolate. For example, 20% migration of palm kernel oil into the chocolate reduces the solid fat content at 20 °C from 76% to 55%; 40% migration will reduce the same solid fat content from 76% to 36% (Talbot, 2008). Migration to this extent will soften the chocolate
80 70
% Solid fat
60 50 40 30 20 10 0
0
20
40
60
80
% Palm kernel oil N20
N25
N30
Figure 9.5 Interactions between cocoa butter and palm kernel oil. Based on Talbot (2008).
100
Specialty oils and fats in confectionery233
so much as to make it very difficult to handle. One way in which the confectionery industry has overcome this is to dispense with the chocolate coating altogether and to sell coconut oil-based fillings as such, often in foil cups known as “ice cups.”
9.5 Use of tree nut oils Nuts as a whole and nut butters as filling pastes form an important part of both confectionery inclusions and centers. Perhaps the most common nut used in this way is the peanut, which, of course, grows underground and is not, therefore, a tree nut in the sense that hazelnuts, brazil nuts, walnuts, and almonds are. Hazelnuts are often used as inclusions both in the form of the whole nut and as chopped pieces. Brazil nuts are generally used as the total center; that is, the whole nut is coated in chocolate and marketed simply as the nut with a chocolate coating. Almonds can be used both whole (as inclusions in solid molded bars of chocolate) or chopped (as inclusions in filling). One of the most common uses of walnuts in confectionery is as a component in “walnut whips” in which a pyramid of chocolate containing a mallow filling is topped with a walnut. As far as nut oils are concerned, the main issue with these products is that there is the potential for these to migrate out of the nut into the chocolate, thus causing softening and, potentially, fat bloom. This is more of a problem with chopped nuts than with whole nuts because of the greater surface area. The whole problem of nut oil migration is greatly enhanced, though, when nut pastes are used as part of a filling composition because in paste form the nut oils are much more readily available to migrate. The use of nut pastes in confectionery fillings originated with the praline. The name praline is often thought to have originated with the seventeenth century Duke of Plessis-Praslin whose cook is supposed to have first coated whole almonds in caramelized sugar (Food Timeline, 2014). Over time this changed from coated whole nuts to a powdered version of the caramelized sugar-coated nuts. As well as this change, hazelnuts began to be commonly used as well as almonds. As the development of these fillings progressed it also became common to simply use a nut paste, often hazelnut paste, as a component in a confectionery filling, still usually known as a praline. A typical hazelnut paste-based filling recipe is (Talbot, 2014): Dark chocolate 15.0% Hazelnut paste 15.0% Full cream milk powder 10.0% Filling fat 20.0% Sugar 34.6% Chopped hazelnuts 5.0% Lecithin 0.4%
The filling fat is important because it helps to give structure to the whole filling, making it easier to handle as well as reducing the overall content of liquid nut oils that are available to migrate into the chocolate. Even small amounts of nut oil migrating from the filling into the chocolate can have a major effect on the shelf life and stability of the chocolate. Smith et al. (2008) found that even as little as 1% nut oil migrating
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into chocolate can accelerate the rate of polymorphic change from form βV to form βVI in chocolate, eventually resulting in fat bloom formation. Greater degrees of migration will both accelerate that rate of change and of bloom formation and will also result in a much softer chocolate. Using a filling fat that gives structure and reduces the overall level of hazelnut paste (oil) in the filling will help to reduce the rate and extent of migration and maintain a harder chocolate. The oils and fats company IOI Loders Croklaan (2014), for example, suggest a recipe using their filling fat Creamelt™ 501 to improve the structure of a hazelnut paste filling: Creamelt™ 501 40.0% Cocoa powder 5.0% Hazelnut paste 15.0% Full cream milk powder 5.0% Sugar 34.6% Lecithin 0.4%
To minimize the polymorphic transformation in the cocoa butter in the chocolate shell that can result in bloom as a result of nut oil migration, it is necessary to include an antibloom fat in the filling recipe (Smith et al., 2008). IOI Loders Croklaan (2014) also suggests such a formulation using Prestine™ 34F, an antibloom filling fat: Prestine™ 34F 28.0% Hazelnut paste 20.0% Full cream milk powder 3.0% Skimmed milk powder 4.0% Sugar 44.6% Lecithin 0.4%
9.6 Use of essential oils The use of triglyceride-based botanical oils in confectionery is quite limited but the use of essential oils is more common. These are oils that will give some form of flavor either to chocolate or to a filling, and the use of mint oil, orange oil, and lemon oil is quite common. In addition to these, rose oil is also used in Turkish Delight recipes. In scientific terms, perhaps one of the most interesting series of studies using oils such as these in chocolate is the one concerned with the effect of limonene on the properties of chocolate. One of the main problems in reducing the fat content of chocolate is that removing fat increases the viscosity, making the chocolate more difficult to handle. Do et al. (2008) found that adding limonene to chocolate considerably reduced its viscosity, thus opening the door to the possibility of more easily producing a low-fat chocolate. The disadvantage was that, as well as reducing the viscosity of the chocolate, it also reduced its hardness. Ray et al. (2012) took this one stage farther and found that the addition of limonene to chocolate enhanced the production of lower polymorphic forms (α and β′IV) on cooling but then accelerated their transformation into the more stable βV form.
Specialty oils and fats in confectionery235
9.7 Use of structured triglycerides The background to and the production of structured triglycerides is considered in detail in Chapter 8. As an introduction to this section all that needs to be said is that structured triglycerides are triglycerides that are produced, often by enzymic interesterification, that are either not found in natural oils and fats or are limited by availability. As far as confectionery uses are concerned, there are a number of different types of structured triglycerides that have been used, each with different applications. Possibly the main group of these triglycerides are the SOS types; that is, triglycerides similar to those found in cocoa butter. Mention has already been made in this chapter of the difficulty of sourcing oils rich in POSt to match the POSt content of cocoa butter in a CBE. Illipe and aceituno stearine are the only alternative sources and these are either variable or limited in availability. However, using a triglyceride rich in 2-position oleic acid (for example, high oleic sunflower oil or palm oleine) and enzymically interesterifying this with a mix of palmitic and stearic acids will give an end product that contains significant levels of POSt (as well as POP and StOSt). It will need to be cleaned up by a combination of fatty acid removal and fractionation but the end product is either a CBE in its own right or a very useful component of a CBE. In a similar way, an end product rich in StOSt can also be produced. This process was developed by Unilever, largely as a means of supplementing the availability of POSt and StOSt at times of restricted availability of illipe and shea (Macrae, 1983). Since then the process has broadened widely in both the types and applications of triglycerides produced in this way and also in the use of these cocoa butter-like triglycerides in confectionery. The point made in Section 9.3 that the use of this process to produce the vegetable fats permitted in EU chocolate is prohibited needs to be reiterated. However, this exclusion only applies to the EU and enzymically produced POSt and StOSt are used in CBEs in other countries where these are allowed. A specific type of SOS that is produced in this way is BOB (1,3-dibehenyl, 2-oleoylglycerol). This was developed by the Fuji Oil Company in Japan and incorporates two behenic acid (C22:0) groups in the 1- and 3-positions of the triglyceride as well as the more usual oleic acid group in the 2-position. Because it is still a SOS triglyceride it has excellent compatibility with cocoa butter but, because of the two high-melting behenic acid groups, it has a much higher melting point (53 °C) than cocoa butter. Its main uses are as a seed to temper chocolate and as an antibloom fat. If a small amount of BOB is incorporated into chocolate and that chocolate then melts because, for example, it has been stored at a very high ambient temperature, then, unless the storage temperature is excessively high, the BOB will remain in the chocolate in a solid state. When the chocolate cools back down again the BOB will reseed the chocolate and, therefore, prevent the bloom formation that would otherwise occur (Koyano et al., 1990). The behenic acid is obtained from the complete hydrogenation of high-erucic acid rapeseed oil. This is the original type of rapeseed oil that used to be grown widely many years ago until it was found that the erucic acid (C22:1) in the oil was implicated in raising the risk of heart disease. As a result of plant breeding work, a new variety of rapeseed oil (also known as canola oil) was produced that,
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instead of being rich in erucic acid, is rich in oleic acid. This is the variety that is now grown widely across North America and Europe, almost to the exclusion of the original high-erucic variety. However, there is still a small amount of the original crop grown for very specific uses such as this in which the erucic acid is converted into behenic acid by hydrogenation. Another use of behenic acid in a structured triglyceride is in the production of Caprenin™. Caprenin™ was developed by the Proctor and Gamble Company as a low-calorie CBR. It is composed of caprylic (C8:0), capric (C10:0), and behenic (C22:0) acids. Capric and caprylic acids are produced from coconut oil and together comprise a group of structured triglycerides known as medium-chain triglyceride oils. These have very specific uses in both sports and postoperative nutrition because they deliver energy to the body differently than longer-chain triglycerides and also have a slightly lower calorie content. Behenic acid, on the other hand, is so high-melting that it effectively passes through the body unabsorbed. The result of combining these fatty acids together in a single triglyceride is one that not only melts close to the melting temperature of cocoa butter but also has a lower calorific content (said to be about 5 kcal/g). Another structured triglyceride that is used in confectionery and that has a lower calorific content than conventional triglycerides is Salatrim®, now known as Benefat®. Salatrim® is an acronym for Short And Long-chain Acyl TRIglyceride Molecules. The short-chain acids are acetic (C2:0), propionic (C3:0), or butyric (C4:0) acids while the long-chain acid is usually stearic acid (C18:0) obtained by complete hydrogenation of liquid oils such as soyabean, rapeseed, sunflower, or cottonseed. These are interesterified in triglyceride form and triglycerides with either three short-chain or three long-chain acids are removed. Benefat® is produced by Danisco and is available in a number of forms, one of which is suitable as a partial CBS. It can be used at levels of up to 10% in place of cocoa butter in chocolate-like products, but because it does not give a “snap” to the product cannot be used in molded bars (Danisco, 2014). It does, though, find application in chocolate chips for use in baking. It has a calorific content of 6 kcal/g.
9.8 Future trends This chapter has been divided into sections intended to reflect some of those in the first part of this book. In terms of future trends, we can try to predict these using the same basic section headings.
9.8.1 Tropical exotic oils As far as EU chocolate is concerned, it took a long time for all the parties concerned to come to an agreement that resulted in the Chocolate Directive of 2000 (European Union, 2000). It is likely, therefore, to take an equally long time to change any of the restrictions placed on the use of vegetable oils in chocolate in that directive. This
Specialty oils and fats in confectionery237
means that the six base oils defined in the legislation are likely to remain there for some years to come, thus preventing the use of oils with similar triglyceride compositions that are not on the permitted list from being used. Having said that, the main oils in use are still palm oil and shea butter with lesser amounts of sal oil and illipe butter being included. Scope exists, therefore, for greater production and use of the other oils, kokum, and mango kernel. Although palm oil will remain as the main vegetable oil used globally for many years to come, there will still be some pressure on it in more niche markets in terms of its level of saturation and particularly in terms of environmental concerns. This is likely, then, to open the door to a greater usage of shea butter and its fractions, especially if these can be supplied in an organic, sustainable, and fairly traded form. Other tropical exotic oils may also start to come more into the mainstream. Unilever’s interest in allanblackia oil, while not being specifically confectionery related, may help to bring it into use in some areas of the world as a confectionery fat. Similarly, there is interest in Sri Lanka in converting some of the land used to grow tea into areas for pentadesma cultivation. This would then bring another potential CBE component onto the market.
9.8.2 Tree nut oils As manufacturers look for new product ideas, new tree nuts may well come into use in confectionery products. So, as well as the mainstream hazelnut, almond, and brazil nut, we are already seeing, for example, chocolate-coated macadamia nuts. Cashew nuts are not often seen in confectionery products but are a popular “snacking” nut— perhaps there is scope for a greater use of these in confectionery.
9.8.3 Botanical oils The use of triglyceride-based botanical oils in confectionery is quite limited so, as the use of these increases in other areas, there may be some applications in chocolate confectionery. Examples could be a focused use of, for example, evening primrose oil in confectionery targeted at women, or the incorporation of omega-3-rich oils (e.g., flaxseed) or oils such as blackcurrant seed oil with its interesting mix of omega-3, omega-6, and stearidonic acids.
9.8.4 Structured triglycerides The whole area of structured triglycerides is one that is likely to continue to develop and new base oils are likely to be used, even to produce triglycerides such as StOSt that can already be made using this technology. As an example, a CBR has been developed from the enzymatic interesterification of hydrogenated and fractionated tea seed oil (Zarringhalami et al., 2010). Similarly, a cocoa butter analogue has been produced from camel hump fat (Shekarchizadeh et al., 2009). It is also likely that new structured triglycerides will be introduced into confectionery that are either lower calorie or that are suitable for sports and other types of nutrition.
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References Beckett, S.T. (Ed.), 2009. Industrial Chocolate Manufacture and Use, fourth ed. WileyBlackwell, Oxford. Chaiseri, S., Dimick, P.S., 1989. Lipid and hardness characteristics of cocoa butter from different geographical areas. J. Am. Oil Chem. Soc. 66, 1771–1776. Danisco, 2014. Benefat® reduced calorie triglycerides. http://www.aditiva-concepts.ch/ download/BENEFAT.pdf (accessed 15.05.14). Do, T.-A.L., Vieira, J., Hargreaves, J.M., Wolf, B., Mitchell, J.R., 2008. Impact of limonene on the physical properties of reduced fat chocolate. J. Am. Oil Chem. Soc. 85, 911–920. European Union, 2000. Directive 2000/36/EC of the European Parliament and of the Council of 23 June 2000 Relating to Cocoa and Chocolate Products Intended for Human Consumption. Food Timeline, 2014. FAQs candy. http://www.foodtimeline.org/foodcandy.html#praline (accessed 14.05.14). IOI Loders Croklaan, 2014. Filling fats. pp. 7, 15. http://europe.croklaan.com/images/static_ pages/Filling_Fats_English.pdf (accessed 14.05.14). Jurriens, G., 1968. Analysis of triglycerides. In: Boekenoogen, H.A. (Ed.), Analysis and Characterisation of Oils and Fats and Fat Products, vol. 2. Interscience Publishers, London. p. 279. Koyano, T., Hachiya, I., Sato, K., 1990. Fat polymorphism and crystal seeding effects on fat bloom stability of dark chocolate. Food Struct. 9, 231–240. Lipp, M., Anklam, E., 1998. Review of cocoa butter and alternative fats for use in chocolate— Part A. Compositional data. Food Chem. 62, 73–97. Macrae, A.R., 1983. Lipase-catalyzed interesterification of oils and fats. J. Am. Oil Chem. Soc. 60, 291–294. Ray, J., MacNaughton, W., Chong, P.S., Vieira, J., Wolf, B., 2012. The effect of limonene on the crystallisation of cocoa butter. J. Am. Oil Chem. Soc. 89, 437–445. Richter, K., 2009. Tempering process technology. In: Talbot, G. (Ed.), Science and Technology of Enrobed and Filled Chocolate, Confectionery and Bakery Products. Woodhead Publishing, Cambridge. Shekarchizadeh, H., Kadivar, M., Ghaziaskar, H.S., Rezayat, M., 2009. Optimization of enzymatic synthesis of cocoa butter analog from camel hump fat in supercritical carbon dioxide by response surface method (RSM). J. Supercrit. Fluids 49, 209–215. Smith, K.W., 2009. Ingredient preparation: the science of tempering. In: Talbot, G. (Ed.), Science and Technology of Enrobed and Filled Chocolate, Confectionery and Bakery Products. Woodhead Publishing, Cambridge. Smith, K.W., Zand, I.T., Talbot, G., 2008. Effect of anti-bloom fat migration from a nut oil filling on the polymorphic transformation of cocoa butter. J. Agric. Food Chem. 56, 1602–1605. Talbot, G., 2006. Application of Fats in Confectionery. Kennedy’s Publications, London. Talbot, G., 2008. Interactions between coating fats and filling fats. In: Lecture Given at ZDS Chocolate Technology Conference, Cologne. Talbot, G., 2009a. Fats for confectionery coatings and fillings. In: Talbot, G. (Ed.), Science and Technology of Enrobed and Filled Chocolate, Confectionery and Bakery Products. Woodhead Publishing, Cambridge. Talbot, G., 2009b. Compound coatings. In: Talbot, G. (Ed.), Science and Technology of Enrobed and Filled Chocolate, Confectionery and Bakery Products. Woodhead Publishing, Cambridge. Talbot, G., 2014. Fats for chocolate and sugar confectionery. In: Rajah, K.K. (Ed.), Fats in Food Technology, second ed.
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Unilever, 1956. Improvements in or relating to cocoa butter substitutes. GB Patent 827172. Wille, R.L., Lutton, E.S., 1966. Polymorphism of cocoa butter. J. Am. Oil Chem. Soc. 43, 491–496. Zarringhalami, S., Sahari, M.A., Barzegar, M., Hamidi-Esfehani, Z., 2010. Enzymatically modified tea seed oil as cocoa butter replacer in dark chocolate. Int. J. Food Sci. Technol. 45, 540–545.
9
G. Talbot The Fat Consultant, Bedford, UK
Abbreviations A Li Ln O P S St U
arachidic acid (C20:0) linoleic acid (C18:2) linolenic acid (C18:3) oleic acid (C18:1) palmitic acid (C16:0) total saturates stearic acid (C18:0) total unsaturates
9.1 Introduction The term confectionery can cover a wide range of food products, some of which are being covered in other chapters in this book. For example, ice cream can come under the category of “frozen confectionery” and this is discussed in Chapter 11. Many bakery products, particularly sweet bakery products such as biscuits, cakes, and patisserie, are also sometimes referred to as confectionery. The types of confectionery that will be considered in this chapter are ambient-stable, often chocolate-based confectionery products. Clearly, not all of the types of oils considered in the first part of this book are used in these types of confectionery products. There is little, if any, use of olive oil, for example, in chocolate confectionery products; oils such as flaxseed oil or hemp oil have minimal applications in these products, as do algal oils. On the other hand, tropical exotic oils, including shea butter and its derivatives, have a widespread use in chocolate confectionery; tree nuts are often used as inclusions in chocolate confectionery and tree nut butters are the basis of many truffle centers. Although not considered specifically in the first part of the book, essential oils such as mint oil, orange, and lemon oils have a flavoring role in confectionery. Finally, structured triglycerides have been and still are used in a number of very specific applications in confectionery. It is the use of these types of oils that will be the main focus of this chapter.
Specialty Oils and Fats in Food and Nutrition. http://dx.doi.org/10.1016/B978-1-78242-376-8.00009-0 © 2015 Elsevier Ltd. All rights reserved.
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9.2 Cocoa butter In terms of the fats used, the basis of almost all chocolate confectionery is cocoa butter. Cocoa butter itself has not been a focus in this book because it is considered to be more of a commodity fat than a specialty fat. This, though, is a consideration based mainly on trade and availability of cocoa butter (although there are some years when the availability is more limited and the price increases dramatically, potentially pushing it into the specialty area). If, though, we base the definition of specialty or commodity on chemical composition, physical characteristics, and application, then cocoa butter does fall into the category of being a specialty fat. Because much of the use of tropical exotic oils and some structured triglycerides in confectionery are based on matching physical characteristics to those of cocoa butter, cocoa butter itself is a good place to start. Cocoa butter is extracted from the beans (seeds) of the Theobroma cacao tree (Beckett, 2009). The tree produces pods that contain these beans. Cocoa is grown in a region between 10° and 20° north and south of the equator and is, therefore, found in three main geographical regions: Central and South America, West Africa, and Southeast Asia (largely, Malaysia and Indonesia). Cocoa butter has a very specific fatty acid and triglyceride composition and it is this that gives it its very specific physical characteristics that make it so useful as a base for confectionery. Add to that the distinctive flavor of both cocoa butter and cocoa powder and it becomes very clear why chocolate is a product liked the world over. Cocoa butter is mainly composed of three fatty acids—palmitic (C16:0), stearic (C18:0), and oleic (C18:1)—together with low levels of linoleic acid (C18:2) and arachidic acid (C20:0). The relative levels of these fatty acids differ from origin to origin (Figure 9.1) with South American (Brazilian) cocoa butter containing higher levels of unsaturated fatty acids than cocoa butters from other growing regions, and Asian (Malaysian) cocoa butter containing less palmitic acid and more stearic acid than cocoa butter from West Africa (Ivory Coast). These fatty acids translate then into different triglyceride compositions with South American cocoa butters containing higher levels of unsaturated triglycerides such as SLiS and SOO, and Asian cocoa butters containing higher levels of POSt and StOSt (Figure 9.2). These differences in fatty acid and triglyceride composition result in significant differences in the solid fat contents and melting profiles of cocoa butters from different origins (Figure 9.3). The very specific triglyceride composition of cocoa butter, particularly its high level of total SOS triglycerides, means that cocoa butter is a highly polymorphic fat. In other words, it is a fat that can crystallize in a number of different polymorphic, or crystal, forms. In general, fats can crystallize in three basic polymorphic forms— alpha (α), beta-prime (β′), and beta (β)—although forms of lower stability than these three—gamma (γ) and delta (δ)—have also been observed. The polymorphism of fats, with particular reference to cocoa butter, is described in more detail by Talbot (2009a, pp. 57–61). Essentially, cocoa butter can crystallize in up to six different polymorphic forms; despite extensive research, the exact number, five or six, is still the subject of much debate. These different polymorphic forms have different stabilities and
Specialty oils and fats in confectionery223 40 35 30 25 20 15 10 5 0 C16:0
C18:0 Brazil
C18:1
Ivory Coast
C18:2
Malaysia
Figure 9.1 Fatty acid compositions of cocoa butter of different origins. Taken from Lipp and Anklam (1998) and Talbot (2009a). 45 40 35 30 25 20 15 10 5 0 POP
POSt S. America
StOSt Africa
SLiS + SOO
Asia
Figure 9.2 Triglyceride compositions of cocoa butter of different origins. Taken from Chaiseri and Dimick (1989) and Talbot (2009a).
d ifferent melting points. The most stable are two slightly different β forms. Early work by Wille and Lutton (1966) on which much of the nomenclature of these forms is based identified six forms called Forms I–VI, with Form VI being the most stable and the highest melting. Because both of the most stable forms are β forms they are now often referred to as βV and βVI.
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% Solid fat (by NMR)
80 70 60 50 40 30 20 10 0 15
20
Malaysian
25 30 Temperature ( C) West African
35
40
Brazilian
Based on information from Loders Croklaan, undated
Figure 9.3 Melting profiles of cocoa butters of different origins.
When it is being processed in chocolate, it is necessary to ensure that cocoa butter crystallizes in one of these stable β forms and in order to ensure that this happens, chocolate goes through a process of tempering. The science of tempering is described in detail by Smith (2009) and the process itself by Richter (2009). In summary, though, chocolate is cooled from a molten state at about 45–50 °C to a temperature of about 24–28 °C (so that some crystallization of cocoa butter can be initiated in a reasonable time frame) and then reheated to a temperature of about 27–33 °C. The actual temperatures used depend on the composition of the chocolate (the origin of the cocoa butter, the amount of milk fat used in a milk chocolate, the nature of any vegetable fat added to the chocolate). When the chocolate is cooled to 24–28 °C, both stable βV crystals and unstable β′ (Form IV) crystals are produced. The unstable crystals are not wanted (and if they are retained will adversely affect the quality of the end chocolate) and so the temperature of the chocolate is raised to a point above the melting point of the β′ crystals but still below the melting point of βV crystals. This then leaves only βV crystals. Even in a well-tempered chocolate the level of βV crystals present is very low (typically about 1%) but it is high enough to then “seed” the crystallization of the remaining cocoa butter in this same crystal form when the chocolate is cooled more rapidly in a cooling tunnel. The βV crystals present in well-tempered chocolate are not in the most stable polymorphic form—this is the βVI form. It is, though, not possible (with current technology, at least) for cocoa butter in chocolate to crystallize directly in the βVI crystal form. Indeed, once a chocolate has been well tempered and crystallized into the βV form it is beneficial to try to keep the cocoa butter in that form because transformation on storage into the βVI form is often accompanied by the formation of a whitish film of fat bloom on the surface of the chocolate.
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Because of the high and fluctuating price of cocoa butter, fat processors have developed various types of cocoa butter alternative. These have mainly been developed as cheaper alternatives to chocolate and so one of the main requirements has been that they should melt in a similar way to cocoa butter so that any coatings based on the alternative match chocolate in that regard. This can be achieved from a variety of fats but some not only match the melting profile of cocoa butter they also are a good match to the triglyceride composition of cocoa butter. These require the use of tropical exotic oils for their production.
9.3 Use of tropical exotic oils (including derivatives of shea butter) in coatings There are three basic types of cocoa butter alternative: ●
●
●
cocoa butter equivalents (CBEs), cocoa butter replacers (CBRs), and cocoa butter substitutes (CBSs).
CBSs are based on lauric fats, that is, fats that are rich in lauric acid (C12:0). In commercial terms there are only two lauric fats of any significance for use in this type of application: palm kernel oil and coconut oil. Palm kernel oil is derived, along with palm oil, from the oil palm, Elaeis guineensis and Elaeis olifera. In the context of which are specialty and which are commodity oils, both palm oil and palm kernel oil are considered to be commodities and are therefore not being considered in any detail in this book. Coconut oil is on the cusp between commodity and specialty but has been included in this book and its characteristics are described in detail in Section 4.11. In their basic, unprocessed forms both palm kernel oil and coconut oil are too soft for use as an alternative to cocoa butter in ambient confectionery coatings. They can, though, both be used in ice cream coatings (see Chapter 11). Palm kernel oil, when fractionated, gives a stearine that has solid fat contents that are suitable for use in a CBS. Despite similarities in their basic oil forms, coconut oil, when fractionated, is still too soft for use in a confectionery coating on ambient confectionery. For this reason, coconut oil will not be considered in this application, but will be discussed later in this chapter as a base for confectionery fillings. CBRs have traditionally been based on partially hydrogenated and fractionated combinations of palm oil, soyabean oil, cottonseed oil, and rapeseed oil. Since the decline in the use of hydrogenation as an oil modification process, CBRs have largely been produced from fractions of palm oil. Other than in the area of modified traits (see Chapter 7), none of these oils can be considered to be specialty oils and so the area of CBRs will also not be considered further in this chapter. Readers who want to know more about both CBS and CBR cocoa butter alternatives are directed to Talbot (2009b). This then leaves only CBEs, and it is in this type of product that tropical exotic oils really come into widespread use. In this context, not only will many of the tropical exotic oils described in Chapter 4 be considered but also oils derived from shea butter
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(Chapter 5) as perhaps the most important specialty component in CBEs. CBEs are vegetable fats that not only melt in the same way as does cocoa butter but, unlike CBSs and CBRs, they also are composed of the same types of symmetrical monounsaturated triglycerides (SOS) as are found in cocoa butter itself. Hence, they are equivalent to cocoa butter in all senses—composition, melting, crystallization, polymorphism, need for tempering, and so on. Although they are usually referred to as CBEs, these fats have a much broader spectrum than simply being equivalent to cocoa butter. Some do match the properties of cocoa butter extremely well, but others are softer than cocoa butter and have been used, not so much to replace some of the cocoa butter in chocolate but some of the milk fat as well. This has been done particularly at times when cocoa butter has been relatively low in price and milk fat higher in price. Other vegetable fats are harder and higher melting than cocoa butter and are often referred to as cocoa butter improvers (CBIs). These are used for a variety of reasons: they produce a more heat-resistant chocolate for warmer countries; they produce a more bloom-resistant chocolate; and they are more resistant to the effects of oil migration from a soft filling. Whatever label may be put on them—CBE, milk fat replacers (MFR), CBI, etc.—they are all vegetable fats and so their use in chocolate is subject to national legislation on the use of vegetable fats in chocolate. Perhaps the most detailed legislation on the use of vegetable fats in chocolate is that of the European Union (2000). Many other countries also have legislation to allow the use of vegetable fats in chocolate but, unlike the European Union (EU) legislation, most simply limit the amount of vegetable fat that can be used without putting any limitations on the types of fat that can be used. Other countries, such as the United States, do not allow vegetable fats to be used in products labeled “chocolate.” The European Union, though, put restrictions on the types of vegetable fat that can be used and the ways in which that fat can be processed. In terms of its type, the fats used can be sourced from only six basic oils: Palm oil Illipe Sal Shea Kokum gurgi Mango kernel
E. guineensis or E. olifera Shorea stenoptera Shorea robusta Butyrospermum parkii Garcinia indica Mangifera indica
There is also permission within the EU Directive for coconut oil to be used in chocolate on frozen confectionery (i.e., ice cream coatings). In addition to these restrictions on oil type, there are also restrictions on the processes that can be used to modify the oils. Only fractionation and refining are permitted processes. Although there are potentially other processes that could also be used, the only one that is specifically excluded in the EU Directive is “enzymatic modification of the triglyceride structure.” This, therefore, specifically excludes the use of structured triglycerides such as POSt and StOSt, which have been produced by enzymic interesterification, even if their base oils were, for example, palm oil or shea butter. However, the use of triglycerides such as these in confectionery will be considered in more detail in Section 9.7.
Specialty oils and fats in confectionery227
Apart from these restrictions on base oils and permitted processes, there are other restrictions in the EU Directive: l
l
l
they must be nonlauric vegetable oils; this is almost a redundant definition because all of the permitted base oils are nonlauric vegetable oils. However, this restriction goes on to say that they must be rich in symmetrical monounsaturated triglycerides of the type POP, POSt, and StOSt, and they must be miscible in any proportion with cocoa butter and be compatible with its physical properties (melting point and crystallization temperature, melting rate, need for tempering phase).
As well as these restrictions, there are restrictions on the amount of vegetable fat that can be used in chocolate. This is limited to 5%. However, there must be a minimum of 25% cocoa butter (and milk fat, if it is milk chocolate); so, if the total fat content is less than 30% then it is not possible for the full 5% of vegetable fat to be used. In terms of countries other than those in the European Union, where they do permit the use of vegetable fats, the restrictions are mainly on level of use in chocolate and are not generally as complex as those in the EU Directive. In terms of defining what a CBE is and how it is produced, we will first confine this to CBEs that are permitted within the EU and then broaden this out to the rest of the world. It is clear from Figure 9.2 that cocoa butter is essentially composed of three main triglycerides—about 18% POP, about 39% POSt, and about 28% StOSt, giving a total SOS content of about 85%. This will vary from origin to origin but the West African data on which these figures are based is a good average to work on. If we want to make a CBE that conforms to all of the EU Directive then, first, we only have six oils to work on and, second, they should give a finished CBE that it is rich in some or all of these three triglycerides. Palm oil is not considered in detail in this book because it is a commodity and not a specialty fat. Nevertheless, it is an important component of CBEs because it is the main source of POP and so we cannot exclude it from this discussion. In its basic form, palm oil typically contains about 29–30% total SOS. Of this, about 26% is POP and about 3% is POSt, with there being less than 1% StOSt. The rest of palm oil is made up of about 8–9% trisaturated triglycerides (SSS), mainly tripalmitin (PPP), about 7–8% of asymmetrical monounsaturated triglycerides (SSO), mainly PPO, and about 53–54% of triglycerides with greater degrees of unsaturation (Jurriens, 1968). Only the SOS-rich components are of use in CBEs and so palm oil undergoes a double fractionation process to remove both the high-melting SSS fraction (palm top-fraction or palm stearine) and the low-melting more unsaturated triglycerides (palm oleine) leaving a fraction rich in SOS and some SSO (palm mid-fraction). All of the other permitted components are specialty fats and have been discussed in detail in Chapters 4 and 5. Although, as can be seen in the tables in these chapters, there can be considerable variation in the triglyceride compositions of each of these oils they can be summarized as in Table 9.1. Of these base oils, only illipe and kokum have total SOS contents as high as those in cocoa butter. This means that all of the other oils have to be processed to concentrate the SOS triglycerides up to an usable level. It has already been mentioned that palm oil is double fractionated to remove both high- and
228
Table 9.1
base oils
Specialty Oils and Fats in Food and Nutrition
Typical triglyceride compositions of the main CBE
Triglyceride POP POSt StOSt StOA Total SOS
Cocoa buttera
Palmb
Illipeb
Salc
Shead
Kokum gurgie
Mango kernelf
18 39 28
26 3 <1
7 34 45
<1 6 30
2 10 72
3 12 29
85
29
86
2 12 36 8 58
36
84
44
Based on African cocoa butter (from Chaiseri and Dimick, 1989; Talbot, 2009a). Jurriens (1968). c Mean of composition in Table 4.5 of this book. d Talbot (2006). e Mean of composition in Table 4.8 of this book. f Mean of composition in Table 4.11 of this book. a
b
low-melting triglycerides. Similarly, the other oils (shea, sal, and mango kernel) also are fractionated. Usually, only a single fractionation is carried out to remove low-melting triglycerides leaving shea stearine, sal stearine, and mango kernel stearine, respectively. Combining the data on the unfractionated oils (illipe and kokum) with those on the fractionated oils (palm, shea, sal, and mango kernel) gives typical triglyceride compositions of the components normally used in CBEs (Table 9.2). It is clear from Table 9.2 that, now, all of the components have a similar total SOS content to that of cocoa butter, although they do differ considerably in their individual triglyceride compositions. None of them match cocoa butter itself in totality. The nearest is illipe butter but even this is lower in POP and higher in StOSt than is cocoa butter and thus would give a harder product (but one with more CBI-like properties). It is, though, quite an unpredictable crop in terms of availability and so not one that can be particularly relied upon year after year. Nevertheless, it is a very useful component of CBEs when it is available and formed the basis, along with palm mid-fraction, of the first CBEs to be developed (Unilever, 1956). If we are to match the POP content Table 9.2
Typical triglyceride composition of CBE component fats
Triglyceride POP POSt StOSt StOA Total SOS
Cocoa Palm mid- Shea stearineb buttera fractionb
Illipe Sal butterc stearineb
18 39 28
66 12 3
1 7 74
7 34 45
85
81
82
86
<1 10 60 11 81
Based on African cocoa butter (from Chaiseri and Dimick, 1989; Talbot, 2009a). Talbot (2006). Jurriens (1968). d Mean of composition in Table 4.8 of this book. a
b c
Mango Kokum kernel stearineb fatd 2 10 72
1 16 59
84
76
Specialty oils and fats in confectionery229
in cocoa butter then the only component that can do this is palm mid-fraction and, indeed, palm mid-fraction is present in almost all commercial CBEs. The POSt content of cocoa butter can only be matched by the use of illipe and, has as just been pointed out, this is not a crop whose availability can be relied upon. Fortunately, it is possible to match the physical characteristics of cocoa butter, if not its actual triglyceride composition, by using blends of POP and StOSt. StOSt is available from a variety of sources—shea stearine, sal stearine, kokum butter, and mango kernel stearine. Of these, shea stearine is by far the most commonly used component and it is possible to produce a CBE from a blend of palm mid-fraction and shea stearine. Indeed, by varying the ratio of these two components it is possible to produce a spectrum of CBEs ranging from those that work best in low-milk or dark chocolate up to CBIs that improve the performance of cocoa butter. Everything that has been said so far is valid for CBEs irrespective of the country of use (providing, of course, their use is allowed in chocolate in the first place). Outside of the European Union, however, other options are possible, assuming that the fats are available. As well as the six base oils permitted in the EU, it is theoretically possible to use other fats such as pentadesma fat with a stearine rich in StOSt, allanblackia fat, also with a stearine rich in StOSt, aceituno fat with a stearine rich in both POSt and StOSt, mowrah butter with a stearine rich in POP, POSt, and StOSt, and even Chinese vegetable tallow, which is rich in POP. Each of these components are discussed in more detail in Chapter 4. Unfortunately, though, none of them are (yet) widely available commercially. When used in chocolate at, say, the 5% level, the CBE replaces part of the cocoa butter that is added to the recipe. Typical recipes for dark and milk chocolate with and without 5% CBE are shown in Table 9.3. As well as their use in chocolate at a level of, for example, 5%, CBEs can also be used at a much higher level replacing all of the added cocoa butter in chocolate. In this case, it is no longer permissible to call the product “chocolate,” but it is usually labeled as a “chocolate-flavored coating.” In the oils and fats and confectionery industries, though, it is often called a “supercoating” or “supercompound.” Because the triglycerides in the CBE part are the same as those in cocoa butter, a supercoating needs to be tempered in the same way as chocolate and, indeed, in many of its characteristics (melting, snap, flavor release, gloss, etc.) a good quality supercoating is indistinguishable from chocolate. It just cannot be called “chocolate.” Typical dark and milk supercoating recipes are shown in Table 9.4.
9.4 Use of tropical exotic oils (including shea butter) in fillings Fat-based confectionery fillings are not covered by the same well-defined restrictions as is chocolate. This means that, in theory, any edible oil could be used in a filling. In practice they tend to fall into two main groups—those containing nut pastes (which will be considered in Section 9.5) and those based on a vegetable oil with sugar and added flavors, colors, and so on, as appropriate. This is the simplest way of looking at such fillings because, in practice, their compositions vary widely. In terms of the vegetable oil base, though, commodity oils tend to be the most commonly used. Some
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Typical dark and milk chocolate recipes with and without 5% CBE Table 9.3
Cocoa mass Cocoa butter CBE Full cream milk powder Sugar
Dark chocolate (no CBE)
Dark chocolate (5% CBE)
Milk chocolate (no CBE)
Milk chocolate (5% CBE)
40 12
40 7 5
10 22
48
48
10 17 5 34 44
33.2
28.2 5.0
33.2
33.2
100
85.0 15.0
24 44
Fat composition Cocoa butter CBE Milk fat Total fat
27.3 6.5 33.8
22.3 5.0 6.5 33.8
Expressed as % of fat phase Cocoa butter CBE Milk fat Table 9.4
80.8 19.2
66.0 14.8 19.2
Typical dark and milk supercoating recipes
Cocoa mass CBE Full cream milk powder Sugar
Dark supercoating
Milk supercoating
40 12
10 22 24 44
48
Fat composition Cocoa butter CBE Milk fat Total fat
21.2 12.0 33.2
5.3 22.0 6.5 33.8
Expressed as % of fat phase Cocoa butter CBE Milk fat
63.9 36.1
15.7 65.1 19.2
confectionery fillings are based on cocoa butter. This obviously has the benefit of complete compatibility between coating and filling but is also expensive and, unless, the cocoa butter in the filling is softened with a more liquid oil, there are only limited textural differences between coating and filling.
Specialty oils and fats in confectionery231
More common is the use of palm oil or blends of palm fractions as the base of confectionery fillings. These have a number of advantages. Palm oil and its fractions are reasonably priced. The physical properties of both base oil and fractions are widely different meaning that a wide range of melting profiles and, therefore, filling textures can be produced by making different blends. Because palm mid-fraction is rich in POP, fillings containing palm mid-fraction have a good compatibility with chocolate. However, first, palm oil as a commodity is outside the scope of this book, and, second, some manufacturers are starting to move away from the use of palm-derived fats for reasons of either high levels of saturated fat or concerns about sustainability. Both of these concerns can be countered in the sense that any alternative with a similar melting profile is also likely to include some saturated fat, and that palm oil from sustainable sources is readily available. Nevertheless, these concerns are still there and often it is shea butter that comes in as an alternative. Figure 9.4 compares the melting profiles of palm oil and shea butter. Both oils have approximately the same level of saturated fat (about 50%), although this is predominantly palmitic acid in palm oil and stearic acid in shea butter. Because the saturates in shea butter are mainly stearic acid and because this is higher melting than palmitic acid the solid fat content of shea butter at any given temperature on its melting profile is higher than that of palm oil. For example, at 20 °C the solid fat content of shea butter is approximately twice that of palm oil. This means that in order to match the melting profile of a palm-based filling fat with one using shea butter it will be necessary to soften the shea butter. The obvious way to do this is to add some liquid vegetable oil, for example, rapeseed oil or even shea oleine. This not only brings the melting profile into line with that of the original filling but also reduces the saturates level in shea butter. Although shea butter is perhaps the most obvious oil to use in such fillings the basic premise can be used with any of the other exotic tropical oils (illipe, sal, kokum, mango kernel) to achieve an alternative filling fat composition. In all cases, compatibility of the filling fat with cocoa butter in a chocolate coating is maintained. 70 60
% Solid fat
50 40 30 20 10 0 0
10
20
30
40
Temp. ( C) Shea butter
Palm oil
Figure 9.4 Comparative melting profiles of palm oil and shea butter.
50
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As well as using fats in fillings that have a good compatibility with cocoa butter it is also common to find confectionery fillings that are based on lauric fats, which have limited or no compatibility with chocolate. Often these are based on palm kernel oil, particularly biscuit cream fillings, which are outside the scope of this book, but also fillings based on coconut oil are used. Both coconut oil itself and fully hydrogenated (and, hence, trans-free) coconut oil are used to give coolness to fillings. This is because of their very steep melting profiles, which go from fairly high levels of solid fat down to completely molten in a short temperature range just above ambient temperatures. This very rapid meltdown extracts latent heat from the mouth, which results in a cooling of the mouth and thus a cool sensation. This coolness can be enhanced by using dextrose in the filling and even by adding some peppermint oil to the filling. One of the main problems with using coconut oil, fully hydrogenated coconut oil, and also palm kernel oil in this way is that the oils are incompatible with cocoa butter and so any migration of filling fat into the chocolate will result in a softening of the chocolate and the possibility of fat bloom formation. The effects of combining cocoa butter and palm kernel oil, for example, are shown in Figure 9.5. The effects are very similar for interactions between cocoa butter and coconut oil. Even relatively low levels of oil migration from filling to coating will result in considerable softening of the chocolate. For example, 20% migration of palm kernel oil into the chocolate reduces the solid fat content at 20 °C from 76% to 55%; 40% migration will reduce the same solid fat content from 76% to 36% (Talbot, 2008). Migration to this extent will soften the chocolate
80 70
% Solid fat
60 50 40 30 20 10 0
0
20
40
60
80
% Palm kernel oil N20
N25
N30
Figure 9.5 Interactions between cocoa butter and palm kernel oil. Based on Talbot (2008).
100
Specialty oils and fats in confectionery233
so much as to make it very difficult to handle. One way in which the confectionery industry has overcome this is to dispense with the chocolate coating altogether and to sell coconut oil-based fillings as such, often in foil cups known as “ice cups.”
9.5 Use of tree nut oils Nuts as a whole and nut butters as filling pastes form an important part of both confectionery inclusions and centers. Perhaps the most common nut used in this way is the peanut, which, of course, grows underground and is not, therefore, a tree nut in the sense that hazelnuts, brazil nuts, walnuts, and almonds are. Hazelnuts are often used as inclusions both in the form of the whole nut and as chopped pieces. Brazil nuts are generally used as the total center; that is, the whole nut is coated in chocolate and marketed simply as the nut with a chocolate coating. Almonds can be used both whole (as inclusions in solid molded bars of chocolate) or chopped (as inclusions in filling). One of the most common uses of walnuts in confectionery is as a component in “walnut whips” in which a pyramid of chocolate containing a mallow filling is topped with a walnut. As far as nut oils are concerned, the main issue with these products is that there is the potential for these to migrate out of the nut into the chocolate, thus causing softening and, potentially, fat bloom. This is more of a problem with chopped nuts than with whole nuts because of the greater surface area. The whole problem of nut oil migration is greatly enhanced, though, when nut pastes are used as part of a filling composition because in paste form the nut oils are much more readily available to migrate. The use of nut pastes in confectionery fillings originated with the praline. The name praline is often thought to have originated with the seventeenth century Duke of Plessis-Praslin whose cook is supposed to have first coated whole almonds in caramelized sugar (Food Timeline, 2014). Over time this changed from coated whole nuts to a powdered version of the caramelized sugar-coated nuts. As well as this change, hazelnuts began to be commonly used as well as almonds. As the development of these fillings progressed it also became common to simply use a nut paste, often hazelnut paste, as a component in a confectionery filling, still usually known as a praline. A typical hazelnut paste-based filling recipe is (Talbot, 2014): Dark chocolate 15.0% Hazelnut paste 15.0% Full cream milk powder 10.0% Filling fat 20.0% Sugar 34.6% Chopped hazelnuts 5.0% Lecithin 0.4%
The filling fat is important because it helps to give structure to the whole filling, making it easier to handle as well as reducing the overall content of liquid nut oils that are available to migrate into the chocolate. Even small amounts of nut oil migrating from the filling into the chocolate can have a major effect on the shelf life and stability of the chocolate. Smith et al. (2008) found that even as little as 1% nut oil migrating
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into chocolate can accelerate the rate of polymorphic change from form βV to form βVI in chocolate, eventually resulting in fat bloom formation. Greater degrees of migration will both accelerate that rate of change and of bloom formation and will also result in a much softer chocolate. Using a filling fat that gives structure and reduces the overall level of hazelnut paste (oil) in the filling will help to reduce the rate and extent of migration and maintain a harder chocolate. The oils and fats company IOI Loders Croklaan (2014), for example, suggest a recipe using their filling fat Creamelt™ 501 to improve the structure of a hazelnut paste filling: Creamelt™ 501 40.0% Cocoa powder 5.0% Hazelnut paste 15.0% Full cream milk powder 5.0% Sugar 34.6% Lecithin 0.4%
To minimize the polymorphic transformation in the cocoa butter in the chocolate shell that can result in bloom as a result of nut oil migration, it is necessary to include an antibloom fat in the filling recipe (Smith et al., 2008). IOI Loders Croklaan (2014) also suggests such a formulation using Prestine™ 34F, an antibloom filling fat: Prestine™ 34F 28.0% Hazelnut paste 20.0% Full cream milk powder 3.0% Skimmed milk powder 4.0% Sugar 44.6% Lecithin 0.4%
9.6 Use of essential oils The use of triglyceride-based botanical oils in confectionery is quite limited but the use of essential oils is more common. These are oils that will give some form of flavor either to chocolate or to a filling, and the use of mint oil, orange oil, and lemon oil is quite common. In addition to these, rose oil is also used in Turkish Delight recipes. In scientific terms, perhaps one of the most interesting series of studies using oils such as these in chocolate is the one concerned with the effect of limonene on the properties of chocolate. One of the main problems in reducing the fat content of chocolate is that removing fat increases the viscosity, making the chocolate more difficult to handle. Do et al. (2008) found that adding limonene to chocolate considerably reduced its viscosity, thus opening the door to the possibility of more easily producing a low-fat chocolate. The disadvantage was that, as well as reducing the viscosity of the chocolate, it also reduced its hardness. Ray et al. (2012) took this one stage farther and found that the addition of limonene to chocolate enhanced the production of lower polymorphic forms (α and β′IV) on cooling but then accelerated their transformation into the more stable βV form.
Specialty oils and fats in confectionery235
9.7 Use of structured triglycerides The background to and the production of structured triglycerides is considered in detail in Chapter 8. As an introduction to this section all that needs to be said is that structured triglycerides are triglycerides that are produced, often by enzymic interesterification, that are either not found in natural oils and fats or are limited by availability. As far as confectionery uses are concerned, there are a number of different types of structured triglycerides that have been used, each with different applications. Possibly the main group of these triglycerides are the SOS types; that is, triglycerides similar to those found in cocoa butter. Mention has already been made in this chapter of the difficulty of sourcing oils rich in POSt to match the POSt content of cocoa butter in a CBE. Illipe and aceituno stearine are the only alternative sources and these are either variable or limited in availability. However, using a triglyceride rich in 2-position oleic acid (for example, high oleic sunflower oil or palm oleine) and enzymically interesterifying this with a mix of palmitic and stearic acids will give an end product that contains significant levels of POSt (as well as POP and StOSt). It will need to be cleaned up by a combination of fatty acid removal and fractionation but the end product is either a CBE in its own right or a very useful component of a CBE. In a similar way, an end product rich in StOSt can also be produced. This process was developed by Unilever, largely as a means of supplementing the availability of POSt and StOSt at times of restricted availability of illipe and shea (Macrae, 1983). Since then the process has broadened widely in both the types and applications of triglycerides produced in this way and also in the use of these cocoa butter-like triglycerides in confectionery. The point made in Section 9.3 that the use of this process to produce the vegetable fats permitted in EU chocolate is prohibited needs to be reiterated. However, this exclusion only applies to the EU and enzymically produced POSt and StOSt are used in CBEs in other countries where these are allowed. A specific type of SOS that is produced in this way is BOB (1,3-dibehenyl, 2-oleoylglycerol). This was developed by the Fuji Oil Company in Japan and incorporates two behenic acid (C22:0) groups in the 1- and 3-positions of the triglyceride as well as the more usual oleic acid group in the 2-position. Because it is still a SOS triglyceride it has excellent compatibility with cocoa butter but, because of the two high-melting behenic acid groups, it has a much higher melting point (53 °C) than cocoa butter. Its main uses are as a seed to temper chocolate and as an antibloom fat. If a small amount of BOB is incorporated into chocolate and that chocolate then melts because, for example, it has been stored at a very high ambient temperature, then, unless the storage temperature is excessively high, the BOB will remain in the chocolate in a solid state. When the chocolate cools back down again the BOB will reseed the chocolate and, therefore, prevent the bloom formation that would otherwise occur (Koyano et al., 1990). The behenic acid is obtained from the complete hydrogenation of high-erucic acid rapeseed oil. This is the original type of rapeseed oil that used to be grown widely many years ago until it was found that the erucic acid (C22:1) in the oil was implicated in raising the risk of heart disease. As a result of plant breeding work, a new variety of rapeseed oil (also known as canola oil) was produced that,
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Specialty Oils and Fats in Food and Nutrition
instead of being rich in erucic acid, is rich in oleic acid. This is the variety that is now grown widely across North America and Europe, almost to the exclusion of the original high-erucic variety. However, there is still a small amount of the original crop grown for very specific uses such as this in which the erucic acid is converted into behenic acid by hydrogenation. Another use of behenic acid in a structured triglyceride is in the production of Caprenin™. Caprenin™ was developed by the Proctor and Gamble Company as a low-calorie CBR. It is composed of caprylic (C8:0), capric (C10:0), and behenic (C22:0) acids. Capric and caprylic acids are produced from coconut oil and together comprise a group of structured triglycerides known as medium-chain triglyceride oils. These have very specific uses in both sports and postoperative nutrition because they deliver energy to the body differently than longer-chain triglycerides and also have a slightly lower calorie content. Behenic acid, on the other hand, is so high-melting that it effectively passes through the body unabsorbed. The result of combining these fatty acids together in a single triglyceride is one that not only melts close to the melting temperature of cocoa butter but also has a lower calorific content (said to be about 5 kcal/g). Another structured triglyceride that is used in confectionery and that has a lower calorific content than conventional triglycerides is Salatrim®, now known as Benefat®. Salatrim® is an acronym for Short And Long-chain Acyl TRIglyceride Molecules. The short-chain acids are acetic (C2:0), propionic (C3:0), or butyric (C4:0) acids while the long-chain acid is usually stearic acid (C18:0) obtained by complete hydrogenation of liquid oils such as soyabean, rapeseed, sunflower, or cottonseed. These are interesterified in triglyceride form and triglycerides with either three short-chain or three long-chain acids are removed. Benefat® is produced by Danisco and is available in a number of forms, one of which is suitable as a partial CBS. It can be used at levels of up to 10% in place of cocoa butter in chocolate-like products, but because it does not give a “snap” to the product cannot be used in molded bars (Danisco, 2014). It does, though, find application in chocolate chips for use in baking. It has a calorific content of 6 kcal/g.
9.8 Future trends This chapter has been divided into sections intended to reflect some of those in the first part of this book. In terms of future trends, we can try to predict these using the same basic section headings.
9.8.1 Tropical exotic oils As far as EU chocolate is concerned, it took a long time for all the parties concerned to come to an agreement that resulted in the Chocolate Directive of 2000 (European Union, 2000). It is likely, therefore, to take an equally long time to change any of the restrictions placed on the use of vegetable oils in chocolate in that directive. This
Specialty oils and fats in confectionery237
means that the six base oils defined in the legislation are likely to remain there for some years to come, thus preventing the use of oils with similar triglyceride compositions that are not on the permitted list from being used. Having said that, the main oils in use are still palm oil and shea butter with lesser amounts of sal oil and illipe butter being included. Scope exists, therefore, for greater production and use of the other oils, kokum, and mango kernel. Although palm oil will remain as the main vegetable oil used globally for many years to come, there will still be some pressure on it in more niche markets in terms of its level of saturation and particularly in terms of environmental concerns. This is likely, then, to open the door to a greater usage of shea butter and its fractions, especially if these can be supplied in an organic, sustainable, and fairly traded form. Other tropical exotic oils may also start to come more into the mainstream. Unilever’s interest in allanblackia oil, while not being specifically confectionery related, may help to bring it into use in some areas of the world as a confectionery fat. Similarly, there is interest in Sri Lanka in converting some of the land used to grow tea into areas for pentadesma cultivation. This would then bring another potential CBE component onto the market.
9.8.2 Tree nut oils As manufacturers look for new product ideas, new tree nuts may well come into use in confectionery products. So, as well as the mainstream hazelnut, almond, and brazil nut, we are already seeing, for example, chocolate-coated macadamia nuts. Cashew nuts are not often seen in confectionery products but are a popular “snacking” nut— perhaps there is scope for a greater use of these in confectionery.
9.8.3 Botanical oils The use of triglyceride-based botanical oils in confectionery is quite limited so, as the use of these increases in other areas, there may be some applications in chocolate confectionery. Examples could be a focused use of, for example, evening primrose oil in confectionery targeted at women, or the incorporation of omega-3-rich oils (e.g., flaxseed) or oils such as blackcurrant seed oil with its interesting mix of omega-3, omega-6, and stearidonic acids.
9.8.4 Structured triglycerides The whole area of structured triglycerides is one that is likely to continue to develop and new base oils are likely to be used, even to produce triglycerides such as StOSt that can already be made using this technology. As an example, a CBR has been developed from the enzymatic interesterification of hydrogenated and fractionated tea seed oil (Zarringhalami et al., 2010). Similarly, a cocoa butter analogue has been produced from camel hump fat (Shekarchizadeh et al., 2009). It is also likely that new structured triglycerides will be introduced into confectionery that are either lower calorie or that are suitable for sports and other types of nutrition.
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References Beckett, S.T. (Ed.), 2009. Industrial Chocolate Manufacture and Use, fourth ed. WileyBlackwell, Oxford. Chaiseri, S., Dimick, P.S., 1989. Lipid and hardness characteristics of cocoa butter from different geographical areas. J. Am. Oil Chem. Soc. 66, 1771–1776. Danisco, 2014. Benefat® reduced calorie triglycerides. http://www.aditiva-concepts.ch/ download/BENEFAT.pdf (accessed 15.05.14). Do, T.-A.L., Vieira, J., Hargreaves, J.M., Wolf, B., Mitchell, J.R., 2008. Impact of limonene on the physical properties of reduced fat chocolate. J. Am. Oil Chem. Soc. 85, 911–920. European Union, 2000. Directive 2000/36/EC of the European Parliament and of the Council of 23 June 2000 Relating to Cocoa and Chocolate Products Intended for Human Consumption. Food Timeline, 2014. FAQs candy. http://www.foodtimeline.org/foodcandy.html#praline (accessed 14.05.14). IOI Loders Croklaan, 2014. Filling fats. pp. 7, 15. http://europe.croklaan.com/images/static_ pages/Filling_Fats_English.pdf (accessed 14.05.14). Jurriens, G., 1968. Analysis of triglycerides. In: Boekenoogen, H.A. (Ed.), Analysis and Characterisation of Oils and Fats and Fat Products, vol. 2. Interscience Publishers, London. p. 279. Koyano, T., Hachiya, I., Sato, K., 1990. Fat polymorphism and crystal seeding effects on fat bloom stability of dark chocolate. Food Struct. 9, 231–240. Lipp, M., Anklam, E., 1998. Review of cocoa butter and alternative fats for use in chocolate— Part A. Compositional data. Food Chem. 62, 73–97. Macrae, A.R., 1983. Lipase-catalyzed interesterification of oils and fats. J. Am. Oil Chem. Soc. 60, 291–294. Ray, J., MacNaughton, W., Chong, P.S., Vieira, J., Wolf, B., 2012. The effect of limonene on the crystallisation of cocoa butter. J. Am. Oil Chem. Soc. 89, 437–445. Richter, K., 2009. Tempering process technology. In: Talbot, G. (Ed.), Science and Technology of Enrobed and Filled Chocolate, Confectionery and Bakery Products. Woodhead Publishing, Cambridge. Shekarchizadeh, H., Kadivar, M., Ghaziaskar, H.S., Rezayat, M., 2009. Optimization of enzymatic synthesis of cocoa butter analog from camel hump fat in supercritical carbon dioxide by response surface method (RSM). J. Supercrit. Fluids 49, 209–215. Smith, K.W., 2009. Ingredient preparation: the science of tempering. In: Talbot, G. (Ed.), Science and Technology of Enrobed and Filled Chocolate, Confectionery and Bakery Products. Woodhead Publishing, Cambridge. Smith, K.W., Zand, I.T., Talbot, G., 2008. Effect of anti-bloom fat migration from a nut oil filling on the polymorphic transformation of cocoa butter. J. Agric. Food Chem. 56, 1602–1605. Talbot, G., 2006. Application of Fats in Confectionery. Kennedy’s Publications, London. Talbot, G., 2008. Interactions between coating fats and filling fats. In: Lecture Given at ZDS Chocolate Technology Conference, Cologne. Talbot, G., 2009a. Fats for confectionery coatings and fillings. In: Talbot, G. (Ed.), Science and Technology of Enrobed and Filled Chocolate, Confectionery and Bakery Products. Woodhead Publishing, Cambridge. Talbot, G., 2009b. Compound coatings. In: Talbot, G. (Ed.), Science and Technology of Enrobed and Filled Chocolate, Confectionery and Bakery Products. Woodhead Publishing, Cambridge. Talbot, G., 2014. Fats for chocolate and sugar confectionery. In: Rajah, K.K. (Ed.), Fats in Food Technology, second ed.
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Unilever, 1956. Improvements in or relating to cocoa butter substitutes. GB Patent 827172. Wille, R.L., Lutton, E.S., 1966. Polymorphism of cocoa butter. J. Am. Oil Chem. Soc. 43, 491–496. Zarringhalami, S., Sahari, M.A., Barzegar, M., Hamidi-Esfehani, Z., 2010. Enzymatically modified tea seed oil as cocoa butter replacer in dark chocolate. Int. J. Food Sci. Technol. 45, 540–545.