Food science reviews, vol. 2: Chemical migration from food packaging

BookReviews sampling, all of the others discuss several important topics are not covthe following topics: the character- ered comprehensively enough. Thus, istics of the pathogens, isolation except in the case of the two exceland identification procedures, mech- lent chapters on mycobacteria, the anisms of contamination, incidence, information provided on the epidemipathogenicity, epidemiology, and pre- ology, incidence (particularly some vention and control. Although all available published data from devel11 chapters dealing with pathogens oping countries), control and prevenare organized in a somewhat similar tion seems to be insufficient. The manner, their presentation is uneven, inclusion of more information relative as are the discussions of the differ- to these topics would certainly have ent topics within each chapter. For improved these chapters. Also, it example, certain authors focus on would have been relevant and useful the characteristics of pathogens, others to include a chapter on some sporeon the methods of isolation and identi- forming pathogens, such as Bacillus fication. cereus, that have a public health In addition, the title of the mono- significance mainly in heated milk graph may be misleading, as the book products. does not emphasize the significance The text is generally well written of pathogens in raw milk, particularly in spite of a few typographical erthe public health hazards from the rors, and illustrated with several multiplication of pathogens in raw tables. The chapter on milk sampling milk and in products made from it, contains numerous photographs, as well as the ecological conditions enabling the reader to visualize the enhancing these hazards. In general, various operations involved in milk the monograph encompasses a broad sampling. Each chapter ends with a subject area and as a consequence list of references cited in the text,

Food Science Reviews, Vol. 2: Chemical

Migrationfrom FoodPackaging editedby D.H. Watsonand M.N. Meah,EllisHorwood,1993.£15.95(vi + 159 pages)ISBN0 13 0585475

The general topic of chemical migration from food packaging materials has a long history. However, even to this day, this topic is widely misunderstood by government agencies responsible for food safety, by the general public who hear about such things from the media, and even by scientists who work in the field. I believe the main reason for this misunderstanding is a combination of the difficulty in gathering appropriate data together with the problems associated with deciding what is considered to be appropriate data. Volume 2 of Food Science Reviews does a good job of illustrating this problem of migration by covering recent European Community (EC) efforts to control migration from packaging into foods and a selection of representative current research. Part 1, 'Migration tests for food packaging', provides a useful survey of the various types of both global and specific migration tests that would meet the requirements of EC directives on plastic materials and

articles coming into contact with foodstuffs. Current developments include the control of the migration of monomers from the plastics, while the control of additives is not far behind. The information presented is not developed with any great rigor, but it does provide practical information about the types of testing methods involved and the most common problems associated with providing migration limits Part 2, "EC legislation on food contact materials and articles', is mairdy a listing of the names of EC directives on chemical migration from food contact materials and articles. Some effort has be,~-n made to review the details of the key directives, but only briefly. Part of the problem is that packaging innovations are raising questions that have not been considered previously and, thus, the details of testing methods are not yet developed. Part 3, 'Migration testing food contact plastics for high temperature applications', presents much useful information about experimental techniques for testing materials at elevated

allowing the reader to obtain more detailed information if desired. In this respect, the chapters on mycobacteria and viruses have extensive and very adequate bibliographies. However, in other chapters, a majority of the references listed could he considered outdated as more recent information is available. Despite its shortcomings, including some lack of depth, the monograph should be regarded as an important initial attempt to gather relevant information concerning pathogenic microorganisms in milk and milk products; in fact, there are not too many books dealing specifically with this subject at the present time. The monograph is particularly recommended for dairy industry professionals, public health personnel as well as academicians and students working in the dairy science field. Abed Hamama InstitutAgronomlqae et V~.n'naire Has:sanIi, Rabat,Morocco.

temperatures, such as those temperatures to which plastics in contact with foods are often exposed in microwave ovens. The description of the heating and application of simulants to te~t surfaces heated at temperatures above 175°C is especially good. Developments in the handling of the migration of volatiles and the use of alternative simulants, which are, to my knowledge, right at the frontier, are also discussed. Part 4, 'Migration from boil-in-bag laminates', contains a highly detailed description of the plastic and adhesive components comprising boilin-bag compositions, and the wide range of analytical capabilities required to identify and quantify the various migrants arising from such compositions. The fabrication and use of boil-in-bag materials are also discussed. The point that the highly sophisticated analysis instruments necessan/ for this work are not usually found in the average industrial laboratory is well made. Thus, the problem of how such methodology can be applied by suppliers, converters or retailers is a serious one that remains to be solved. Part 5 is entitled 'To what extent is packaging used for storing food and drink in the home.~' After a very brief review of the existing methodology that is employed to determine the

Trendsin FoodScience& TechnologyMay 1995 IVol. 6]

extent to which food and drink packaging materials are used in the home, the authors desc:ibe the results of a study performed in 1992 that involved nearly 1000 consumers being interviesved, and then diary studies being carried out on -200 of the consumers. The study focused on the use of cling film and tin cans. Details regarding the age and socioeconomic distributions of the interviewees are given. The results include the usage of different types of cling films, the frequency of use and what types of foods they are used for (mostly sandwiches, cooked meats and cheeses). The data pertaining to tin cans were concerned with the length of time they were stored for and whether stored tins were rotated to use the older ones first. Some data are also given about the usage of glass bottles and foil-lined cartons. The authors point out the uniqueness of the data, and therefore the concomitant difficulty of checking their accuracy owing to the lack of

To bring together within one volume all aspects of food flavourings must have been a difficult task, and the fact that this revised second edition comes soon after the reprinting of the first edition indicates the usefulness of the book. The spelling of its title might suggest a US authorship; however, throughout the book, 'flavour' is consistently spelt in the UK way, and indeed if the book has a weakness then it is its preoccupation with the UK food and flavour industry. This is a pity as with a slight change in emphasis it could have been given a much more international or at least a European perspective. The opening chapter on the control of quality, which is new to this edition, covers a topic of current and active interest to many food and flavour manufacturers seeking ISONORM status for their development and manufacturing operations. It gives a concise and readable description of the necessary steps leading to BS5750 accreditation, and highlights the problems and key issues that need to be addressed along the way. This chapter together with its references provides a very useful introduction to this topic for any company planning such an exercise. The next four chapters are devoted to the major classes of raw materials used for flavour manufacture. The

comparable data. However, this study represents a start and has turned up some of the factors that should be considered when gathering such data, especially if they are intended to be used as a basis for quantifying the levels of chemical migrants from packaging that are taken in by consumers. Crude methods of estimating exposures to chemical migrants do not appear to be adequate for risk assessment purposes. Part 6, 'Modelling chemical migration from packaging into food', reviews the mathematical models that are used to predict the migration of chemicals from packaging into foods. These include diffusion-controlled migr~tior~, with key examp!~'~ .b,~ing cited from the literature, and permeation through laminates. The models that have been selected are appropriate and representative of the range of models available today, especially for plastic packaging systems. This part of the book also correctly points out the fact that much effort has been

devotedto d ~ s ~ l ~ d modds ~ the migration of chemicals from food packaging, but veil/ little has been expended on l~le experimental evaluation of the n~.,Is. Thisonh, empl~asizes the pmblmm confronting ler,blators who are developing methods for conlrolling migration from films into foods. Overall, the book does meet the stated objectives in that it presents a timely series of reviews on the developing EC controls on chemical migration from packaging, and also on efforts to develop suitable methods of testing lhat will make control practk:abte. Thus, the book is likely to be. of interest mainly to ~_hosewho wish to know about such developments.

c.~,p w. Halek Dep.~me~d r-~d Sc-~ce,

NI 0~03-0231, USA.

Food Flavorings (2nd edn) editedby P.R.Ashurst,Blackie, 1994.£75.(~0(xvii + 332 pages)ISBN0 75140228 1

first three of these give a useful introduction to the nonspecialist on the most important groups of natural raw materials used by the flavour industry. That on essential oils gives a brief but useful overview of the main methods of production, followed by a description of the most important essential oils, their sources and uses. The chapter on oleoresins, tinctures and extracts follows a similar approach and describes their manufacture and origins; this covers not only the classical techniques of production but also the more recent use of super- and sub-critical CO2 as an extraction solvent, and lists some (but not all) suppliers of extracts made in this way. Fruit juices are discussed in a separate chapter that describes the processing and packaging of the main juice types, their specifications and uses. The remaining chapter concemed with raw materials describes chemically synthesized ingredients and gives an excellent review of the subject. This chapter has an extensive llst of references and gives the reader a good introduction to the complexity of flavour chemistry by relating

Trendsin FoodScience& TechnologyMay ;995 [V01.6]

chemical structures to flavour notes. The organic chemistry described in the chapter should be sufficient to satisfy the scientific reader without deterdng the non-chemist and, most importantly, it manages to convey something of the creative and scientific blend of skills required by the flavourist. The next three chapters of the book turn to the application of flavours in finished food products. Flavouring of beverages is very much oriented to the specialities of the UK market with, for example, a fairly lengthy discussion about beverages based on ginger. The chapter covers other traditional beverages in fairly general terms but surprisingly makes no mention of more recent developments in the beverage industry such as flavoured, herbal or iced tea, where the use of flavourings is significant. The two chapters on confectionery and bakery products that appear in the first edition of the book have been merged into a single revised chapter in this second edition, which gives a useful review of the different product categories and issues concerned

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