Microencapsulation of Grape Seed Extracts

CHAPTER 18

Microencapsulation of Grape Seed Extracts ˜igo Arozarena1, Montserrat Navarro1 and Gabriel Davidov-Pardo1,2, In Marı´a R. Marin-Arroyo1 1

Department of Food Technology, Ænoltec research group, Public University of Navarre, Pamplona, Spain 2Department of Food Science, University of Massachusetts, Amherst, MA, USA

18.1 Introduction Winemaking usually starts by destemming and crushing grapes; then, depending on the type of wine, crushed grapes are pressed, and skins are removed before fermentation to obtain white wine, or the skins remain in the must during fermentation, enabling the extraction of components from skins for red wine. The solids separated by pressing, called grape marcs or grape pomace, contain not only the skins but also the seeds and stems (if not previously separated). As a consequence, during the vinification processes a great amount of byproducts are generated: stems represent 3 7% of the weight of the bunch, and marcs represent around 20% of the raw material weight. This means that the world wine industry alone generates around about 13 14 million tons of marcs each year. Grape skins, seeds, and stems are rich in phenolic compounds. Grape phenolics have attracted great interest based on reports of their anti-oxidant properties and their ability to scavenge free radicals, and more recently for their antibacterial (Badet, 2011; Baydar et al., 2006; Chedea et al., 2011; Corrales et al., 2009; Jayaprakasha et al., 2003) and antifungal effects (Mendoza et al., 2013). By-products of grape processing are an abundant and inexpensive source of polyphenols, and their extraction and use will provide added value to the vinification residues, as well as contribute to the reduction of pollution in wine regions. In the case of white wine processing, the phenolic composition of seeds and peel wastes must be assumed to be very similar to that of the raw grapes. With regard to red wine processing, some of the phenolic compounds are transferred to the wine, particularly from the peels, which show greater polyphenol extractability during fermentation than do seeds. Peels from marcs have greater moisture and lower but more complex phenolic burden compared to seeds (Makris et al., 2007). They are particularly interesting as a source of anthocyanins, mainly the malvidin 3-monoglucoside. They also contain appreciable

Microencapsulation and Microspheres for Food Applications. DOI: http://dx.doi.org/10.1016/B978-0-12-800350-3.00023-6 © 2015 Elsevier Inc. All rights reserved.

351

352 Chapter 18 amounts of flavan-3-ols and, to a lesser extent, flavonols (mainly myricetin and quercetin 3-glucosides and 3-glucuronides), stilbenes (mainly trans-resveratrol), and phenolic acids (mainly caftaric acid) (Castillo-Mun˜oz et al., 2007; Chira et al., 2008). This chapter focuses on grape seeds, which are the main raw material commercially employed to obtain rich polyphenolic grape extracts. The phenolic content of grape seeds may range from 5% to 8% by weight depending on the variety (Shi et al., 2003). In addition to phenolic compounds, grape seeds also contain lipids (13 19%), proteins (11%), and indigestible carbohydrates (60 70%) (Rao, 1994). Quantities of polyphenols in seeds have been shown to depend on maturity stage (Kennedy, 2000; Shi et al., 2003) and environmental and agroecological factors (Shi et al., 2003; Cheynier, 2012), while seed phenolic profile depends on grape cultivar (Cheynier, 2012; Kammerer et al., 2004; Shi et al., 2003). Grape seeds are particularly rich in phenolic acids and flavan-3-ols (Kammerer et al., 2004; Makris et al., 2007), whereas minor amounts of flavonols, stilbenes, and anthocyanins can be detected, which must be ascribed to diffusion from the skins into the seeds during mashing and vinification (Kammerer et al., 2004). The polyphenol content of seeds is generally higher than that of the skins (Kammerer et al., 2004), with no significant differences between red (2.28 18.76 g/kg dry matter) and white grape cultivar seeds (3.52 13.63 g/kg dry matter). Though only a part of the total phenolic compounds is extractable (60 70%, according to Shi et al., 2003), grape seeds have great potential to serve as a rich source of phenolic extracts. In recent years, the high phenolic content and the properties of the polyphenols have made grape seeds a focus of major scientific and applied interest. A substantial number of studies deal with the extraction of the phenolic compounds, their characterization, and the study of the extracts’ functionality. Yu and Ahmedna (2013) have extensively reviewed the recent studies on grape pomace components, properties, and potential applications, providing specific data for seeds. The main phenols contained in grape seeds exhibit a high anti-oxidant power—20 times greater than vitamin E and 50 times greater than vitamin C (Shi et al., 2003)—and a higher anti-oxidant activity compared to the synthetic food anti-oxidants BHT and ascorbyl palmitate (Lafka et al., 2007). Their biological, anti-oxidant, and antimicrobial properties make grape seed extracts (GSE) a candidate for many applications: (i) GSE can play an important role as health-promoting food ingredient; (ii) in the substitution of synthetic food anti-oxidants by natural ones, it can be added directly in food formulations or incorporated in edible films; (iii) in the formulation of cosmetics; or (iv) as an alternative to synthetic fungicides for the management of plant diseases.

Microencapsulation of Grape Seed Extracts 353 On the other hand, several disadvantages have emerged for the direct use of these extracts: (i) when GSE is incorporated into food products in its regular form, phenolic compounds can have a negative impact on food quality. It is well known that the interaction between polyphenols and proteins or polysaccharides can cause some undesirable effects such as alteration of color stability, haziness in drinks, and even the appearance of precipitates (Cheynier, 2012; Shi et al., 2003); (ii) the complexation of polyphenols with enzymatic proteins may result in their inhibition, affecting the bioavailability of certain food components; (iii) interaction of tannins with salivary proteins is believed to be responsible for the perception of astringency, and phenolic compounds exhibit taste properties such as bitterness; (iv) GSE is sensitive to oxidation, epimerization, hydrolization of moieties, and polymerization at high temperatures, and most processed food products undergo heat treatments during their production process. Subjecting GSE to thermal treatments commonly used in the food industry, such as pasteurization and sterilization, in most cases changes the phenolic profile as well as the color and anti-oxidant activity of the extracts (Davidov-Pardo et al., 2011b). As a consequence of these transformations, GSE can lose anti-oxidant activity or change to a darker brown (Chamorro et al., 2011; Davidov-Pardo et al., 2011b; Ross et al., 2011). (v) Finally, GSE is composed mostly of condensed tannin, which limits its bioavailability; the polyphenols in the extracts have different bioavailabilities, depending mainly on their size. Monomers are rapidly absorbed and metabolized, while proanthocyanidins are hardly absorbed at all: only 5 10% of the dimers are absorbed compared to the monomers, and are mostly metabolized by the colonic microflora (Aron and Kennedy, 2008; Hollman et al., 2011; Ou and Gu, 2014). Microencapsulation can provide solutions to overcome most of these drawbacks. Encapsulation can protect GSE against chemical, physical, or biological degradation, as well as mask the unpleasant taste of polyphenols. Encapsulation can also prevent or reduce interaction with proteins, and therefore avoid astringency and inhibition of enzymes. Anti-oxidants are often encapsulated to improve their bioavailability and compatibility with the food matrix (McClements, 2012). Microencapsulation can also improve storage, handling, and utilization, and extend the shelf life of the extracts. This chapter will present a detailed description of the phenolic compounds contained in grape seeds, an overview of different encapsulation methods, and specific examples of microencapsulation applied to GSE.

18.2 Phenolic Compounds and Oil from Grape Seeds As cited before, seeds are the grape by-product with the greatest amount of total phenolic compounds, basically of the flavonols group, with loads between 1 and 6 g/kg of grape fresh weight (Chira et al., 2008). Monomeric flavanols are mainly (1)-catechin and (2)-epicatechin. They can also be sterified with gallic acid: (2)-epigallocatechin-gallate,

354 Chapter 18 (2)-epigallocatechin, and (2)-epicatechin-gallate. Monomeric flavan-3-ols are combined to form oligomers [2 to 5 (1)-catechin and/or (2)-epicatechin units] and polymers, called condensed tannins or proanthocyanidins. Some dimers and trimers have been found and characterized in grape seeds, such as procyanidins B1 [(2)-epicatechin-(1)-catechin], B2 [(2)-epicatechin-(2)-epicatechin], B3 [(1)-catechin-(1)-catechin], B4 [(1)-catechin(2)-epicatechin], B2G [(2)-epicatechin-(2)-epicatechin-gallate], and C1 [three (2)-epicatechin units]. However, around 75 82% of seed procyanidins belong to a wide variety of polymeric chains of six or more monomeric flavonol units (Curko et al., 2014; Monagas et al., 2003). The individual characterization of these polymers is actually far from being concluded. Several techniques have been applied in order to separate the polymers according to size and, subsequently, characterize the mean polymerization degree (mPD) and level of galloylation of each fraction. These proanthocyanidin structural parameters have been found to be correlated with perceptions of astringency and bitterness. The higher the mPD and the percentage of galloylation of the proanthocyanidin fraction in the seed, the greater their astringency intensity (Curko et al., 2014; Vidal et al., 2003). Another important component of grape seeds is oil. The fatty acid profile of grape seed oil includes a great proportion of polyunsaturated fatty acids, mainly linoleic acid (C18:2, 65 73%), whereas oleic acid (C18:1) ranges between 14% and 22%; saturated palmitic (C16:0) and stearic acids (C18:0), represent around 7% and 5%, respectively (Fernandes et al., 2013; Lutterodt et al., 2011; Matthaeus, 2008). Grape seed oil contains appreciable amounts of tocopherols and tocotrienols (Fernandes et al., 2013; Matthaeus, 2008). With regard to the polyphenols, when the oil is obtained exclusively by pressing, the transfer of phenolic compounds from the seed cake seems to be very weak (Matthaeus, 2008), probably due to the low solubility of low molecular weight phenolics in the oil (Lutterodt et al., 2011). The combination of pressing by other methods, such as supercritical CO2 extraction or gas-assisted mechanical extraction could increment polyphenolic co-extraction, although it reduces the oil yield of the process (Rombaut et al., 2014). Figure 18.1 shows a general procedure in order to obtain oil and/or polyphenol-rich extracts from grape seeds. A complete revision of the suitable methods and the main factors that affect the extraction of phenolics from grape by-products is presented in Davidov-Pardo et al. (2014). Conventional batch solid liquid extraction is the most commonly used method to extract polyphenols from grape seeds. The seeds, previously dried or not, are crushed or milled until they reach a particle size of around 0.5 mm or lower, in order to increase the surface contact between the solid and the solvent. Defatting is sometimes applied, but is not essential because of the great difference in polarity between the oil and the solvents usually used to extract the polyphenols. The selection of these solvents affects the process yield and the relative phenolic composition of the extract. For hygienic and economic reasons and because of its compatibility with alimentary applications, the most common solvent is a combination of ethanol and water, with an optimum proportion around

Microencapsulation of Grape Seed Extracts 355 Grape seeds Pre-treatments Cleaning Drying Size reduction

Solvent Residual solids

Phenolics extraction

Seed cake

Crude grape seed extract (liquid)

Virgin grape seed oil

Solvent extraction

Post-extraction treatments Fractionation Evaporation Spray/freeze drying

(Screw) pressing

Solvent Refined grape seed oil

Grape seed extract (solid)

Figure 18.1 Schematic representation of the processes involved in the production of polyphenolic extracts and oil from grape seeds.

50% (Bucic-Kojic et al., 2007; Makris et al., 2007; Vatai et al., 2009). Sometimes the solvent is acidified, because lower pH facilitates the hydrolysis of lignocellulosic structures and the release of low molecular weight phenols. With regard to the solvent-to-solid ratio, 10:1 to 40:1 (mL/g) are the proportions usually used. Temperature is another important factor. To obtain phenolic extracts from grape seeds, better results appear to occur at temperatures between 50 C and 80 C (Bucic-Kojic et al., 2007; Pinelo et al., 2005; Vatai et al., 2009). Once the crude liquid extract is separated from the seed residual solids, it is subjected to additional operations to obtain a stable product; the most common operation is drying it into a powder. On commercial scales, spray drying is preferred due to its higher productivity and lower cost of investment and performance compared to freeze-drying, which is a more benign alternative in preserving the quality of the final product. Figure 18.2 shows the variations in phenolic composition and anti-oxidant activity in five commercial GSEs from different geographic origins (China, France, Spain, and the United States). On average, the monomeric flavan-3-ols (1)-catechin and (2)-epicatechin represent 37% and 32% of the total individual phenolic compounds quantified by HPLC, respectively, followed by procyanidins B2 (12%) and B1 (9%), the sum of (2)-gallocatechin, (2)-epigallocatechin-gallate, (2)-epigallocatechin, and (2)-epicatechingallate (around 9%), and free gallic acid (1.2%). All these low molecular weight compounds jointly account for around 132 mg/g dw, 15% of the total phenolics measured

356 Chapter 18 Gallic acid

(106)

Sum of individual compounds (mg/g dw) = 79 – 185 (32) Total phenolic content (mg GAE/g dw) = 801 – 926 (7)

(–)–Epicatechin-gallate

(141)

(–)–Epigallo-catechin-gallate

Anti-oxidant activity (mmol Trolox/g dw) = 5.7 – 6.2 (3)

(72)

(–)–Epigallo-catechin

(58)

(–)–Gallo-catechin

(59) (34)

Procyanidin B1

(23)

Procyanidin B2 (–)–Epicatechin

(31)

(+)–Catechin

(40)

0

10

20 30 40 50 60 Range of concentration (mg/g dw)

70

80

Figure 18.2 Range of concentration of phenolic compounds and anti-oxidant activity in five commercial grape seed extracts (GSE). In parentheses, the relative standard deviation. All the variables are expressed per gram of GSE dry weight. Total phenolic content and anti-oxidant activity were measured by the Folin Ciocalteu and DPPH methods, respectively. GAE, gallic acid equivalents (Davidov-Pardo et al., 2011a,b).

through the Folin Ciocalteu method (870 mg of gallic acid equivalent/g of dry weight). Although measuring procedures are not directly comparable, the difference between the two values suggests that the major part of the polyphenols in these commercial GSEs corresponded to oligomeric and polymeric compounds that could not be individually separated and quantified by HPLC. Finally, it must be noted that, in addition to conventional solid liquid extraction, novel techniques have been applied in order to improve the yield and quality of the polyphenolic extracts. These include the use of microwaves, ultrasound, enzymes, pulsed electric fields, high-voltage electrical discharges, or pulsed ohmic heating to assist the solid liquid extraction at atmospheric pressure, or the use of supercritical fluids, pressurized liquid, and subcritical water extraction techniques (Davidov-Pardo et al., 2014).

18.3 Microencapsulation: General Concepts Microencapsulation is a technique in which a material or mixture of materials is covered by other materials or material systems. This technique consists in the isolation of active substances

Microencapsulation of Grape Seed Extracts 357 within a micrometric-size particle. Usually, the active material is shielded from the surrounding environment by one or more layers of wall material (the wall material can be also referred as encapsulant, shell, or carry material) (Madene et al., 2006; Nesterenko et al., 2013). Microencapsulation has been used for many industrial applications including food, pharmaceutical, and agricultural areas. Today, there are several reasons to use microencapsulation techniques: protecting sensitive substances from their surroundings, controlled or targeted release of materials, masking of unpleasant tastes and odors, promoting easier handling, and improving processability (solubility, dispersibility, flowability) (Kuang et al., 2010; Nesterenko et al., 2013). The general technique of microencapsulation starts with mixing the core and wall materials to obtain a dispersion, a solution, or an emulsion. The second step involves the actual production of the microcapsules by chemical or mechanical processes. Among the chemical processes are coacervation, complex coacervation, gelation, liposome entrapment, inclusion complexation, interfacial polymerization, and emulsion polymerization. Among the mechanical process are spray drying, spray cooling/chilling, fluidized bed, centrifugal suspension separation, lyophilization, co-crystallization, and extrusion. The choice of appropriate encapsulation technology, carrier material, wall material, and capsule properties is critical in developing a successful commercial application. The selection criteria for a particular process will depend on different factors such as the desired physicochemical properties of the microcapsules (size, charge, yield, encapsulation efficiency); the stability, release, and biological activity of the active material; and process costs. The key point is to select a process that can meet the product specifications at minimum cost, maximum reproducibility, using available facilities, and with high throughput. Process efficiency and product stability can be affected by the selection of the coating material (Davidov-Pardo and McClements, 2014; Fang and Bhandari, 2010; Kuang et al., 2010; Nesterenko et al., 2013). The microcapsule wall usually acts as a barrier, protecting the active material against oxygen, water, light, or contact with other ingredients. It also controls diffusion. Factors such as the efficiency of protection and controlled release of the microencapsulated product mainly depend on the composition and structure of the wall. On the other hand, the nature of the core material must be considered in order to select the most appropriate wall components (Calvo et al., 2012; Carneiro et al., 2013). Bio-based materials such as carbohydrates, fats, waxes, and animal- and plant-derived proteins can be used as a microcapsule coating for food applications. On the other hand, synthetic polymers, such as polyamides, polyurethanes, polyacrylates, phenolic polymers, and polyethylene glycols, are wall materials used in pharmacological and medical applications. In these cases, functionalization of polymeric chains allows one to obtain microparticles with special properties.

358 Chapter 18 Regarding carbohydrates, polysaccharides are chosen as coating components due to their good solubility in water and barrier properties. Some of these components are maltodextrin, starch, gum arabic, chitosan, alginates, and inulin (Fernandes et al., 2014; Nesterenko et al., 2013). Proteins from animal sources (whey proteins, gelatin, casein) and from vegetables (soy proteins, pea proteins, cereal proteins) are also widely used for encapsulation of active substances. These natural polymers offer several advantages: biocompatibility, biodegradability, good amphiphilic and functional properties: such as water, solubility, and emulsifying and foaming capacity. Lipophilic substances such as glycerides, oils, phospholipids, carotenoids, and waxes are also used as carrier materials. They permit the creation of barriers against moisture, and allow for the carrying of hydrophobic substances in aqueous media (Nesterenko et al., 2013). Currently, polyphenols are of great significance in functional foods, and the nutraceutical and pharmaceutical industries. The use of encapsulated polyphenols instead of free compounds can overcome problems of instability and unpleasant tastes or flavors, as well as improve their in vivo and in vitro bioavailability and half-life. Most of the encapsulation technologies employed for other compounds have been used in polyphenol encapsulation. Some technologies are not applied for these compounds, including spray cooling/chilling or spinning disks (Table 18.1). However, this does not necessarily mean that these technologies are not suitable for polyphenol encapsulation. In relation to the wall material employed to microencapsulate polyphenols, maltodextrins, chitosan, starch, alginates, proteins from vegetable and animal sources, and glucans have been chosen to encapsulate polyphenols by spray drying, freeze-drying, and coacervation. Cyclodextrins are usually used to encapsulate polyphenols by molecular inclusion (Fang and Bhandari, 2010).

18.4 GSE Microencapsulation As mentioned above, the incorporation of GSE into food products represents a challenge to food scientists and technologists. Encapsulation by the various techniques described in Section 18.3 can help to overcome the drawbacks and challenges of adding GSE to food products. Self-assembly methods such as liposomes have been successfully used to encapsulate GSE, with encapsulation efficiencies greater than 80%. Coating the liposomes increased their stability and protection, and a synergetic effect was present between the coated liposomes and the GSE. The first stopped the interaction of polyphenols contained in the extracts with the surrounding environment, possibly preventing undesirable interactions when incorporated in food products. The second prevented the oxidation of the phospholipids that form the liposome membrane. As expected due to their intrinsic hydrophobicity, the polyphenolic compounds of the GSE attached to the phospholipidic membrane, rather than residing in the interior of the liposome (Figure 18.3) (Gibis et al.,

Microencapsulation of Grape Seed Extracts 359 Table 18.1: Technologies for encapsulation polyphenols. Reproduced from Fang and Bhandari (2010) with Elsevier license Spray Drying Wall materials

Polyphenols

References

Maltodextrins

Black carrot extracts (anthocyanins) Procyanidins Olive leaf extract Hibiscus sabdariffa L. extract (anthocyanins) Soybean extract Grape seed extract, apple polyphenol Extract and olive leaf extract

Ersus & Yurdagel, 2007

Maltodextrin and gum arabic Chitosan Citris fruit fiber

Colloidal silicon dioxide, maltodextrin and starch Sodium caseinate-soy lecithin

Zhang et al., 2007 Kosaraju et al., 2006 Chiou & Langrish, 2007

Georgetti et al., 2008 Kosaraju et al., 2008

Coacervation Calcium alginate and calcium alginate-chitosan

Yerba mate extract

Gelatin (type A) Glucan

EGCG Black currant extract

Deladino, Anbinder, Navarro, & Martino, 2008 Shutava et al., 2009a; Xiong et al., 2006

Freeze drying Maltodextrin DE20

Anthocyanin

Maltodextrins DE 5-8 and DE18.5 Pullulan

Cloudberry extract Hibisus anthocyanin

Delgado-Vargas et al., 2000 Laine et al., 2008 Gradinaru et al., 2003

Inclusion encapsulation HP-β-CD β-CD and maltosyl-β-CDs β-CD HP-β-CD, maltosyl-β-CDs and β-CDs HP-β-CD α- and β-CDs β-CD HP- β-CD HP- β-CD, maltosyl-β-CDs, β-CDs β-CD α-CD Hydrophobically modified starch Yeast cells

Hesperetin and hesperidin Resveratrol Olive leaf extract (rich in oleuropein) Quercetin and myricetin Kaempferol, quercetin and myricetin 3-hydroxyflavone, morin and quercetin Rutin Curcumin Quercetin and myricetin Rutin Ferulic acid Curcumin Chlorogenic acid

Tommasini et al., 2005 Lucas-Abella´n et al., 2007 Mourtzinos et al., 2007 Lucas-Abella´n et al., 2008 Mercader-Ros et al., 2010 ` et al., 2004 Calabro Ding et al., 2003 Tomren et al., 2007 Lucas-Abella´n et al., 2008 Ding et al., 2003 Anselmi et al., 2008 Yu & Huang, 2010 Shi et al., 2007 (Continued)

360 Chapter 18 Table 18.1: (Continued) Spray Drying Wall materials

Polyphenols

References

Cocrystallization Yerba mate extract

Deladino et al., 2007

Liposome Specific Methods

Polyphenols

References

Thin film evaporation, sonication, reverse phase evaporation, melting, and freezing-thawing Thin film evaporation

Salidroside

Fan et al., 2007

( 1 )-catechin, (-)-epicatechin, EGCG Curcumin Quercetin Resveratrol

Fang, Hwang, Huang, & Fang C.-C, 2006 Takahashi et al., 2009 Priprem et al., 2008 Fan et al., 2007

Using microfluidizer Lipid thin film formation and extrusion Thin film evaporation and sonication

Nanoencapsulation Phase inversion Nanoprecipitation Nanoprecipitation Emulsion-diffusion-evaporation Amphiphilic copolymers Ionotropic gelation Adsorption to prepared nanoparticles (layer-bylayer assembly)

Quercetin and EGCG Curcumin Quercetin Ellagic acid Resveratrol Tea catechins EGCG, tannic acid, curcumin and theaflavin

Barras et al., 2009 Anand et al., 2010 Wu et al., 2008 Bala et al., 2006 Shao et al., 2009 Hu et al., 2008 Shutava et al., 2009b

Emulsions Systems

Polyphenols

Tween 20-BSA- Fe (III)- sunflower oil O/W Caffeic acid emulsion Tween 20-BSA- sunflower oil O/W emulsion Tea extract Tween 20-phosphate buffer-olive oil O/W emulsion Gallic acid, catechin, quercetin

References Almajano et al., 2007 Almajano et al., 2008 Di Mattia et al., 2009

2012). In another work by the same research group it was found that the encapsulation of GSE in liposomes had the same or an adverse effect on the inhibition of the heterocyclic aromatic amines in fried beef patties when compared to the addition of emulsified or bulk GSE (Gibis and Weiss, 2012; Natale et al., 2013). This is a good example illustrating the importance of studying the release of the encapsulated polyphenols in the food matrix and the interactions they may have with microcapsule wall materials and with the food components, rather than simply quantifying the amount of the active material on the assumption that it will have the same functionality in different environmental conditions.

Microencapsulation of Grape Seed Extracts 361

Figure 18.3 Schematic illustration of potential structures of polymer-coated liposomes containing polyphenols: (A) primary liposomes: interaction with phospholipid membrane leads to a binding/integration of the polyphenols in/onto the liposomal membrane; (B) secondary liposomes: after addition of a single layer of chitosan, the Folin Ciocalteu method is still applicable and a reaction occurs; (C) tertiary liposomes: after addition of an additional layer of pectin, the liposomal membrane including the phenolic compounds is now fully coated with polymer, and a further reaction with the Folin Ciocalteu method can no longer occur. Reproduced from Gibis et al. (2012) with permission from the Centre National de la Recherche Scientifique (CNRS) and the Royal Society of Chemistry.

The encapsulation of GSE by spray drying has been widely studied, with positive and promising results. GSE can be simply dispersed together with carbohydrates such as gum arabic or maltodextrin and then spray dried to obtain microcapsules, with encapsulation efficiencies higher than 95% (Zhang et al., 2007). In our research group, we studied and optimized the microencapsulation of GSE by spray drying using zein, mesquite gum, and maltodextrin (Davidov-Pardo et al., 2012a). To ensure the complete dissolution of the GSE, as well as the wall materials, they were dissolved in a hydroethanolic solution. The attraction of the GSE tannins to zein, and the electrostatic attraction between the protein and the mesquite gum, resulted in encapsulation efficiencies higher than 80%, as well as a reduction in the release at different pH levels and simulated gastrointestinal conditions. The encapsulation also protected the GSE from thermal degradation at temperatures up to 180 C. These microcapsules were tested in a bakery product to study the effect of encapsulation on masking the bitterness and astringency of the GSE (Davidov-Pardo et al., 2012b). After the addition of nearly 1% (w/w) of bulk or microencapsulated GSE in cookie dough, the cookies with microencapsulated GSE showed higher anti-oxidant activity than those made with bulk GSE. A QDA® panel found that cookies enriched with GSE presented sensory profiles similar to whole-grain bakery products. Moreover, a consumer hedonic test placed cookies fabricated with microencapsulated GSE in the same score range as the cookies without GSE. A relevant conclusion for the food industry drawn from this study is that the percentage of consumers who are willing to purchase cookies enriched with antioxidants may increase if they receive more information and education on the health benefits of anti-oxidant consumption.

362 Chapter 18 Emulsions can also be used to encapsulate GSE by dispersing them in the oil phase. A study using this technique showed that the addition of the extract did not compromise the characteristics of the emulsion, and these exerted anti-oxidant properties in concentrations of 500 ppm (Hu et al., 2004). The combination of emulsions and spray drying has been widely used over the past few decades (Gharsallaoui et al., 2007). This combination of techniques was used to encapsulate GSE without significant differences in the anti-oxidant activity of the bulk and encapsulated treatments (Kosaraju et al., 2008). The dispersed phase of the emulsions was a mixture of ethanol and lecithin, while the surfactant was sodium caseinate. The emulsions were spray dried in microspheres with a median diameter of 20 μm. GSE has also been encapsulated for pharmaceutical purposes. In topical applications, the encapsulation of GSE was aimed at reducing the browning of extracts over a storage period of 5 months. The microcapsules were fabricated by interfacial cross-linking of grape proanthocyanidins with terephthaloyl, functioning as active and wall material at the same time. The extract incorporated in the microcapsules was stable for the whole storage period at 45 C, with no change in color. It presented a slightly lower anti-oxidant activity than the free extract, and showed a slow degradation and release in plasma (Andry et al., 1998). GSE was also cross-linked with thiolated quaternary ammonium-chitosan conjugates to improve the resistance of endothelial progenitor cells to oxidative stress (Felice et al., 2013). In this case, the particles had sizes slightly above 300 nm and a positive surface charge due to the presence of chitosan in the formulation. The positive charge of the particles improved their cellular uptake and therefore their beneficial effects against oxidative stress. The improvement in cellular uptake using nanoparticles is a promising result for increasing polyphenol bioavailability and bioactivity. As mentioned earlier in Section 18.2, grape seed oil is the other major product derived from grape seeds. It can also be encapsulated, among other reasons to avoid oxidation and rancidity. Oils in general can also be used as carrier materials for other lipophilic compounds through emulsions, solid lipid nanoparticles, or nanostructured lipid carriers (McClements and Rao, 2011). As with any other oil, the most common way to encapsulate it is using different techniques and surfactants to create oil-in-water emulsions (O/W). A mixture design of experiments analyzed by surface response was used to find the optimal concentration of surfactants and biopolymers in the continuous phase to encapsulate grape seed oil by interfacial deposition (Chaparro-Mercado et al., 2012). A combination of low molecular weight surfactants and biopolymers resulted in stable nanoemulsions with droplet sizes of 188 nm and leptokurtic size distribution. Grape seed oil can also be emulsified by low energy methods, for which the main advantages are the simplicity of preparation and the fact that it does not require expensive equipment (Yang et al., 2012). Emulsions with droplet diameters greater than 0.6 μm were created using long chain triglyceride oils such as grape seed oil and phase

Microencapsulation of Grape Seed Extracts 363 inversion as the preparation method (Ostertag et al., 2012). To decrease droplet size and therefore increase the stability of the emulsion, grape seed oil can be combined with low molecular weight oils, such as flavor or mineral oils. O/W emulsions prepared by spontaneous emulsification, with the dispersed phase being grape seed oil and orange oil, proved functional as a delivery system for resveratrol, providing protection against UV-light chemical degradation (Davidov-Pardo and McClements, 2015). This study showed that it is possible to combine different by-products of the wine industry such as grape seed oil and grape skin extract to create a nutraceutical delivery system suitable for enriching a wide variety of food products. A novel approach in the field of encapsulation is to adapt the solution-enhanced dispersion by supercritical fluids (SEDS) technique to encapsulate lipophilic bioactive compounds by antisolvent precipitation. The SEDS technique is usually employed to perform cold extractions of oil or polyphenols from seeds, using carbon dioxide at high pressure as the solvent (Oliveira et al., 2013). If a solution of polymers and active material is injected into the chamber containing the pressurized carbon dioxide, the mixture will precipitate, forming microcapsules (Boschetto et al., 2013). After optimizing the encapsulation conditions, one can obtain microcapsules of grape seed oil with average diameters of less than a micron, and encapsulation efficiencies greater than 60%. It was found that the parameter with the greatest influence on the characteristics of the microcapsules was the temperature of the precipitation chamber. In the future, the SEDS technique could be optimized to perform extractions and encapsulation in a continuous process that will lead to savings in time and resources, and will probably contribute to avoiding damage to the extracts.

18.5 Conclusions and Future Trends Residues of grape processing are an abundant and inexpensive source of polyphenols, GSE being the one with the greatest concentration of polyphenols and anti-oxidant activity compared with other parts of the pomace. The extraction and use of GSE provides an added value to vinification by-products, as well as contributing to the reduction of pollution in wine regions. These extracts can be used in the food industry to replace synthetic antioxidants, synthetic antimicrobials, and/or as functional ingredients in food products or cosmetics. It was shown that GSE can be encapsulated to overcome the drawbacks of its use, using a wide variety of materials and techniques. Encapsulation can be done through chemical or physical methods, and can be aimed at simultaneously tackling more than one of the challenges involved in the use of these extracts. One important parameter that must be taken into account when designing delivery systems to carry GSE in functional foods is to design a system that can load enough GSE to create a beneficial effect, either as a nutraceutical or as a natural additive.

364 Chapter 18 Although there are an increasing number of publications focused on the bioavailability of GSE, it is still important and relevant to increase our knowledge of the mechanisms involved in promoting the bioavailability of GSE and its in vivo action, as well as the impact of the delivery systems. This information will permit the rational design of delivery systems to improve the bioavailability and bioactivity of the extracts. Further research should be also focus on scaling up the microencapsulation processes to analyze their viability in the food industry, and on the selection of certified organic raw materials to encapsulate GSE. These extracts can be used as natural pesticides in organic agriculture or as natural additives in the food industry for the growing organic products market. Finally, only a small portion of the phenolic compounds in the extracts have been identified, most of them remaining uncharacterized, especially polyphenolics of great molecular mass. Due to the complex polyphenolic profile of seed extracts, fractionation and unequivocal identification are needed to offer extracts with controlled characteristics. Further research should also focus on the extraction process of grape by-products for defined final uses (e.g., anti-oxidant or antimicrobial function), once extracted microencapsulation can help to further design the final use of the extracts (e.g., controlled release).

Acknowledgments Dr. Gabriel Davidov-Pardo is recipient of a post-doctoral fellowship by the Secretarı´a de Ciencia Tecnologı´a e Innovacio´n del Distrito Federal (SECITI, Mexico City).

References Andry, M.C., Vezin, H., Dumistracel, I., Bernier, J.L., Le´vy, M.C., 1998. Proanthocyanidin microcapsules: preparation, properties and free radical scavenging activity. Int. J. Pharm. 171, 217 226. Almajano, M.P., Carbo´, R., Delgado, M.E., Gordon, M.H., 2007. Effect of pH on the antimicrobial activity and oxidative stability of oil-in-water emulsions containing caffeic acid. J. Food. Sci. 72, C258 C263. Almajano, M.P., Carbo´, R., Jime´nez, J.A., Gordon, M.H., 2008. Antioxidant and antimicrobial activities of tea infusions. Food. Chem. 108, 55 63. Aron, P.M., Kennedy, J.A., 2008. Flavan-3-ols: nature, occurrence and biological activity. Mol. Nutr. Food Res. 52, 79 104. Anand, P., Nair, H.B., Sung, B., Kunnumakkara, A.B., Yadav, V.R., Tekmal, R.R., et al., 2010. Design of curcumin-loaded PLGA nanoparticles formulation with enhanced cellular uptake, and increased bioactivity in vitro and superior bioavailability in vivo. Biochem. Pharmacol. 79, 330 338. Anselmi, C., Centini, M., Maggiore, M., Gaggelli, N., Andreassi, M., Buonocore, A., et al., 2008. Non-covalent inclusion of ferulic acid with a-cyclodextrin improves photo-stability and delivery: NMR and modeling studies. J. Pharm. Biomed. Anal. 46, 645 652. Badet, C., 2011. Antibacterial activity of grape (Vitis vinifera, Vitis rotundifolia) seeds. Nuts Seeds Health Dis. Prev. 545 552. Bala, I., Bhardwaj, V., Hariharan, S., Kharade, S.V., Roy, N., Ravi Kumar, M.N., 2006. Sustained release nanoparticulate formulation containing antioxidant-ellagic acid as potential prophylaxis system for oral administration as potential prophylaxis system for oral administration. J. Drug. Target. 14, 27 34.

Microencapsulation of Grape Seed Extracts 365 Barras, A., Mezzetti, A., Richard, A., Lazzaroni, S., Roux, S., Melnyk, P., et al., 2009. Formulation and characterization of polyphenol-loaded lipid nanocapsules. Int. J. Pharm. 379, 270 277. Baydar, N.G., Sagdic, O., Ozkan, G., Cetin, S., 2006. Determination of antibacterial effects and total phenolic contents of grape (Vitis vinifera L.) seed extracts. Int. J. Food Sci. Technol. 41, 799 804. Boschetto, D.L., Dalmolin, I., de Cesaro, A.M., Rigo, A.A., Ferreira, S.R.S., Meireles, M.A.A., et al., 2013. Phase behavior and process parameters effect on grape seed extract encapsulation by SEDS technique. Ind. Crops Prod. 50, 352 360. Bucic-Kojic, A., Planinic, M., Tomas, S., Bilic, M., Velic, D., 2007. Study of solid-liquid extraction kinetics of total polyphenols from grape seeds. J. Food Eng. 81, 236 242. Calabro´, M.L., Tommasini, S., Donato, P., Raneri, D., Stancanelli, R., Ficarra, P., et al., 2004. Effects of a- and b-cyclodextrin complexation on the physico-chemical properties and antioxidant activity of some 3hydroxyflavones. J. Pharm. Biomed. Anal. 35, 365 377. Calvo, P., Castan˜o, A.L., Lozano, M., Gonza´lez-Go´mez, D., 2012. Micro-encapsulation of refined olive oil: influence of capsule wall components and the addition of antioxidant additives on the shelf life and chemical alteration. J. Sci. Food Agric. 92, 2689 2695. Carneiro, H.C.F., Tonon, R.V., Grosso, C.R.F., Hubinger, M.D., 2013. Encapsulation efficiency and oxidative stability of flaxseed oil microencapsulated by spray drying using different combinations of wall materials. J. Food Eng. 115, 443 451. Castillo-Mun˜oz, N., Go´mez-Alonso, S., Garcı´a-Romero, E., Hermosı´n-Gutie´rrez, I., 2007. Flavonol profiles of Vitis vinifera red grapes and their single-cultivar wines. J. Agric. Food Chem. 55, 992 1002. Chamorro, S., Gon˜i, I., Viveros, A., Hervert-Herna´ndez, D., Brenes, A., 2011. Changes in polyphenolic content and antioxidant activity after thermal treatments of grape seed extract and grape pomace. Eur. Food Res. Technol. 1 9. Chaparro-Mercado, M.C., Garcia-Ochoa, F., Hernandez-Sanchez, H., Alamilla-Beltran, L., Quintanilla-Carvajal, M.X., Cornejo-Mazon, M., et al., 2012. Design of an interstitial structure for a grape seed oil emulsion by design of experiments and surface response. Rev. Mex. Ing. Quı´m. 11, 11 21. Chedea, V.S., Braicu, C., Chirilˇa, F., Ober, C., Socaciu, C., 2011. Antibacterial action of an aqueous grape seed polyphenolic extract. Afr. J. Biotechnol. 10, 6276 6280. Cheynier, V., 2012. Phenolic compounds: from plants to foods. Phytochem. Rev. 11, 153 177. Chiou, D., Langrish, T.A.G., 2007. Development and characterisation of novel nutraceuticals with spray drying technology. J. Food Eng. 82, 84 91. Chira, K., Suh, J., Saucier, C., Teisse`dre, P., 2008. Les polyphe´nols du raisin. Phytothe´rapie. 6, 75 82. Corrales, M., Han, J.H., Tauscher, B., 2009. Antimicrobial properties of grape seed extracts and their effectiveness after incorporation into pea starch films. Int. J. Food Sci. Technol. 44, 425 433. Curko, N., Ganic, K.K., Gracin, L., Dapic, M., Jourdes, M., Teissedre, P.L., 2014. Characterization of seed and skin polyphenolic extracts of two red grape cultivars grown in Croatia and their sensory perception in a wine model medium. Food Chem. 145, 15 22. Deladino, L., Anbinder, P.S., Navarro, A.S., Martino, M.N., 2007. Co-crystallization of yerba mate extract (Ilex paraguariensis) and mineral salts within a sucrose matrix. J. Food Eng. 80, 573 580. Deladino, L., Anbinder, P.S., Navarro, A.S., Martino, M.N., 2008. Encapsulation of natural antioxidants extracted from Ilex paraguariensis. Carbohydr. Polym. 71, 126 134. Delgado-Vargas, F., Jimenez, A.R., Pardes-Lopez, O., 2000. Natural pigments: carotenoids, anthocyanins and betalainsecharacteristics, biosynthesis, processing and stability. Crit. Rev. Food. Sci. Nutr. 40, 173 289. Di Mattia, C.D., Sacchetti, G., Mastrocola, D., Pittia, P., 2009. Effect of phenolic antioxidants on the dispersion state and chemical stability of olive oil O/W emulsions. Food Res. Int. 42, 1163 1170. Ding, H., Chao, J., Zhang, G., Shuang, S., Pan, J., 2003. Preparation and spectral investigation on inclusion complex of b-cyclodextrin with rutin. Spectrochim. Acta A Mol. Biomol. Spectrosc. 59, 3421 3429. Davidov-Pardo, G., McClements, D.J., 2014. Resveratrol encapsulation: designing delivery systems to overcome solubility, stability and bioavailability issues. Trends Food Sci. Technol. 38, 88 103. Davidov-Pardo, G., McClements, D.J., 2015. Nutraceutical delivery systems: resveratrol encapsulation in grape seed oil nanoemulsions formed by spontaneous emulsification. Food Chem. 167, 205 212.

366 Chapter 18 Davidov-Pardo, G., Arozarena, I., Marı´n-Arroyo, M.R., 2011a. Kinetics of thermal modifications in a grape seed extract. J. Agric. Food Chem. 59, 7211 7217. Davidov-Pardo, G., Arozarena, I., Marı´n-Arroyo, M.R., 2011b. Stability of polyphenolic extracts from grape seeds after thermal treatments. Eur. Food Res. Technol. 232, 211 220. Davidov-Pardo, G., Arozarena, I., Marı´n-Arroyo, M.R., 2012a. Optimization of a wall material formulation to microencapsulate a grape seed extract using a mixture design of experiments. Food Bioprocess Technol. Available from: http://dx.doi.org/10.1007/s11947-11012-10848-z. Davidov-Pardo, G., Moreno, M., Arozarena, I., Marı´n-Arroyo, M.R., Bleibaum, R.N., Bruhn, C.M., 2012b. Sensory and consumer perception of the addition of grape seed extracts in cookies. J. Food Sci. 77, S430 S438. Davidov-Pardo, G., Navarro, M., Arozarena, I., Marı´n-Arroyo, M.R., 2014. Obtaining polyphenolic extracts from wine by-products. In: Caˆmara, J.S. (Ed.), Grapes: Production, Phenolic Composition and Potential Biomedical Effects. Nova Science Publishers, New York, NY, pp. 225 242. Ersus, S., Yurdagel, U., 2007. Microencapsulation of anthocyanin pigments of black carrot (Daucus carota L.) by spray drier. J. Food Eng. 80, 805 812. Fan, M.H., Xu, S.Y., Xia, S.Q., Zhang, X.M., 2007. Effect of different preparation methods on physicochemical properties of salidroside liposomes. J. Agric. Food. Chem. 55, 3089 3095. Fang, J.-Y., Hwang, T.-L., Huang, Y.-L., Fang, C.-L., 2006. Enhancement of the transdermal delivery of catechins by liposomes incorporating anionic surfactants and ethanol. Int. J. Pharm. 310, 131 138. Fang, Z., Bhandari, B., 2010. Encapsulation of polyphenols—a review. Trends Food Sci. Technol. 21, 510 523. Felice, F., Zambito, Y., Belardinelli, E., D’Onofrio, C., Fabiano, A., Balbarini, A., et al., 2013. Delivery of natural polyphenols by polymeric nanoparticles improves the resistance of endothelial progenitor cells to oxidative stress. Eur. J. Pharm. Sci. 50, 393 399. Fernandes, L., Casal, S., Cruz, R., Pereira, J.A., Ramalhosa, E., 2013. Seed oils of ten traditional Portuguese grape varieties with interesting chemical and antioxidant properties. Food Res. Int. 50, 161 166. Fernandes, R.V., Borges, S.V., Botrel, D.A., 2014. Gum arabic/starch/maltodextrin/inulin as wall materials on the microencapsulation of rosemary essential oil. Carbohydr. Polym. 101, 524 532. Georgetti, S.R., Casagrande, R., Souza, C.R.F., Oliveira, W.P., Fonseca, M.J.V., 2008. Spray drying of the soybean extract: effects on chemical properties and antioxidant activity. LWT Food Sci. Technol. 41, 1521 1527. Gharsallaoui, A., Roudaut, G., Chambin, O., Voilley, A., Saurel, R., 2007. Applications of spray-drying in microencapsulation of food ingredients: an overview. Food Res. Int. 40, 1107 1121. Gibis, M., Weiss, J., 2012. Antioxidant capacity and inhibitory effect of grape seed and rosemary extract in marinades on the formation of heterocyclic amines in fried beef patties. Food Chem. 134, 766 774. Gibis, M., Vogt, E., Weiss, J., 2012. Encapsulation of polyphenolic grape seed extract in polymer-coated liposomes. Food Funct. 3, 246 254. Gradinaru, G., Biliaderis, C.G., Kallithraka, S., Kefalas, P., Garcia-Viguera, C., 2003. Thermal stability of Hibiscus sabdariffa L. anthocyanins in solution and in solid state: effects of copigmentation and glass transition. Food. Chem. 83, 423 436. Hollman, P.C.H., Cassidy, A., Comte, B., Heinonen, M., Richelle, M., Richling, E., et al., 2011. The biological relevance of direct antioxidant effects of polyphenols for cardiovascular health in humans is not established. J. Nutr. 141, 989S 1009S. Hu, M., McClements, D.J., Decker, E.A., 2004. Antioxidant activity of a proanthocyanidin-rich extract from grape seed in whey protein isolate stabilized algae oil-in-water emulsions. J. Agric. Food Chem. 52, 5272 5276. Hu, B., Pan, C., Sun, Y., Hou, Z., Ye, Y., Hu, B., et al., 2008. Optimization of fabrication parameters to produce chitosan-tripolyphosphate nanoparticles for delivery of tea catechins. J. Agric. Food. Chem. 56, 7451 7458. Jayaprakasha, G.K., Tamil, S., Sakariah, K.K., 2003. Antibacterial and antioxidant activities of grape (Vitis vinifera) seed extracts. Food Res. Int. 36, 117 122. Kennedy, J.A., Matthews, M.A., Waterhouse, A.L., 2000. Changes in grape seed polyphenols during fruit ripening. Phytochemistry. 55 (1), 77 85.

Microencapsulation of Grape Seed Extracts 367 Kosaraju, S.L., D’ath, L., Lawrence, A., 2006. Preparation and characterisation of chitosan microspheres for antioxidant delivery. Carbohydr. Polym. 64, 163 167. Kammerer, D., Claus, A., Carle, R., Schieber, A., 2004. Polyphenol screening of pomace from red and white grape varieties (Vitis vinifera L.) by HPLC-DAD-MS/MS. J. Agric. Food Chem. 52, 4360 4367. Kosaraju, S.L., Labbett, D., Emin, M., Konczak, I., Lundin, L., 2008. Delivering polyphenols for healthy ageing. Nutr. Diet. 65, S48 S52. Kuang, S.S., Oliveira, J.C., Crean, A.M., 2010. Microencapsulation as a tool for incorporating bioactive ingredients into food. Crit. Rev. Food Sci. Nutr. 50, 951 968. Laine, P., Kylli, P., Heinonen, M., Jouppila, K., 2008. Storage stability of microencapsulated cloudberry (Rubus chamaemorus) phenolics. J. Agric. Food. Chem. 56, 11251 11261. Lafka, T.I., Sinanoglou, V., Lazos, E.S., 2007. On the extraction and antioxidant activity of phenolic compounds from winery wastes. Food Chem. 104, 1206 1214. Lucas-Abella´n, C., Fortea, M.I., Gabaldo´n, J.A., Nu´n˜ez -Delicado, E., 2008. Encapsulation of quercetin and myricetin in cyclodextrins at acidic pH. J. Agric. Food. Chem. 56, 255 259. Lucas-Abella´n, C., Fortea, M.I., Lo´pez-Nicola´s, J.M., Nu´n˜ez-Delicado, E., 2007. Cyclodextrins as resveratrol carrier system. Food. Chem. 104, 39 44. Lutterodt, H., Slavin, M., Whent, M., Turner, E., Yu, L., 2011. Fatty acid composition, oxidative stability, antioxidant and antiproliferative properties of selected cold-pressed grape seed oils and flours. Food Chem. 128, 391 399. Madene, A., Jacquot, M., Scher, J., Desobry, S., 2006. Flavour encapsulation and controlled release—a review. Int. J. Food Sci. Technol. 41, 1 21. Makris, D.P., Boskou, G., Andrikopoulos, N.K., 2007. Recovery of antioxidant phenolics from white vinification solid by-products employing water/ethanol mixtures. Bioresour. Technol. 98, 2963 2967. Matthaeus, B., 2008. Virgin grape seed oil: is it really a nutritional highlight? Eur. J. Lipid Sci. Technol. 110, 645 650. McClements, D.J., 2012. Requirements for food ingredient and nutraceutical delivery systems. In: Encapsulation Technologies and Delivery Systems for Food Ingredients and Nutraceuticals, Woodhead Publishing, UK, pp. 3 18. McClements, D.J., Rao, J., 2011. Food-grade nanoemulsions: formulation, fabrication, properties, performance, biological fate, and potential toxicity. Crit. Rev. Food Sci. Nutr. 51, 285 330. McRae, J.M., Kennedy, J.A., 2011. Wine and grape tannin interactions with salivary proteins and their impact on astringency: a review of current research. Molecules. 16, 2348 2364. Mendoza, L., Yan˜ez, K., Vivanco, M., Melo, R., Cotoras, M., 2013. Characterization of extracts from winery by-products with antifungal activity against Botrytis cinerea. Ind. Crops Prod. 43, 360 364. Mercader-Ros, M.T., Lucas-Abella´n, C., Fortea, M.I., Gabaldo´n, J.A., Nu´n˜ez-Delicado, E., 2010. Effect of HPb-cyclodextrins complexation on the antioxidant activity of flavonols. Food. Chem. 118, 769 773. Monagas, M., Gomez-Cordoves, C., Bartolome, B., Laureano, O., Ricardo-Da-Silva, J.M., 2003. Monomeric, oligomeric, and polymeric flavan-3-ol composition of wines and grapes from Vitis vinifera L. cv. Graciano, Tempranillo, and Cabernet Sauvignon. J. Agric. Food Chem. 51, 6475 6481. Mourtzinos, I., Salta, F., Yannakopoulou, K., Chiou, A., Karathanos, V.T., 2007. Encapsulation of olive leaf extract in becyclodextrin. J. Agric. Food. Chem. 55, 8088 8094. Natale, D., Gibis, M., Rodriguez-Estrada, M.T., Weiss, J., 2013. Inhibitory effect of liposomal solutions of grape seed extract on the formation of heterocyclic aromatic amines. J. Agric. Food Chem. 62, 279 287. Nesterenko, A., Alric, I., Silvestre, F., Durrieu, V., 2013. Vegetable proteins in microencapsulation: a review of recent interventions and their effectiveness. Ind. Crops Prod. 42, 469 479. Oliveira, D.A., Salvador, A.A., Smaˆnia Jr., A., Smaˆnia, E.F.A., Maraschin, M., Ferreira, S.R.S., 2013. Antimicrobial activity and composition profile of grape (Vitis vinifera) pomace extracts obtained by supercritical fluids. J. Biotechnol. 164, 423 432. Ostertag, F., Weiss, J., McClements, D.J., 2012. Low-energy formation of edible nanoemulsions: factors influencing droplet size produced by emulsion phase inversion. J. Colloid Interface Sci. 388, 95 102.

368 Chapter 18 Ou, K., Gu, L., 2014. Absorption and metabolism of proanthocyanidins. J. Funct. Foods. 7, 43 53. Pinelo, M., Rubilar, M., Jerez, M., Sineiro, J., Nunez, M.J., 2005. Effect of solvent, temperature, and solvent-tosolid ratio on the total phenolic content and antiradical activity of extracts from different components of grape pomace. J. Agric. Food Chem. 53, 2111 2117. Priprem, A., Watanatorn, J., Sutthiparinyanont, S., Phachonpai, W., Muchimapura, S., 2008. Anxiety and cognitive effects of quercetin liposomes in rats. Nanomedicine. 4, 70 78. Rao, P.U., 1994. Nutrient composition of some less-familiar oil seeds. Food Chem. 50, 379 382. Rombaut, N., Savoire, R., Thomasset, B., Belliard, T., Castello, J., Van Hecke, E., et al., 2014. Grape seed oil extraction: interest of supercritical fluid extraction and gas-assisted mechanical extraction for enhancing polyphenol co-extraction in oil. C. R. Chim. 17, 284 292. Ross, C.F., Hoye Jr, C., Fernandez-Plotka, V.C., 2011. Influence of heating on the polyphenolic content and antioxidant activity of grape seed flour. J. Food Sci. 76, C884 C890. Shao, J., Li, X., Lu, X., Jiang, C., Hu, Y., Li, Q., et al., 2009. Enhanced growth inhibition effect of resveratrol incorporated into biodegradable nanoparticles against glioma cells is mediated by the induction of intracellular reactive oxygen species levels. Colloids Surf B Biointerfaces. 72, 40 47. Shi, G., Rao, L., Yu, H., Xiang, H., Pen, G., Long, S., et al., 2007. Yeastcell-based microencapsulation of chlorogenic acid as a water-soluble antioxidant. J. Food Eng. 80, 1060 1067. Shi, J., Yu, J., Pohorly, J.E., Kakuda, Y., 2003. Polyphenolics in grape seeds: biochemistry and functionality. J. Med. Food. 6, 291 299. Shutava, T.G., Balkundi, S.S., Lvov, Y.M., 2009a. -Epigallocatechin gallate/gelatin layer-by-layer assembled films and microcapsules. J. Colloid. Interface. Sci. 330, 276 283. Shutava, T.G., Balkundi, S.S., Vangala, P., Steffan, J.J., Bigelow, R.L., Cardelli, J.A., et al., 2009b. Layer-bylayer-coated gelatin nanoparticles as a vehicle for delivery of natural polyphenols. ACS Nano. 3, 1877 1885. Takahashi, M., Uechi, S., Takara, K., Asikin, Y., Wada, K., 2009. Evaluation of an oral carrier system in rats: bioavailability and antioxidant properties of liposome-capsulated curcumin. J. Agric. Food. Chem. 57, 9141 9146. Tommasini, S., Calabro´, M.L., Stancanelli, R., Donato, P., Costa, C., Catania, S., et al., 2005. The inclusion complexes of hesperetin and its 7-rhamnoglucoside with (2-hydroxypropyl)-β-cyclodextrin. J. Pharm. Biomed. Anal. 39, 572 580. Tomren, M.A., Masson, M., Loftsson, T., Tonnesen, H.H., 2007. Studies on curcumin and curcuminoids XXXI. Symmetric and asymmetric curcuminoids: stability, activity and complexation with cyclodextrin. Int. J. Pharm. 338, 27 34. ˇ ˇ 2009. Extraction of phenolic compounds from elder berry and different grape Vatai, T., Skerget, M., Knez, Z., marc varieties using organic solvents and/or supercritical carbon dioxide. J. Food Eng. 90, 246 254. Vidal, S., Francis, L., Guyot, S., Marnet, N., Kwiatkowski, M., Gawel, R., et al., 2003. The mouth-feel properties of grape and apple proanthocyanidins in a wine-like medium. J. Sci. Food Agric. 83, 564 573. Wu, T.-H., Yen, F.-L., Lin, L.-T., Tsai, T.-R., Lin, C.-C., Cham, T.-M., 2008. Preparation, physicochemical characterization, and antioxidant effects of quercetin nanoparticles. Int. J. Pharm. 346, 160 168. Xiong, S., Melton, L.D., Easteal, A., Siew, D., 2006. Stability and antioxidant activity of black currant anthocyanins in solution and encapsulated in glucan gel. J. Agric. Food. Chem. 54, 6201 6208. Yu, H., Huang, Q., 2010. Enhanced in vitro anti-cancer activity of curcumin encapsulated in hydrophobically modified starch. Food. Chem. 119, 669 674. Yang, Y., Marshall-Breton, C., Leser, M.E., Sher, A.A., McClements, D.J., 2012. Fabrication of ultrafine edible emulsions: comparison of high-energy and low-energy homogenization methods. Food Hydrocolloids. 29, 398 406. Yu, J., Ahmedna, M., 2013. Functional components of grape pomace: their composition, biological properties and potential applications. Int. J. Food Sci. Technol. 48, 221 237. Zhang, L., Mou, D., Du, Y., 2007. Procyanidins: extraction and micro-encapsulation. J. Sci. Food Agric. 87, 2192 2197.