Chocolate lecithin

Lecithin. Lecithin [8002-43-5] (qv) is a mixture of fat-like compounds that includes phosphatidyl choline, phosphatidyl ethanolamines, inositol phosphatides, and other compounds (37). Commercial lecithin was originally obtained from egg yolks, but is now extracted from soybean oil. Lecithin is used in many products, including margarine, chocolate, ice cream, cake batter, and bread. 

The worldwide uses of lecithin break down as follows margarine, 25—30% baking/chocolate and ice cream, 25—30% technical products, 10—20% cosmetics, 3—5% and pharmaceuticals, 3%. 

Chocolate (0.3—0.5% lecithin) lecithin is a wetting agent and emulsifier. It facihtates mixing, saves processiag time and power, saves cocoa butter, stabilizes viscosity, iacreases shelf life, counteracts moisture thickening, and aids release of molded goods (see Chocolate and cocoa). 

Lecithin (qv), a natural phosphoHpid possessing both hydrophilic and hydrophobic properties, is the most common emulsifier in the chocolate industry (5). The hydrophilic groups of the lecithin molecules attach themselves to the water, sugar, and cocoa soflds present in chocolate. The hydrophobic groups attach themselves to the cocoa butter and other fats such as milk fat. This reduces both the surface tension, between cocoa butter and the other materials present, and the viscosity. Less cocoa butter is then needed to adjust the final viscosity of the chocolate. 

The amount of lecithin required falls within a narrow range of about 0.2—0.6% (27). It can have a substantial effect on the amount of cocoa butter used, reducing the final fat content of chocolate by as much as 5%. Because cocoa butter is usually the most costly ingredient in the formulation of chocolate, the savings to a large manufacturer can be substantial. 

The huge variety of emulsions used as food, medicinal, cosmetic, and other industrial products make these colloids important practical systems in which the surface monolayers exert considerable influence. We have already discussed the use of lecithin to control the viscosity and the texture of chocolate in Vignette IV in Chapter 4. 

W van Nieuwenhuyzen. Chocolates need tailor-made lecithins. Food Tech Int Europe 35-37, 1996. 

Campanellae al. [92] Lecithin Soya seed flour, soya seed oil, ground soya seed oil, ground maize germ oil, milk chocolate, soya lecithin in gel capsules, soya lecithin in tablets Phospholipase D and choline oxidase/both immobilised in kappa-carrageenan gel or in dialysis membrane Amperometric gas diffusion electrode for oxygen ... 

Two of the earliest edible applications of lecithin, viscosity reduction in chocolate and confectionery products, and emulsification/antispatter properties in margarine, still enjoy wide popularity and represent outlets for large volumes of lecithin products. In addition, other early uses such as in bakery goods, pasta, textiles, insecticides, and paints, among others, are still active today. 

Commercial lecithin products that were sold many decades ago for applications such as chocolate and confectionery products, margarine, bakery goods, pasta products, textiles, insecticides, and paints are still active today because of their emulsifying, wetting, colloidal, antioxidant, and physiological properties. Lecithin s multifunctional properties and its natural status make it an ideal food ingredient. The major applications and functional properties of lecithin products are shown in Table 25 (7). 

Solid particle dispersions (Sols). Many lecithin products are still the best and most effective surfactants for dispersing sols. This seems to be because of lecithin s affinity for solids—liquid surface interfaces. Phospholipids seem particularly attracted to particles containing metals and metal salts. Examples of food sols include some liquid chocolates, instant drinks, frosting mixes, pigmented foods, and others. The nonfood applications include paints, inks, and other pigmented coatings. 

Manufacturing techniques employed in producing instant products include spray-coating dry powders with fluid lecithin products, cospray drying powders with more hydrophihc lecithins such as the oil-free forms, or hydroxylated lecithin, and agglomeration of the powder with an aqueous dispersion of a hydrophihc lecithin. Some types of powders, for example, starches, gums, and chocolate drink mixes, require agglomeration with an aqueous dispersion of lecithin to achieve optimum wettabihty and dispersibility. 

Confections. There are three major specific properties for lecithin in confections emulsification (e.g., caramels), anti-stick/release properties, and viscosity modification (e.g., chocolate) (175). None of these properties stand alone. For example, emulsification in caramels will influence shelf life and texture. In chocolate, viscosity modification will alter production costs and texture of the finished product. 

Studies by Sinram and Schmitt (176) have shown significant improvements in dark and milk chocolates using a fractionated, phosphatidylcholine-enriched soy lecithin as compared with a standard soy lecithin or no lecithin at all. The effect... 

In chocolate coating, the liquid phase is an oil (cocoa butter). The addition of lecithin aids the wetting of solid cocoa particles by this oil, most probably by lowering This lowers the viscosity of the heterogenous mass as well as giving a smoother mouthfeel to the final product. 

The confectionery industry utilizes the emulsification, antistick, and viscosity properties of lecithin and benefits from the concurrent effects of shelf-life extension, texture improvement, and decreased production costs (83). A product such as caramel will not blend correctly in the absence of lecithin. Uniform dispersion of fat, aided by lecithin, will decrease stickiness and provide tenderness for ease of cutting. The natural antioxidant properties of lecithin slow the decay of any product in which it is incorporated. Viscosity is very important in the chocolate industry where shape is often a requirement for consumer acceptability. High concentrations of butter, such as cocoa butter, impart high viscosity, which in turn makes... 

Some oil-soluble emulsifiers affect the crystallization process and development of polymorphic forms of fats (4-8). Sucrose fatty acid ester or sucrose polyesters (SPE) and lecithins are well-known food emulsifiers (9,10). The main characteristics of lecithins and SPE useful in food applications are their oil-in-water and water-in-oil emulsifying properties, that result in dispersion with condensed milk and coffee whitener, and prevention of blooming in candy products and chocolate (7,9-11). But there are very few reports about two effects of SPE on the crystallization of fats and oils, i.e., enhancement and inhibition (12,13). 

The fine ground chocolate powder or paste is conveyed into refining equipment where the rest of the cocoa butter, emulsifying agent (lecithin) and the flavourings are added. 

Alcohol fractionation of deoiled lecithin provides alcohol-soluble and alcohol-insoluble fractions enriched with PC and PI respectively. The PC-enriched fraction is an excellent oil-in-water emulsifier. The Pi-enriched fraction is a good water-in-oil emulsifier often used in the chocolate industry to increase the viscosity of the mass, therefore reducing the need for cocoa butter. The typical composition of these lecithin products is shown in Table 2.11. 

Chocothin. [Lucas Meyer] Lecithin vise, reducing agent ftv milk chocolates. 

Chocotop. [Lucas Meyer] Fractioiiated soya lecithins natural vise, reducing agents esp. for chocolate mfg. 

Smooth texture If the chocolate contains too little cocoa butter between the particles, the chocolate will be too thick to flow Into a mold. To Improve the flow of the chocolate without increasing particle size, manufacturers can either add more fat to the mixture or add an emulsifier, such as lecithin. Lecithin is a fat often obtained from soybeans that helps keep the fat molecules evenly suspended, or emulsified. In the chocolate. 

Chocolate and couvertures are dispersions of small (10-25 im) particles of sugar, and, depending on the type of chocolate, cocoa powder solids and non-fat milk solids, in a continuous fat phase. A layer of emulsifier (usually lecithin) is strongly adsorbed to the surface of the sugar particles. Chocolates and couvertures for ice cream products generally have higher fat contents (40-60%) than their normal ambient counterparts (28-35%). This is because chocolate on ice cream products is eaten at lower temperatures than ambient chocolate. An ambient chocolate would be very hard at —18 °C, and would have a waxy texture when eaten in conjunction with ice cream, because the mouth would be too cold to melt the fat in the chocolate. 

Depending on the food matrix, multiplex DNA can show some discrepancies in the detection of different allergenic targets, due to differential efficiency of the amplification process. This issue has been shown in the case of the determination of the hazelnut allergen isoforms Cor a 1.03 and Cor a 1.04 in some matrices, including dark chocolate, soy milk, lecithin supplement, and snack muesli (Bettazzi et al., 2008). For this reason, multiplex assays must be evaluated carefully during and after development, to reduce inconsistent results. 

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