Lecithin chocolate, production

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%. 

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. 

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. 

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). 

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. 

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. 

Lecithins are used in a great variety of processed foods such as bread, cakes and biscuits, chocolate, sugar confectionery products, cocoa powder, coffee whiteners, dried milk products and baby foods. 

Morlock, G., Kruger, S., Burmann, L., and Lochnit, G. Jnly 2-4, 2014, HPTLC-FLD-ESI-MS and HPTLC-MALDI-TOF/TOF MS analysis of lecithins nsed in the production of chocolate, HPTLC 2014, Lyon, France, abstract P-8. 

A phospholipid has a polar head and a long, nonpolar tail. Phospholipids are found in all animal and vegetable cells, where they are part of cell membranes (Fig. 22.15). The phospholipid shown above is commonly called a lecithin. It is used widely in the cosmetic and food industries as an emulsifier, a substance that holds two immiscible liquids together as a suspension. You ll find lecithins in many food products such as chocolate, ice cream, and margarine. 

Together with lecithin, PGPR is used in the production of chocolate. It completely eliminates the flow point of a molten chocolate mass, but hardly lowers the viscosity. 

Emulsifiers, Stabilizers, and Thickeners. A wide variety of products are used to improve texture. For example, lecithin, obtained primarly from soybeans is used as an emulsifier in dressings and chocolates, to keep ingredients in a processed form from separating. Pectin and gelatin are added to thicken jams and jellies and gums, dextrins, and starches are used to give more substance to soups and desserts. 

The commercial source of lecithin is predominately soybeans. It is an FDA approved food additive employed as a stabilizer and emulsifier in margarine, dressings, chocolate, frozen desserts, and baked goods. Furthermore, lecithin is also used in such products as paints, soaps, printing inks, and cosmetics, to name only a few. 

Processed phospholipids ( special lecithins ) are used in the manufacturing of paints, leather, and numerous foods such as bakery goods, chocolate, margarines, etc. Derivatized phospholipids also have specific applications in pharmaceuticals and personal care products [60]. Although several chemical and physical modifications of lecithins have been adopted by industry [61], there is a clear scope for the application of enzymes to the transformation of... 

Two major natural surfactants being used include lecithin, an emulsifier used in chocolate and ice cream manufacture, and plant saponins. However, the use of saponins has some limitations. First of all, these compounds are not as potent surfactants as the synthetic ones, and, second, the supply from plant sources has been quite limited, which makes these products less available and rather expensive. 

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