Chocolate
From the foregoing, it should be clear that the action of lecithin is purely a surface, and therefore it is important that the solid particles on the surface of chocolate was activated maximum amount of added lecithin.
The amount of lecithin, which is effective in chocolate, is rather limited and amounts to 0,2-0,6% for soy and other vegetable lecithins and up to 1% for synthetic phospholipid ULH. In the first case, the figures refer to natural lecithins for industrial use. Soy products contain usually from 65% to 70% of active phospholipids. The residue is a vegetable oil according to the origin of the product, and it can be replaced with cocoa butter or refined vegetable oil. In countries where the addition of lecithin is limited by regulatory enactments, the content of active fosfolipids is sometimes determined. In other countries, the use of lecithin substitutes is still prohibited.
Controlling the viscosity of chocolate is a complex procedure, and simply adding, for example, 0,5% lecithin along with other ingredients, does not provide the maximum viscosity reduction. In practice, lecithin is added in the main * for preserving the cocoa butter throughout the whole process, and therefore sometimes it is necessary to distribute its application between the stages of grinding and conciliation. To obtain the maximum viscosity reduction, lecithin should be added as close as possible to the end of the conching, which is associated with the need to retain lecithin on the surface of the particles. Too dry or too liquid mixture will not flow to the grinding roll at the optimum speed, which will result in the formation of an uneven film on them. If the purified mass can be brought into a proper physical state with a low content of cocoa butter, the saving effect of this oil will be noticeable throughout the entire process.
Thus, if the total lecithin additive is 0,5%, it is advisable to add 0,15-0,2% at the mixing stage before grinding, and the rest at the end of conching. If at the grinding stage chocolate mass without lecithin; has a cocoa butter content, for example, 27% (to ensure passage through the rolls), then adding lecithin has the same consistency when the content of cocoa butter on 1-2% is less. The actual content of cocoa butter depends on1 Formulation and particle size, but a reduced content of cocoa butter at dobavlennі lecithin affect and its content in the finished chocolate.
The next step is to remove the "flake" from the grinding rollers and their conversion into the moving mass, suitable for conching without further addition of lecithin. This is achieved by mechanically mixing and stirring - whether in a separate mixer or first stage of operation or continuous rotary konshmashiny. This part of the technology called "dry conching" (see., "Production of chocolate"), followed by stirring at a higher speed and (in some cases) adding cocoa butter.
At the end of the conching the lecithin residue was added along with flavoring agents, and after a sufficient time to disperse, check viscosity. If necessary, it is adjusted by adding cocoa butter. In no event should not adjust the viscosity by adding lecithin.
Sometimes it is possible to achieve a further reduction of viscosity using rapid mixing after conching, but this depends on the type of chocolate, the cocoa butter content. The extent of this reduction can only be set empirically.
Cocoa powder and chocolate drinks
Micronized powders, in particular fat-containing (cocoa powder for chocolate powder beverage preparation) is difficult wetted and dispersed in water or in vodosodeozhaschih fluids - such as milk.
Use as a surfactant lecithin or modified lecithin causes changes in the physical structure of the powder, whereby the dispersion occurs.
The addition of lecithin is often combined with the instantization process (see Milk Powder). This allows fine particles to be “adhered” into agglomerates with capillary channels through which liquid seeps, causing a wetting effect. Such agglomerates also affect the density of the material, and therefore, for a given mass, it has a greater volume.
Modified lecithins currently produced specifically for the production of wettable powders and their use in liquid form by spraying at normal temperatures special mixers for powders and sprayers or during spray drying. If the powder has already been agglomerated, modified lecithin can be added in dry powder by simple mixing.
Literature
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