Industrial chocolate manufacturers use soy lecithin because it improves the processing of Chocolate, especially its flowability. This means that it makes the Chocolate thinner, so to speak, and it thus flows better and spreads in the corners of the molds. It also prevents the pipes from sticking in industrial production. It also prevents problems in production that occur when there is moisture. It is also cheaper than cocoa butter and helps sugar crystallization, thus increasing shelf life of Chocolate.
Soy lecithin, however, changes the texture and flavor of the Chocolate. It makes the Chocolate slightly waxy, which causes the Chocolate to lose creaminess. In addition, soy lecithin tends to flatten the subtle flavors in cocoa and eleminate the delicate ones.
Chocolatiers who handcraft their Chocolate naturally place special emphasis on the subtle flavors and therefore do not use soy lecithin, among other things.
Although soy lecithin occurs naturally in soybeans, it is an industrially obtained product. Soy lecithin is extracted with chem. Solvents such as acetone are used to extract it and it is also bleached to turn the dirty brown color into a light yellow like cocoa butter. In addition, soy is rarely sustainably grown and much of it comes from genetically modified plants.