Physicochemical and histological foundations of soy whey-based fermentation in processing karakul skins

The article investigates the possibility of using soy whey as an alternative to traditional cereal-flour fermentation methods in the processing of karakul fur skins. First, the main physicochemical properties of soy whey obtained from a local manufacturer were determined, and its carbohydrate composition was analyzed by high-performance liquid chromatography (HPLC). The study showed that, in addition to fructose, glucose, sucrose, and maltose, soy whey contains oligosaccharides such as raffinose and stachyose, which indicates its high nutritional value for fermentation processes. Karakul skins fermented in barley groats, as well as in a mixture of soy whey and partially barley groats, were then tanned and finished, and compared histologically. Microphotographs obtained with a LEICA-1000 DM microscope demonstrated that the dermal structure, the orderly separation of collagen fibers, hair follicles, stroma, and hypodermis, is preserved. Fermentation based on soy whey selectively reduces interfibrillar material in the dermis, making the flesh soft and plastic, without damaging the fur side, pigmentation, or the mechanical stability of the follicles. The results confirm that soy whey can be used as a resource-saving and exobiologically acceptable technology in the processing of karakul skins.