Selection of starter cultures for kefir product with reduced allergenicity

The biocatalitic conversion of milk protein providing obtaining of hydrolysates with predetermined molecular-mass distribution is considered to be the most promising approach to reduction of milk products allergenicity. Possibility to apply hydrolysate of cheese whey proteins received after concentration of whey in the ultra-filtration plant in the technology of fermented milks was studied. Experimental study of the dynamics of coagulation of the normalized mixtures with different cultures of the lactic acid bacteria was carried out with the aim to select starters' microorganisms for production of the kefir product with reduced allergenicity. The results of the research allowed substantiate selection of the starter cultures F-DVS-XPL-1/20x500U and the yeast SWING LAF/10U that makes it possible to reduce fermentation time to 8-9 hours due to the intensive fermentation of lactose by lactococci and thermophilic streptococcus. Presence of Leuconostoc mesenteroides ssp. cremoris in the composition of starter microflora promotes formation of viscous coagulum and gives pure lactic acid aroma. Addition of the 0.3 % of the starter cultures to the normalized mixture provides better organoleptic characteristics of the product. Clinical trials of the finish product confirmed its residual antigenicity 0.037 % in relation to the concentration of beta-lactoglobulin in cow milk as well as its safety and functionality. According to the conclusion of the Research Institute of Nutrition of the Russian Academy of Medical Sciences the kefir product received the status of the dietetic (preventive) food product for adult people with signs of food allergy to milk proteins.

whey protein hydrolysate, kefir product, starter microorganisms, yeast, residual antigenicity