. Both Russia and South Africa have a long-standing history of fermented milk product consumption. Along with the products widely distributed around the world, such as yoghurts, in each of these countries there are a number of national products. An example of a widely demanded fermented milk product in Russia is Kefir.This productis used not only as a food source in the diet of children and adults, but also in medical institutions, since ithasa positive effect onhuman health when consumed regularly. South Africa is characterized by the consumption of products such as Amasi,which is produced commercially. Its consumption has also been shown to have beneficial effects on the digestive system. In this research, the metabolic profiles(fatty acid composition and volatile compounds) of these fermented milk products were analyzed and these showed significant differences. The results indicated that this metabolite composition reflected the different production protocols and microbial complexity of these dairy products. The functional properties of the studied drinks were also considered.The average content of L-leucine equivalents in Amasi was slightly higher (6.5-8.9mMol×L −1) than in Kefir (4.9-6.7mMol×L −1). Antioxidant and antihypertensive activity of the fermented products correlated with the depth of hydrolysis of the milk proteins. Amasishowed higher antioxidant and antihypertensive activities (600- 796µМolТE/ml and 1.3-1.5mg/ml, respectively) than Kefir (246-574µМolТE/ml and 2.0-4.3mg/ml, respectively).
Keywords: fermented products, Kefir, Amasi,metabolic profile, antioxidant potential, antihypertensive properties
Structural and functional properties of milk proteins as affected by heating, high pressure, Gamma and ultraviolet irradiation: a review
