DEVELOPMENT OF TECHNOLOGY OF YOGHURT BY USING ACID WHEY

Abstract

Fermented milk products play an important role in people's nutrition, especially for children, the elderly, and the ill people. The dietary properties of fermented milk products are that they improve metabolism, stimulate the secretion of stomach acid, and stimulate the appetite. The presence of microorganisms in their composition that can survive in the intestines and inhibit putrefactive microflora leads to inhibition of putrefaction processes and the extinction of the formation of toxic protein breakdown products entering the human blood. Among dairy products, dietary fermented milk products are in high demand, especially dietary yogurts with vegetable additives. Whey is the liquid protein part of milk that remains after the separation of cottage cheese obtained as a result of milk coagulation by acidic or proteolytic enzymes. It has high nutritional and biological value. Even though that the composition of the whey is a valuable secondary product, the question of its rational use is still unresolved. The purpose of this research is to develop an optimal technology for the production of fermented milk products, namely yogurt by using acid whey. For this study, acid whey was selected, since the amount of produced acid whey more than the production of the amount of cheese whey. Recently, there has also been a growing interest in the possibility of using whey proteins in the development of technology for fermented milk products, but more and more often in these studies, a cheese whey is used. According to GOST 34352-2017 "Milk whey-raw materials" in terms of physical and chemical composition acid whey is not inferior to cheese whey, except for the indicator of titrated acidity, which is much higher in acid whey. Therefore, the use of acid whey in the development of technology for the production of fermented milk products is a time-consuming process that requires careful selection of the primary processing of whey and strict compliance with the processing modes of the main product. For the fermentation process of yogurt with the addition of whey of different origins, several types of starter cultures were selected, such as starter cultures from Genesis, Vivo, and Yalactis company. To obtain a dense, homogeneous clot of the finished product and to reduce the use of heat treatment, ultrasonic (US) treatment was used before the fermentation process of the mixture, and instead of traditional homogenization and pasteurization processes. And also to intensify the fermentation process of microorganisms by saturating them with oxygen at the beginning of the fermentation process, the samples were rotated around their axis in a shaker incubator for a certain amount of time at a constant fermentation temperature. The study was based on organoleptic and physicochemical analysis of prepared yoghurt with added whey, as well as a comparative analysis of production technology and physicochemical characteristics of yoghurt added natural whey and whey, produced from the manufacture of cottage cheese from powdered milk. We also studied the optimal ratio of milk and whey to obtain more suitable and attractive for customer organoleptic properties.