The quality of a fermented milk-containing product with a combined fat composition
Authors: Andreus S. , Romanchuk I. , Rudakova T. , Moiseeva L. , Narizhnyy S. 
Published: January 2024

Wholesome and healthy nutrition is one of the most important and necessary conditions for maintaining human life and health. Proper nutrition ensures the harmonious development of children, contributes to the prevention of diseases, increases work capacity, prolongs people's lives and creates conditions for adaptation to the environment, etc. But recently, the state of health of the population is characterized by negative trends. Therefore, the creation of high-quality fermented milk products with a combined fat composition is necessary and relevant. The purpose of the work was to study the quality of a milk-containing fermented product with a combined composition of raw materials and establish a guaranteed shelf life based on the assessment of its quality indicators. The article presents the study of qualitative assessment of the quality of milk-containing fermented products with a combined fat composition and the study of their organoleptic, physicochemical, and microbiological indicators during storage. A hierarchical structure of a complex indicator of product quality is provided, in which significant parameters are defined - these are microbiological indicators (the number of lactic acid bacteria, yeast, mold); organoleptic indicators (taste, aroma, consistency); physical and chemical indicators (viscosity, titrated acidity, peroxide value). A complex index of product quality was calculated using the complex equations and it was established that the experimental samples had the highest indicators. Studies of the organoleptic parameters of the samples of the fermented product during storage showed that no significant changes in the controlled parameters were detected during 21 days. Compaction of the structure of the products without whey separation was noted, their appearance remained acceptable, and the taste was pure sour milk without extraneous aftertaste and smell. The content of soluble protein in experimental subjects slowly increased over 14 days and amounted to 75-82 μg. Values of peroxide number after 14 days in experimental samples of the product increased by almost 2 times compared to freshly prepared samples of the product. An increase in viscosity was noted in the range of 7-10% in test samples of the fermented product with leavening agent for yogurt, above 10% in test samples of the fermented product with leavening agent for sour cream. In addition, an increase in titrated indicators within 72-90 oT and the number of lactic acid bacteria from 1.4·108 CFU/cm³ to 2.3·108 CFU/cm³ was recorded, depending on the leavening preparation. Based on the qualitative assessment, the quality of the fermented milk-containing product with the combined composition of raw materials is determined. As a result of studies of quality indicators, a guaranteed shelf life of a fermented milk-containing product with a combined composition of raw materials was established for 14 days.
Key words: fermented milk-containing product, combined composition, quality, organoleptic indicators, physicochemical indicators, microbiological indicators, shelf life.