The main problem: Modern research in the development of fermented milk products is focused on increasing the bioavailability of milk components, as well as the use of bacterial components of sourdough, which increase health properties. The use of the fermentation process of skimmed milk with a combined starter consisting of traditional for cottage cheese and starter cultures of probiotic cultures immobilized in a gel of biopolymers is very important. Purpose: The purpose of this study is to determine the optimal amount of starter, consisting of an association of probiotic cultures immobilized in a gel of biopolymers (membranes) to be added to fermented skimmed milk in order to enrich it with functional ingredients. Methods: A one-factor experiment was used. The culture association Propionibacterium freudenreichii subsp. was used as a regulatory factor. Shermanii, Bifidobacterium lactis and Streptococcus thermophilus, immobilized in a biopolymer gel, added to skimmed milk in the form of membranes (determined as a percentage of the mass of fermented milk). Controlled factors are the main indicators characterizing the efficiency of the skim milk fermentation process; these are active acidity, the logarithm of the number of viable cells of bifidobacteria, the logarithm of the number of viable cells of propionic acid bacteria, and organoleptic evaluation. Results and their significance: Based on the results of a mathematical analysis of the totality of values of controlled factors depending on the amount of starter cultures of probiotic cultures, mathematical models were built to determine the degree of influence of the starter on the quality indicators of the product, using the Table Curve 3D-v4 mathematical computer program.

Main problem: the development of a new direction in the food industry – the so-called functional nutrition, which means the use of such products of natural origin, which, when systematically used, have a regulatory effect on the body as a whole or on its specific systems and organs, has been widely recognized all over the world: immunostimulants, biocorrectors for blood pressure, cholesterol levels, etc. When creating functional dairy products, ingredients of plant origin are increasingly included in recipes, which are sources of dietary fiber, vitamins and microelements, organic acids and other biologically active compounds, which can also serve as flavor fillers. Purpose: to develop a technology for the preparation of a fermented milk product with the addition of an extract from gourds. To do this, it was necessary: to select the amount (dose) of the yoghurt starter introduced into the prepared milk, and also to investigate the effect of temperature on the fermentation process of the drink; to investigate the amount (dose) of the vegetable filler introduced into the mixture and its effect on the organoleptic characteristics of the drink; to investigate the organoleptic properties of the drink with the melon culture extract added to it before fermentation and after fermentation; to investigate the effect of vegetable filler on the fermentation process; to investigate the effect of the dose of vegetable filler on the process of acid formation; conduct microbiological studies of milk and vegetable yogurt; to investigate the change in the acidity of milk and vegetable yogurt during storage; to investigate the effect of the freezing process on the chemical composition and biological value of the extract. Methods: when performing the practical part of the work, physicochemical, organoleptic and microbiological studies were used. Results and their significance: in the course of the study, it was concluded that by adding an extract of gourds to the technology for the preparation of fermented milk products, a new fermented milk product can be obtained that meets all physicochemical, organoleptic and microbiological requirements. As a result, an original method for the production of a fermented milk drink containing an extract from a melon culture was developed.