RESUMO
Currently, products with a reduced content of saturated fatty acids and a high protein content occupy an important place in the structure of a balanced diet, which leads to an increasing demand for cheeses with a low content of milk fat and high organoleptic properties. As a result of the growing trend towards the consumption of products with a reduced calorie content, there is a scientific interest in the development of technologies for low-fat cheeses with high consumer characteristics that are not inferior to analogues with a fat content of 45-50%. However, low-fat cheeses produced using existing technologies, as a rule, are characterized by low organoleptic properties, including an unexpressed taste and aroma and a rough, rubbery texture. The purpose of the research was to develop a low-fat cheese with high organoleptic characteristics, produced using not only the main acid-forming microflora, but also adjunct bacterial cultures that enhance enzymatic processes during cheese ripening and have probiotic properties. Material and methods. The production of low-fat cheeses (options 2 and 3) with a fat mass fraction of 20% in terms of dry matter was carried out according to a single technological scheme, which ensures the manufacture of cheese after pressing with a mass fraction of moisture of 53-54%. As a control option (1), Dutch cheese was produced with a fat mass fraction of 45%. Bulk starter containing a mixture of lactococci of the Lactococcus lactis species was used as the main acid-forming starter microflora in all cheese options (1, 2, 3); in low-fat cheese option 3, adjunct cultures of Lactobacillus casei and Propionibacterium freudenreichii were added. During ripening, cheeses were subjected to microbiological (total quantity of viable cells of lactic acid microorganisms, Lactobacillus casei and Propionibacterium freudenreichii), physicochemical (mass fraction of lactose, fat, moisture, solids, protein) and organoleptic studies. The total quantity of viable cells of the mesophilic lactic acid microflora was determined by the quantity of mesophilic aerobic and facultative anaerobic microorganisms. In cheeses after the end of the ripening process, the molecular mass distribution of soluble nitrogenous compounds and the content of flavoring substances in the vapor phase were additionally evaluated. Results. It has been established that in low-fat cheeses, the mass fraction of protein increases by 5.9±0.1% with a decrease in the proportion of fat to 20.0%. In this regard, the calorie content of low-fat cheese reduced by a third. It has been demonstrated that differences in the composition of the starter microflora had a significant impact on the depth and direction of biochemical processes, the formation of flavoring substances, which lead to an improvement in the organoleptic characteristics of cheeses. Conclusion. The addition of adjunct cultures of Lactobacillus casei mesophilic rods and Propionibacterium freudenreichii propionic acid bacteria, together with technological methods, contributes to the formation of a pronounced cheese taste and aroma, improves the flavor profile and deepens the process of proteolysis in cheeses with a fat mass fraction of 20% and brings their consumer properties closer to those of cheese with a fat content of 45%.
