EFFECT OF STARTER CULTURE CONCENTRATION ON THE PHYSICOCHEMICAL PROPERTIES OF NATURAL YOGURT

Rezumat

The study analyzes the influence of different concentrations of mixed starter cultures of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus on the physicochemical characteristics of natural yogurt. Yogurt was prepared from milk with 3.5 % fat, to which starter cultures were added at proportions of 0.5 %, 1 %, and 2 % of the milk volume for three separate samples. After homogenization and incubation, the obtained samples were analyzed from a physicochemical point of view. The different concentrations of the starter culture have a direct impact on the quality and physicochemical properties of the yogurt, affecting parameters such as acidity, texture, syneresis, and flavor. The determinations carried out included titratable acidity, fat content, moisture, and pH. The results obtained highlight how the level of inoculation with starter cultures influences the final quality of natural yogurt.