Production of probiotic yogurt containing green tea and Lactobacillus gasseri, effective against obesity

In this study, it was aimed to realize an effective probiotic yogurt production against obesity was carried out by using 1/1 ratio of Streptococcus thermophilus and Lactobacillus gasseri cultures and adding %2, %3 and %4 green tea. Pasteurized cow's milk was used in the production of yogurt. Yogurt samples were stored at 4 °C for 21 days. Physicochemical, microbiological and rheological analyzes were performed on the 1 st , 7 th , 14 th and 21 st days of storage, and the others were performed on the 1 st day of storage. The difference between the storage days and the difference between the yogurt samples on all storage days in terms of pH (4,34-4,76), titratable acidity (%1-%1,24), dry matter (%17,84-%20,70), serum separation (%20,80-%28) and water holding capacity (%49,8-%56,9) values of the yogurt samples were statistically significant (p<0,05). According to the result of the color analyses, the difference between the yogurt samples in terms of L* (89,21-92,51), a*(-0,85-(-0,38)), b* (12,79-15,09) values was found to be statistically significant (p<0,05). As the amount of green tea increased in yogurt samples, an increase in the content of phenolic substances was also observed. As a result of microbiological analyses, it was determined the numbers of Lactobacillus gasseri in the sample containing %2 green tea were above the lower limit (10 6 cfu/g) determined for the acceptance of a food as probiotic during storage (1,53×10 6 - 9,47×10 6 cfu/g). It was determined that the probiotic yogurt sample containing %3 green tea has the best rheological properties. In order to obtain a product that can retain its probiotic feature during storage, it was concluded that the rate of L. gasseri added to yogurt milk should be increased and the rate of green tea that can be used for an acceptable taste and aroma should be %2 or less.