Probiotics viability in frozen yogurt supplemented with oligofructose and glycerol

Functional foods are very common nowadays throughout the world due to their nutritional and health benefits. The present study was designed to see the viability of yogurt culture and probiotics in frozen yogurt when supplemented with oligofructose and glycerol. Different types of yogurt culture (Streptococcus thermophilus and Lactobacillus bulgaricus) and probiotics (Lactobacillus acidophilus and Bifidobacterium lactis) were used for the preparation of frozen yogurt mixture. Furthermore, oligofructose(2%, 4%, and 6%) along with glycerol (1%, 2%, 3%, and 4%) were also used to improve the cultures viability. During analysis the viable count before freezing, after freezing and after every three weeks regular interval was done up to 12 weeks. The results have shown that the viability loss of S. thermophilus and L. bulgaricuswere recorded 0.3 and 0.36 log cyclesduring freezing which were further decreased as1.14 and 1.68log cyclesrespectively, at the end of storage. While, in L. acidophilus and B. lactiscultures this reduction wasobserved0.5 and 0.14log cyclesin freezing process which further reduced as 2.29 and 2.81log cycles respectively after 12 weeks.