Effect of sweetener supplement on the viability of Lactobacillus acidophilus La 5, Bifidobacterium animalis subsp lactis Bb 12 and Streptoccus thermophilus St 36 in fermented goat milks during storage

This research studied the effect of milk supplementation with inulin, oligosaccharide, polydextrose, fructose and saccharose on the viability of probiotics in fermented goat milk during refrigerated storage (21 days). Sweetener supplements were added to UHT goat milk at the rate of 3.0% while a control sample was also maintained without any added supplements. Control and supplemented milk samples were fermented by a commercial starter culture containing Lactobacillus acidophilus La 5, Bifidobacterium animalis subsp. lactis Bb 12, and Streptococcus thermophilus St 36. Inoculated samples were incubated at 37 degrees C for 8 h and stored at 4 degrees C Estimation of microbial viability was carried out at days 1th, 7th, 14th, and 21th in triplicates from each batch. The results showed that, during the storage period, the viability of probiotic bacteria in fermented goat milk was not notably lower than control milk. In general, inulin and polydextrose added fermented goat milk samples demonstrated higher viable bacteria counts than other supplemented milk samples at the end of storage. All fermented milk samples contained the recommended levels (6-7 Log cfu ml-1) of probiotic bacteria except Bifidobacterium animalis subsp. lactis Bb 12 at the end of the 21-day shelf life.