Fermented beverage production using demineralized whey powder with different probiotic starter cultures

The aim of the study is to produce functional whey by fermenting the whey produced by adding demineralized whey powder and lactulose as a prebiotic source, with different probiotic starter cultures. Probiotic starter cultures used for fermentation are Lacticaseibacillus rhamnosus, Lacticaseibacillus reuteri, Lacticaseibacillus gasseri, Bifidobacterium animalis subsp. lactis BB12 and Propionibacterium freudenreichii subsp. shermanii. The produced fermented whey drinks were stored at +4 ºC for 28 days and physical, chemical, microbiological and sensory analyzes were performed on the 1., 7., 14., 21. and 28. days of storage and the results were evaluated statistically. Differences in dry matter, ash, protein and carbohydrate values between fermented whey beverages were found to be insignificant (p>0.05). Differences in acidity values among fermented beverages during storage were found to be significant (p <0.05). In fermented beverages, B. lactis BB12 viability was detected at 8 log kob/ml, L. rhamnosus viability at 9 log kob/ml, L. reuteri viability at 8 log kob/ml, L. gasseri viability at 9 log kob/ml. As a result of microbiological analysis of the fermented whey beverages produced, it was observed that lactulose supports the growth of microorganisms and maintains the probiotic level of microorganism viability throughout the storage process. The viability P. freudenreichii subsp. shermanii varies at levels of 9 log kob/ml. Sensually, the beverage fermented with B. lactis BB12 was appreciated the most, while the beverage fermented with L. reuteri was appreciated the least. When the results obtained were evaluated, it was seen that the shelf life properties of the functional fermented beverages produced were suitable for industrial production.