Journal of Food Measurement and Characterization, cilt.18, sa.3, ss.2054-2064, 2024 (SCI-Expanded)
Among the yogurt varieties, concentrated yogurts are produced under various names around the world. During the manufacturing of these products, acidic yogurt whey released as a waste product poses an environmental problem. Therefore, the current study focused on the evaluation of this waste. To that end, this study investigated the use of yogurt whey with reduced acidity as a novel ingredient for the formulation of probiotic beverages, incorporating blackthorn fruit in concentrations of 5–10%. Probiotic beverages without blackthorn were used as a control. The physicochemical, sensorial, microbiological, and functional properties of the samples were investigated over 28 days of cold storage. The dry matter and protein contents of the samples ranged from 6.50 to 8.30% and 0.61–0.67%, respectively, which were higher in beverages containing blackthorn. The beverages containing blackthorn showed higher viscosity (23.58–25.43 cP) than the control. Notably, the antioxidant activity was highest (48.96–54.21%) in beverages with 10% blackthorn. Correspondingly, these samples also had the highest total phenolic (14.17–15.82 mg gallic acid/100 mL) and flavonoid contents (25.25-126.11 µg quercetin/mL). Until the 14th day of storage, blackthorn supported the growth of Limosilactobacillus reuteri. At the end of the storage, probiotic counts remained within the beneficial range (7.55–8.13 log CFU/mL) in all beverages. In general, samples containing 10% blackthorn received high sensorial scores. This research underscores the potential of yogurt whey as an effective ingredient for probiotic beverages, particularly when combined with blackthorn. The findings suggest the use of blackthorn concentrations of ≥ 10% to optimize sensory and antioxidant benefits in future product development studies.