Çiğdem Konak Göktepe, Neşe Mutlu, Talha Demirci, Aysun Oraç, Nihat Akin, Lütfi Pirlak
This study evaluated the impact of Aronia melanocarpa puree (2% and 6%) and Lactobacillus (L.) acidophilus DSM 20079 on yogurt quality during 28 days of storage, with emphasis on physicochemical, microbiological, and biofunctional properties. Acidification kinetics varied with formulation, with yogurt B (6% aronia+probiotic) reaching pH 4.6 faster (194 ± 2 min) than yogurt A (2% aronia+probiotic; 233 ± 2 min). The addition of aronia reduced hardness while enhancing water holding capacity. It also enhanced functional properties, with 6% aronia and L. acidophilus DSM 20079 increasing total phenolic content by 71.04% and DPPH activity by 414.93% compared to the control. Yogurt B exhibited the highest α-glucosidase inhibitory activity on Day 28 (33.23%), whereas the control showed 12.21%. ACE inhibitory activity was enhanced only in probiotic-containing yogurts. In addition, antioxidant bioaccessibility peaked during intestinal digestion, where FRAP values increased by up to 435.80%. Sensory evaluation indicated that the addition of probiotics to aronia-enriched yogurts positively influenced overall sensory quality scores, although stirred-type samples received the lowest scores (5.08) by Day 28. Throughout storage, L. acidophilus DSM 20079 counts remained above the recommended probiotic threshold of 6 log CFU/g, ensuring the functional probiotic potential of the product. These findings highlight the potential of aronia and probiotic supplementation to improve the functional and sensory properties of yogurt, offering a promising strategy for the development of functional dairy products.