Akademik Veri Yönetim Sistemi
Food Bioscience, cilt.82, 2026 (SCI-Expanded, Scopus)
This study evaluated the influence of milk type (A1 and A2) and the incorporation of Pediococcus acidilactici GD-1 as an adjunct culture on the sensory, microbiological, physicochemical, and functional characteristics of kefir, including amino acid composition, γ-amino butyric acid(GABA) and exopolysaccharide (EPS) production, and in vitro antidiabetic and anti-inflammatory activities. Kefir samples from A1 or A2 milk were produced using commercial kefir culture alone or in combination with P.acidilactici GD-1. According to sensory evaluation, significant differences were observed only in mouthfeel and consistency (p<0.05), and A2C received the highest scores in those attributes. The smell, appearance, taste, sourness, and overall acceptability did not differ significantly among kefir samples (p>0.05). A1CP and A2CP exhibited the greatest α-amylase inhibitory potential. However, there was no statistically significant difference in terms of α-glycosidase inhibition among all samples. A1CP displayed the highest in vitro anti-inflammatory activity. Although P.acidilactici GD-1 is a known GABA-producing strain, its addition did not consistently increase GABA levels, suggesting that its effect in kefir depends on fermentation conditions and microbial interactions. A2 milk increased the kefir's EPS content, and incorporating P.acidilactici GD-1 contributed to higher EPS levels. The findings suggest that both milk composition and fermentation conditions play important roles in determining kefir's functional characteristics. However, since the functional properties were evaluated only through in vitro analyses, further in vivo and clinical studies are needed to confirm their physiological relevance. Additionally, optimisation studies are required to enhance GABA production and better clarify the strain-specific contribution of P.acidilactici GD-1 during kefir fermentation.