Probiotic Viability and Bioactive Properties of Buffalo Yoghurt Produced Using High Cholesterol-Assimilating Probiotic Strains

BackgroundThis study aimed to produce yoghurt with reduced cholesterol levels, enhanced antioxidant activity and angiotensin-converting enzyme (ACE) inhibitory activity while maintaining acceptable health properties, using buffalo milk and probiotic microorganisms.MethodBuffalo yoghurts were produced using three different probiotic strains, including Lactobacillus acidophilus, Lactiplantibacillus plantarum and Bifidobacterium lactis. ACE-inhibitor activities (%), antioxidant activities as DPPH (%), and cholesterol activities in HPLC of these yoghurts were determined during the 28-day storage period. In addition, probiotic microorganisms, total aerobic mesophilic bacteria and yeast mould were counted during storage.ResultsThe viability of probiotic microorganisms in buffalo yoghurts remained above 5 log CFU/g at the end of the storage period. Antioxidant activity ranged from 9.30% to 27.20%. Buffalo yoghurt is produced with Lpb. plantarum, which exhibited the highest viability (9.12 log CFU/g) and antioxidant activity values of 61.48%. Gastrointestinal digestion affected the antioxidant and ACE-inhibitor properties of the yoghurt samples. The highest ACE-inhibitory effect after gastric digestion on the 28th day was observed in yoghurt-produced Lpb. plantarum and B. lactis, with 24.30% and 25.14% values, respectively. Also, the ACE-inhibitory activity of the outer (OUT) phase for all yoghurt samples was higher than that of undigested samples. According to cholesterol peaks obtained in HPLC, the highest cholesterol assimilation was detected in yoghurt produced using Lpb. plantarum.ConclusionThe data obtained from the study may contribute to research on the potential of probiotic microorganisms with cholesterol-assimilation ability and probiotic food products produced using them to reduce cholesterol risk.