The effects of different incubation temperatures on the acetaldehyde content and viable bacteria counts of bio‐yogurt made from ewe's milk

Yogurt and bio‐yogurt were manufactured from ewe's milk using a starter culture and a probiotic culture. Incubation was carried out at 37°C and 42°C until pH 4.6 was reached and the yogurts were stored at 4 +1°C for 14 days. Analysis after 1, 7 and 14 days showed that incubation temperature and storage time significantly influenced overall properties of the samples. During the storage, whey separation and pH decreased, but titratable acidity, lactic acid and volatile fatty acid contents increased. Viable bacterial counts in all bio‐yogurts were above 107 cfu g−1 at the end of storage.