بررسي ميزان استالدييد در ماست هاي توليدشده به وسيله سويه هاي ميكروبي بومي

Evaluation of Acetaldehyde Content in Yogurts Produced by Native Microbial Strains

Among fermented milk products, yogurt is more famous than others and might be regarded as an acceptable and popular product. In this study, native microbial strains isolated from two traditional yogurt samples (Gilan and Golpayegan) were used for yogurt production. Acetaldehyde content of yogurts produced by native starters was measured by GC. Produced yogurts were stored at 4°C for three weeks. The aim of this study was to evaluate the variations of acetaldehyde content of produced yogurts during cold storage. There was a significant increase (p<0.05) in acidity and a significant decrease (p<0.05) in pH of produced yogurts during cold storage. Moreover, acetaldehyde content increased significantly (p<0.05) and reached a maximum concentration after 21st day.