Zahra Farahani - Department of Biology, Shahed University, Tehran-Qom Express way, Tehran, Iran
Iraj Rasooli - Department of Biology, Shahed University, Tehran-Qom Express way, Tehran, Iran
Leila Hajiabadi - Department of Microbiology, Islamic azad university, ۱۵ Khordad Boulevard, Qom, Iran

The presence of Lactic Acid Bacteria (LAB) in fermented foods improves the health safety of food. Flavour de-velopment in dairy fermentations rises from a series of biochemical processes. Whereas autolysis and proteolysis activity by lactic acid bacteria are important factors in dairy industry, with the aim of improvement of dairy qual-ity in food industry, bacteria with high autolysis and proteolysis activity were isolated and identified in this study. From local raw milk samples, a total of 26 isolates were screened by Lactic Acid Bacteria specific growth culture media; M17, KA and MRS, under the aerobic and microaerophilic conditions. Autolysis activity of these 26 iso-lates were studied with the percentage decrease of the OD600nm after 48 h, and proteolysis activity were studied with the clear zone around each colony were spotted on skim milk medium, respectively. Finaly some of the local bacteria with the aim of improvement of dairy products screened and identified, that can be used in food industry

Lactic Acid Bacteria, Autolysis, Proteolysis, flavour improvement