Abstract Lactobacilli, as the largest group of lactic acid bacteria, produce large amounts of bioactive metabolites which make them suitable for many technological application such as inhibition the growth of pathogenic bacteria and increase the shelf life of foods. The aim of this study was to evaluation the technological characteristics of Lactobacillus spp. isolated from Iranian raw milk Motal cheese. For this purpose, Sixteen lactobacillus spp. Previously isolates from traditional Motal cheese and identified by biphasic approach were examined in terms of rate of acid production, biogenic amine production, . proteolytic, lipolytic, autolytic, amylolytic activities as well as extracellular polysaccharide (EPS) production. Furthermore, study of the property of Gamma-aminobutyric acid (GABA) production and susceptibility to antibiotics and acid resistance test were also evaluated. Most of the lactobacilli displayed high proteolytic and autolytic activities and low acidifying activity, except for Lactobacillus plantarum KX572393 (M19) which had a proper acidification and reduced the pH to 4.6 after a twelve-hour incubation at 37 ° C. The majority of examined strains possessed high proteolytic activity, with the highest clear zone of inhibition equal to 30 mm for lactobacillus brevis KX572378 (M4). None of the isolates were biogenic amine producer and lipolytic activity. The highest percentage of antibiotic resistance was belonged to kanamycin (30 mg/disc) (87%) except Lactobacillus plantarum KX572390 (M16) and Lactobacillus plantarum KX572393 (M19). All isolates were sensitive to chloramphenicol except Lactobacillus brevis KX572385 (M11), and none of the isolates were resistant to erythromycin. Extracellular polysaccharide production was not detected in any strain when compared with leuconostoc mesenteroides subsp. mesenteroides ATCC 8293, as reference or positive control. Acid resistance showed that all isolates were able to grow in pH 3 and 4 but only 4 strains were grown in pH 2 including Lactobacillus brevis KX572386. As a conclusion, lactobacillus brevis KX572378 (M4) presented the best technological characteristics. For these reason, this strain could be good candidate for inclusion as adjunct culture in a manufacture of industrial Motal Cheese.

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