Identification and technological characterization of Lactococcus isolated from traditional Turkish cheeses

Abstract

Thirty seven strains of Lactococcus laths subsp. locus and 5 strains of L. locus subsp. cremoris isolated from White Pickled and Kashar cheeses were identified according to phenotypic and molecular techniques using subspecies specific primers. Then, acidification, proteolysis and autolysis of strains were assessed in order to select bacteria for starter development. The strains were divided into slow, moderate and rapid acidifying groups according to their acidifications (P < 0.05) in reconstituted skim milk (RSM). Acidification of strains from White Pickled cheese was significantly higher (P < 0.05) compared to those of Kashar. Majority (86%) of the isolates exhibited Prt(+) phenotype. Bacterial autolysis which was tested under starvation conditions evidenced that strains have an autolytic extent at the end of 24 h ranging from 37 to 70%. The results of this study showed a large diversity among the isolates and provide criteria for choosing strains to be tested as starters in cheesemaking. experimentation.