Full Length Research Paper

Some technological properties of phenotypically identified enterococci strains isolated from Turkish tulum cheese

Yasin Tuncer

Faculty of Engineering and Architecture, Department of Food Engineering, Süleyman Demirel University, 32260 Isparta, Turkey.

E-mail: ytuncer@mmf.sdu.edu.tr. Tel: +90 246 211 17 13. Fax: +90 246 237 04 37.

Accepted 6 November, 2009

   Abstract

In this study, a total of 39 enterococci strains were isolated and identified as 17 Enterococcus faecium (43.58%), 11 Enterococcus faecalis (28.21%) and 11 Enterococcus durans (28.21%) strains from 28 Tulum cheese samples from Isparta, Turkey. Three E. faecium (EYT6, EYT21 and EYT34) and 1 E. durans (EYT16) strains showed α-hemolytic activity on Sheep Blood Agar. None of the all strains exhibited β-hemolysis. All of the 39 enterococci strains were sensitive to vancomycin (30 μg vancomycin per disk, inhibition zone > 12 mm). Three E. faecium (EYT17, EYT31 and EYT39) and 1 E. durans (EYT19) strains were found as bacteriocin producer. E. faecium strains showed higher acidifying ability than E. faecalis and E. durans strains. The highest proteolytic activity value (100.5 μg tyrosine/ml) was obtained from E. faecalis EYT18. Proteolytic activity results showed that E. faecalis strains generally more active than E. faecium and E. durans strains. E. faecalis strains were found the most lipolytic, followed by the E. faecium and E. durans strains and E. faecalis EYT7 strain gave the maximum halo radius (0.53 mm). None of the 39 enterococci strains decarboxylated histidine, lysine or ornithine. However, 36 of the 39 strains (92.31%) produced tyramine from tyrosine.

Key words: Enterococci, tulum cheese, industrial properties.