Journal of Dairy Research

Journal of Dairy Research (2005), 72:1:19-24 Cambridge University Press
Copyright © Proprietors of Journal of Dairy Research 2005
doi:10.1017/S0022029904000536

Homofermentative lactic acid bacteria of a traditional cheese, Comlek peyniri from Cappadocia region


Cisem Bulut a1, Hatice Gunes a2, Burcu Okuklu a2, Sebnem Harsa a1, Sevda Kilic a3, Hatice Sevgi Coban a2 and Ali Fazil Yenidunya a2c1
a1 Izmir Institute of Technology, Biotechnology Programme, 35430 Gulbahce, Urla, Izmir, Turkey
a2 Department of Biology, Science Faculty, Izmir Institute of Technology, 35430 Gulbahce, Urla, Izmir, Turkey
a3 Ege University, Faculty of Agriculture, Department of Dairy Technologies, Bornova, Izmir, Turkey

Article author query
bulut c   [PubMed][Google Scholar] 
gunes h   [PubMed][Google Scholar] 
okuklu b   [PubMed][Google Scholar] 
harsa s   [PubMed][Google Scholar] 
kilic s   [PubMed][Google Scholar] 
sevgi coban h   [PubMed][Google Scholar] 
fazil yenidunya a   [PubMed][Google Scholar] 

Abstract

Comlek peyniri is a typical artisanal cheese in Central Anatolia. This type of cheese was made by using the indigenous lactic acid bacteria (LAB) flora of cow or ewes' milk. Majority of the samples were taken from fresh cheese because the aim was to isolate homofermentative LAB. Initially 661 microbial isolates were obtained from 17 cheese samples. Only 107 were found to be homofermentative LAB. These isolates were selected and identified by using both phenotypic and molecular methods. Phenotypic identification included curd formation from skim milk, catalase test, Gram staining and light microscopy, growth at different temperatures and salt concentrations, arginine hydrolysis, gas production from glucose, and carbohydrate fermentation. Molecular identification was based on the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) of the 16S rRNA gene-ITS (internally transcribed spacer) region. By combining the phenotypic and molecular identification results, isolates belonging to each of the following genera were determined at species or subspecies level: 54 Lactococcus lactis subsp. lactis, 21 Enterococcus faecium, 3 Ec. faecalis, 2 Ec. durans, 10 Ec. sp., 15 Lactobacillus paracasei subsp. paracasei, and 2 Lb. casei strains. Technological characterisation was also performed by culturing each of the strains in UHT skim milk, and by monitoring pH change and lactic acid production at certain time intervals through the 24 h incubation. Results of the technological characterisation indicated that 33% of the isolates (35 strains) were capable of lowering the pH of UHT milk below 5·3 after 6 h incubation at 30 °C. Thirty four of these strains were Lc. lactis subsp. lactis, and only one was an Ec. faecium strain.

(Received December 12 2003)
(Accepted May 28 2004)


Key Words: Identification; homofermentative lactic acid bacteria; 16S rRNA gene-ITS RFLP.

Correspondence:
c1 e-mail: afazilyenidunya@iyte.edu.tr