Determination of the microbial flora in traditional İzmir Tulum cheeses by Denaturing Gradient Gel Electrophoresis

J Food Sci Technol. 2018 Mar;55(3):956-963. doi: 10.1007/s13197-017-3003-z. Epub 2018 Feb 6.

Abstract

In this study, it was aimed to determine microbial flora members in three traditional Tulum cheeses (C1, C2 and C3) produced in different villages and settlement areas in İzmir, Turkey. For this purpose, culture depended and 16S rRNA based culture independent methods were used. According to the results of culture depended method, Lactococcus spp., Enterococcus spp., Staphylococcus spp., Lactobacillus spp., Pediococcus spp. and yeast-mold were detected in all samples at different levels. In order to determine and identify both of the culturable and non-culturable microorganisms, denaturing gradient gel electrophoresis (DGGE) method was used. DGGE results have shown that there were eight different dominant microorganisms (Streptococcus thermophilus, Lactococcus lactis subs. lactis, Streptococcus infantarius subs. infantarius, Lactobacillus gallinarum, Streptococcus equinus, Enterococcus faecalis, Enterococcus faecium, Lactococcus garvieae) in three regionally cheese samples. Further more, total bacterial loads were monitored with real-time PCR (qPCR) method. According to the results, 3.5 × 108, 3.8 × 108, 8.4 × 108 copy number of DNA was detected in C1, C2 and C3 cheese samples, respectively. This study is the first description for the dynamics of microbial composition of Izmir Tulum cheese after the production and brining processes.

Keywords: Cheese microflora; DGGE; Nested PCR; Real-time PCR (qPCR); İzmir Tulum cheese.