Microbiological and Chemical Properties of Siahmazgi Cheese, an Iranian Artisanal Cheese: Isolation and Identification of Dominant Lactic Acid Bacteria

Abstract

In this study, the chemical and microbiological properties of Siahmazgi cheese, an Iranian artisanal cheese made of unheated ewe and goat milk without addition of starter culture, were evaluated. The pH of the samples ranged from 4.76 to 5.18. The average numbers of total viable count and lactic acid bacteria (LAB) in cheese samples were 3.7 × 106 and 6.9 × 106 cfu/g, respectively. Coliforms and Enterobacteriaceae were absent in all the samples. A total of 125 LAB isolates were selected according to their Gram-positive and catalase-negative characteristics, out of which 23 strains were cocci and 102 were lactobacilli. Identification of the selected isolates was done through biochemical tests and 16s rDNA sequencing. Isolated strains were identified as Lactobacillus plantarum group (41.6%), Lactobacillus brevis (39.2), Lactobacillus parabuchneri (0.8%), Enterococcus faecium (13.6%), Enterococcus durans (3.2%) and Pediococcus parvulus (1.6%). The results of this study showed the microbiological diversity of traditional Siahmazgi cheese. Practical Applications Exploring the microbiological diversity of traditional dairy products is required for selection of appropriate strains to manufacture the products with consistent quality and original taste on industrial scale.