Abstract
Carotenoids are organic pigments with antioxidant properties that are commonly found in nature. Various types of carotenoids are produced by microorganisms. In this study, we aimed to determine the microorganisms with potential carotenoid production and yellow-orange pigment production during the storage of white cheese below 10°C. Five different white cheeses with pigmentation problems were obtained from the provinces of Istanbul and Kocaeli. Colonies with a typical yellow-orange color and morphological differences were selected on MRS and M17 media. The presence of carotenoid genes in 136 selected colonies was determined by agarose gel electrophoresis using colony PCR, and carotenoid genes were detected in 6 colonies. According to the 16S rRNA sequence results, one of the 6 bacterial colonies carrying the carotenoid gene was Lactococcus lactis, another was Enterococcus faecium, and the rest was Lactobacillus plantarum. In addition to genotypic identification, Gram-staining was performed to determine the phenotypic characteristics of bacteria carrying the carotenoid gene, and it was found that six bacteria had Gram-positive and bacilli morphology. These results showed that some carotenoid producer strains existed in the microbioata of cheeses during cold storage.