Determination of the quality characteristics and spoilage yeasts of şalgam beverage

In this study, it was aimed to determine the quality characteristics of five different spoiled shalgam beverages collected from the market and to determine the spoilage yeasts. During the molecular identification of yeasts, PCR-RFLP technique was used and the sequence of the D1/D2 region of 26S rRNA gene was obtained. While pH values of shalgam beverages collected from the market varied between 3.86 - 4.10, the total acidity values in terms of lactic acid ranged from 5.33 to 8.36 g/L. In shalgam samples 4 and 5, a* values were low although L* values were quite high in comparison to control sample. As a result, it was determined that these two samples deviated from the standard color of shalgam beverage. The carbon dioxide values of shalgam samples 4 and 5, leading bulging problem, were measured as 0.75 and 1.73 g/L, respectively. A total of 103 yeast isolates were identified belonging to nine different species and nine different genera in shalgam beverages. Saccharomyces cerevisiae was determined as a dominant yeast species followed by Galactomyces candidum and Pichia kudriavzevii.