Abstract

Depending on ochratoxin A (OA) concentration, changes in OA content of wort and beer were determined during beer fermentation using Elisa method. After 10 days of fermentation, OA content of sample A, which includes approximately 10 ppb added OA, decreased 24.97 % while this figure was 18.74 % in sample B which was contaminated with 20 ppb OA. In sample C, which includes 30 ppb added OA, the level of OA decreased (8.9 %) less than the other two samples. Degradation ratio of OA decreased as the OA concentration increased during fermentation. OA concentration negatively affected yeast growth during fermentation and therefore yeast growth was lower in OA containing samples than the others. The wort samples which contain high concentration of OA had lower yeast count compared with control group and wort samples containing low concentration of OA. A gradual decrease has been observed in pH value of the samples including high level of OA compared to these samples contaminated with low level of OA. Alcohol concentration of the samples decreased as OA concentration increased. At the beginning of fermentation, total sugar ratio of all samples was 6.62 %. However, total sugar values were found higher in the samples which contained at high levels of OA.