Fate of some pathogenic bacteria and molds in Turkish Tarhana during fermentation and storage period.

Abstract

The survival of the molds and some pathogenic bacteria such as E. coli O157:H7, S. aureus, S. typhimurium and B. cereus during fermentation and storage period of tarhana (traditional Turkish fermented food) was investigated. Tarhana batches were produced with two different yogurt/flour ratio 0.5 (T1) and 0.75 (T2). The pH and Eh values of samples were around 4.0-4.5 and 130-160mV during fermentation and storage period in both batches, respectively. Moisture and aw values in T1 and T2 samples significantly decreased (p < 0.05) between the 3rd-7th days of production at 11.2-11.6% and 0.52-0.54, respectively. The numbers of S. aureus and S. typhimurium significantly decreased (p < 0.05) during the 1st and 2nd days of fermentation period, respectively and this decline gradually proceeded in both batches. No significant differences (p > 0.05) were observed in both tarhana batches among the molds, E. coli O157:H7 counts during the 1st, 2nd days of fermentation, and B. cereus counts during the all days of fermentation and storage periods, except the16th day of storage.