摘要：Sour dough is obtained through addition of spontaneous fermented dough into fresh dough. Two main types of microorganisms can be distinguished in a sour dough, namely bacteria and yeasts. The bacteria, especially Lactobacillus spp . produce mainly lactic acid. The yeasts are responsible for the leavening action. In this study related with this subject species of yeasts which were isolated from samples of sour dough used in Elazığ and villages are the following: Saccharomyces cerevisiae , S. rouxii , S. rosei , S. delbrueckii , Torulopsis holmii , T. stellata and T. unisporus . In the same study the following species of bacteria were isolated from the samples of sour dough which was gathered: Lactobacillus plantarum , L. casei , L. brevis , L. fermentum , L. fructivoran and Pediococcus pentosaceus . The number of lactic acid bacteria which corresponds to 1 g dried sample in bakery is found to be 7.56x108 in the sour dough towards the last period of fermentation. In the same sample the number of yeast is 2.23x108/g sample. In samples of sour dough which were prepared at laboratory and left at the fermentation we determined that the pH value was 4.15 at the last period of fermentation.
