INVESTIGATING THE MICROFLORA OF IRANIAN TRADITIONAL SOURDOUGH

Background and Aim:Sourdough contains flour, water and other additives (such as NaCl), which is fermented by a heterogeneous population of microorganisms including yeast and Lactic acid bacteria (LAB). The aim of this study is to investigate the microflora of traditional sourdough of Taftoon bread and to describe the chemical features of sourdough. By using methods based on cultivation of microorganisms and chemical analyses (the final titratable acidity and pH), the bacterial and yeast populations of sourdough and its chemical features have been investigated and described. In general, just 3 types of bacterial colonies and 25 yeast strains were isolated from sample of traditional Taftoon sourdough.The total number of bacterial colonies was 1.8*106 colony in each sample gram (cfu/gr), while the total number of yeasts was much lower, about 5.6 * 102cfu/gr. pH sourdough was 3.24 and its final titratable acidity(TTA) was 23.8 ml from 0.1 normal NaOH on 10-grams sample of sourdough.Methods:Data collection:Sourdough sample. pH determination:Digital pH METER.Results:Chemical features of traditional sourdough: Average pH of sourdough was 3.24 and its average final titratable acidity was 23.8 ml via normal 0.1 NaOH on 10g sourdough. LAB count and yeast: The total number of LAB colonies in sourdough was 1.8*106 cfu/g, while the total number of yeasts was much lower and approximately 5.6*102cfu/g. In general, 18 LAB strains and 25 yeast strains were isolated from this sample.Conclusion:The density of microorganism in Iranian traditional sourdough is less than sourdough of European breads,that is the difference of these two types of sourdoughs.

کلیدواژه ها:

sourdough ، yeast ، LAB ، final titratable acidity ، pH