Usage of sourdough with chickpea flour in frozen bread making

In this study, usage possibilities of chickpea flour due to its high nutritive properties were investigated in frozen sourdough bread making. Wheat flour was blended with chickpea flour at the level of 0%, 25% and 50% in the production of Type I sourdough. This sourdough was added in bread dough (30%) and determined the rheological properties, freezable water content (%) and bread making performance before and after frozen storage (-35 °C, 28 days). According to dynamic rheological measurements, storage modulus (G') was not affected significantly by frozen storage in the samples with chickpea flour (p>0,05). The freezable water content (%) was determined as 33% in bread prepared with wheat flour sourdough and as 25% in bread prepared with chickpea flour (25%) sourdough. Frozen storage decreased significantly the spesific volume (mL/g) of the breads prepared with wheat flour sourdough (p<0,05) while no significant effect was observed in the breads with wheat flour sourdough (p>0,05). Type II sourdough was prepared with addition of 0% and 25% chickpea flour in the second part of the study. Frozen storage increased Lactic acid bacteria (LAB) counts by 1 log in Type II chickpea flour sourdough prepared with Torulaspora delbrueckii and Kluyveromyces marxianus, but caused significant reduction in all samples prepared with wheat flour (p<0,05). Type II sourdough formulated with chickpea and wheat flour decreased the volume loss (%) of sourdough breads after frozen storage contrary to Type I sourdough bread (p>0,05). In the last part of the study, sourdough obtained from Afyon/Bolvadin (EH1), Afyon/Tınaztepe (EH2), and Kastamonu (EH3) were stored at -20 °C and thawed five times in total every 15 days. LAB and yeast were isolated after every thawing stage. No significant differences were observed (p>0,05) between the sourdough fresh bread prepared with the strains isolated and identified from fresh sourdough (S.cerevisiae KD0M1 and L.brevis 28C1B3) and the strains isolated and identified from frozen-thawed sourdough (S.cerevisiae KD2M2 and L.brevis KD5B5). Volume loss of Type II sourdough bread prepared with S.cerevisiae KD2M2 and L.brevis KD5B5 was decreased than the other samples in the frozen storage (p<0,05). It was concluded that using of Type II sourdough prepared with yeast and LAB isolated from frozen-thawed sourdough was more suitable and Type II sourdough formulated with chickpea flour provided an advantage in terms of bread quality contrary to Type I sourdough in frozen bread making.