Evaluating the potential of locally isolated yeast for the production of bread from wheat-cassava composite flour

There is growing interest in the use of composite flour (wheat-cassava) for bread making owing to some economic, social and health reasons. Yeast (Saccharomyces cerevisae) plays essential role in the fermentation process of baking. One major challenge of the production of composite bread is the use of commercial baker’s yeast. To ensure the success of this composite wheat-cassava flour technology, the research aimed at addressing the area of the effect of applying various yeast isolate on bread produced from wheat-cassava composite. A total of six yeast strains isolated from palm wine and honey were screened. Two strains identified as Saccaromyces cerevisae, designated SPW1 and SH3 in addition to commercial yeast (CY) were studied using varying concentration (1%-3%); wheat-cassava composite used was in the ratio of 90w:10c. Loaf volume, organoleptic properties i.e. colour, texture, aroma, taste and general acceptance were evaluated. In both bread baked with wheat-cassava composite and 100% wheat, best results were obtained with SPW1 followed by CY and SH3 at concentration of 1%, 1.5% and 2% with a corresponding average loaf volume of 854cm³, 786cm³ and 539cm³ respectively. In terms of sensory evaluation of aroma, colour, taste, crust and general acceptability, bread produced with SPW1 was most preferred followed by CY and SH3. With emphasis on the use of locally available resources and current economic situation the use of indigenous yeast may enhance production of composite flour for consumption.