Investigation of the Bread Baking Potentials of Some Ascosporogenous Yeast Strains Isolated from Palmwine

Abstract

Yeast is the primary organism responsible for the leavening of doughs. In this study, yeast samples were isolated from palm wine samples collected from Nkpa in Abia State. The samples were cultured on malt extract agar (MEA) medium at room temperature of 28^oC to isolate three ascosporogenous yeast strains (Saccharomyces fragilis, Saccharomyces cerevisiae, Pichia spp) from the culture by using identification techniques such as their morphological, fermentative and microscopic properties. The isolated yeast, the combination of the strains and the commercial baker’s yeast as the control were each used to produce eight different bread samples and their physical, sensory properties and correlation were examined. Amongst the bread samples examined for physical properties, sample D (Baker’s yeast) had the highest value in bread volume followed by Saccharomyces cerevisiae while Pichia spp had the least performance. Likewise, significant differences (p < 0.05) occurred in specific volumes, which ranged from 1.91 – 3.94. The loaf weight ranged from 276.5- 320.1g.  The result of the sensory attributes of the bread samples revealed that the taste value ranged from (4.3 -8.5), texture (3.5 -8.0), aroma (3.5 -8.0), crust colour (4.4 – 8.0), and general acceptability (4.7 -7.9).  The general acceptability was significantly (p < 0.01) found to be positively correlated with bread volume (r = 0.96), taste (r = 0.90), crust colour (r = 0.86) and negatively correlated with the loaf weight (r = −0.86). Therefore, the data shows that some of the isolated yeast strains and the combination of strains could be valuable in the leavening of doughs.

Keywords: Palm-wine, Ascosporogenous yeasts, Bread, Physical properties, Sensory properties

DOI: 10.7176/FSQM/121-07

Publication date: January 31^st 2023