Microbiology Research Journal International

Consumption of bread and other baked aerated wheat flour products has spurred the needs to determine the leavening ability of different brands of baker’s yeast used in bread production. In this study we assessed the leaving ability of different brands of baker’s yeast in production of quality bread and the flour used in baking test was Dangote flour. Seven brands of different commercial baker’s yeast were collected from the 13 different brands sold in Jos market. These brands includes: Angel instant active dry yeast (ANGY), Saf-instant active dry yeast (SAFY), Food mont instant active dry yeast (FOMY), Pasha instant active dry yeast (PASY), STK- Royal active dry yeast (ROYA), Vahine active dry yeast (VAHY) and Fermipan active dry yeast (FEMY). The results of the viability tests for the different brands of active dry yeast indicated that six out of the seven brands were 100% viable while one had only one dead cell. Statistical analysis (one-sample-t- test) revealed that there was significant different among the different brands of yeasts used (p<0.05), however ANGY had the highest performance viability (p<0.002) and PASY had the least (p<0.039) as shown in Table 3 in appendix. The result of the pH variation as function of time at 26⁰C shows steady decrease in pH values of all the different brands of yeast suspension. Using regression analysis, pH at 150 minutes contribute  96 percent to the leavening ability of different brands of baker’s yeast used in  bread production and 30 minutes contribute the lowest 9.1 percent as shown in the Table 4 in the appendix. It was concluded that all the seven brands of baker’s yeast tested were suitable for use in bread production when compared with the standard.