Production of sour maize bread using starter-cultures

摘要

Eight lactic acid bacteria were isolated from fermenting maize meal. They were identified as Lactobacillus brevis, L. casei, L. fermentum, Pediococcus acidilacti, P. pentosaceus, Lactobacillus spp. I and Pediococcus spp. I and II. L. brevis and Lactobacillus spp. I isolated from the spontaneously fermented maize meal together with brevis isolated from L. rye sour dough and L. from ogi, a fermented maize gruel, were selected as starter organisms. There was a plantarum decrease in the final pH from 4.9 to 3.8 and an increase in the acid equivalent and temperature of the spontaneously-generated sour maize meal at the end of 24 h fermentation. There was a decrease in the pH and moisture content of the sour maize breads relative to the conventional wheat bread. An improvement in the shelf-life of the bread samples was also obtained. Crude protein values of the sour maize breads were between 4.36% and 8.87%, while crude fat contents ranged between 3.66% to 7.67%. The ash contents increased from 2.29% to 2.54% while total carbohydrate values were between 46.31% and 65.3%. Calcium, phosphorus and potassium contents ranged from 0.015, 0.26 and 0.018% to 0.036, 0.47 and 0.036% respectively. Physical examination of the bread samples showed that all were cracked and relatively hard. Weight, height and volume ranged from 316 to 380 g; 4.2 to 5.2 cm and 200 to 320 cm(3) respectively. Statistical analysis of the sensory attributes revealed a consumer acceptance of the sour maize breads, although ranking test showed preference for the baker's yeast leavened bread that served as a control.