This study was aimed at selecting starter cultures for bio-enriching ogi (fermented cereal gruel) using folate-producing microorganisms. The folate-producing microorganisms were isolated by incorporating folate analog...This study was aimed at selecting starter cultures for bio-enriching ogi (fermented cereal gruel) using folate-producing microorganisms. The folate-producing microorganisms were isolated by incorporating folate analogue, methotrexate in the isolation medium and further screened for folate production by growth in Folic Acid Casei Medium. Folate production was quantified using 3-aminophenol spectrophotometric method. Folate-producing lactic acid bacteria from fermenting maize slurry were species of Lactobacillus, Lactococcus, Pediococcus and Leuconostoc while yeast isolates were mainly species of Candida and Saccharomyces. However, Lactobacillus plantarum X13, Pediococcus pentosaceus L73, Candida parapsilosis Y77 and Candida tropicalis Y74 were used as starter cultures singly and in combination for the fermentation and production of ogi. The highest folate concentration, 30.97 ± 0.37 μg/ml, was observed after 24 h of the co-fermentation of maize slurry with Lactobacillus plantarum X13 and Candida tropicalis Y74. This represents a triple fold of the folate concentration observed in unfermented maize slurry. The pH of the fermenting maize slurry was observed to decrease from 6.12 to 3.60, while the reducing sugars and the titratable acidities were observed to increase as fermentation progressed. Sensory evaluation of the ogi samples after fermentation showed high general acceptability comparable to the naturally fermented ogi as regards to colour, taste, flavour, aroma and texture. The data made available in this study suggest the possibility of folate enrichment of ogi and its use as a vehicle for increasing folate availability to consumers thereby preventing folate deficiency diseases prevalent in many African countries.展开更多
本研究从重庆泡菜及扬州豆酱等传统发酵食品中筛选出3株具有优良产香能力的酵母菌,通过对其菌落形态特征、产酯能力、糖利用能力、面团发酵力以及高糖耐受能力等的测定,最终得到1株具有潜在应用价值的产香酵母YG28B,经ITS r DNA鉴定为...本研究从重庆泡菜及扬州豆酱等传统发酵食品中筛选出3株具有优良产香能力的酵母菌,通过对其菌落形态特征、产酯能力、糖利用能力、面团发酵力以及高糖耐受能力等的测定,最终得到1株具有潜在应用价值的产香酵母YG28B,经ITS r DNA鉴定为季也蒙毕赤酵母。在面包发酵与烘焙应用的初步研究中,YG28B与市售活性干酵母混合发酵烘焙的面包,其面团发酵效果良好,且烘焙的面包囊风味独特。气相色谱-质谱联用技术检测显示面包中挥发性风味物质含量普遍有所提高,优于单独使用市售活性干酵母发酵烘焙所得面包的风味。该株产香酵母菌可用于面包发酵以改善面包囊的风味,在烘焙制品中具有潜在的应用价值。展开更多
文摘This study was aimed at selecting starter cultures for bio-enriching ogi (fermented cereal gruel) using folate-producing microorganisms. The folate-producing microorganisms were isolated by incorporating folate analogue, methotrexate in the isolation medium and further screened for folate production by growth in Folic Acid Casei Medium. Folate production was quantified using 3-aminophenol spectrophotometric method. Folate-producing lactic acid bacteria from fermenting maize slurry were species of Lactobacillus, Lactococcus, Pediococcus and Leuconostoc while yeast isolates were mainly species of Candida and Saccharomyces. However, Lactobacillus plantarum X13, Pediococcus pentosaceus L73, Candida parapsilosis Y77 and Candida tropicalis Y74 were used as starter cultures singly and in combination for the fermentation and production of ogi. The highest folate concentration, 30.97 ± 0.37 μg/ml, was observed after 24 h of the co-fermentation of maize slurry with Lactobacillus plantarum X13 and Candida tropicalis Y74. This represents a triple fold of the folate concentration observed in unfermented maize slurry. The pH of the fermenting maize slurry was observed to decrease from 6.12 to 3.60, while the reducing sugars and the titratable acidities were observed to increase as fermentation progressed. Sensory evaluation of the ogi samples after fermentation showed high general acceptability comparable to the naturally fermented ogi as regards to colour, taste, flavour, aroma and texture. The data made available in this study suggest the possibility of folate enrichment of ogi and its use as a vehicle for increasing folate availability to consumers thereby preventing folate deficiency diseases prevalent in many African countries.
文摘本研究从重庆泡菜及扬州豆酱等传统发酵食品中筛选出3株具有优良产香能力的酵母菌,通过对其菌落形态特征、产酯能力、糖利用能力、面团发酵力以及高糖耐受能力等的测定,最终得到1株具有潜在应用价值的产香酵母YG28B,经ITS r DNA鉴定为季也蒙毕赤酵母。在面包发酵与烘焙应用的初步研究中,YG28B与市售活性干酵母混合发酵烘焙的面包,其面团发酵效果良好,且烘焙的面包囊风味独特。气相色谱-质谱联用技术检测显示面包中挥发性风味物质含量普遍有所提高,优于单独使用市售活性干酵母发酵烘焙所得面包的风味。该株产香酵母菌可用于面包发酵以改善面包囊的风味,在烘焙制品中具有潜在的应用价值。