Aerial yam (Dioscorea bulbifera) is one of the varieties of yam cultivated in Nigeria but less consumed. To diversify the processing methods and encourage its other uses, the yam was subjected to fermentation process for 5 days. The microbial, pH and titratable acidity (%TA) of the fermenting mash as well as the proximate composition of the fermented and unfermented flour were assessed. The total viable counts increased from 1.64 × 108 cfu/ml by day 3 and decreased to 7.62 × 102 cfu/ml at the end of fermentation. While the pH decreased, the TA increased at the end of fermentation. The prevalent microbial genera involved in the fermentation were Lactobacillus, Bacillus and Penicilium. The proximate composition of the fermented flour differed significantly (p<0.05) from the unfermented with increased protein content from 6.78g/100g (control) to 9.26g/100g. Fermentation improved the nutritional and microbial quality of aerial yam flour.
