Production of Vinegar from Oil-palm Wine Using Acetobacter Aceti Isolated from Rotten Banana Fruits

Abstract

Vinegar production using Acetobacter aceti isolated from ten rotten banana fruits collected from different vendors in Eke-Awka Market in Awka, Nigeria was carried out using cultural techniques, with glucose yeast calcium carbonate-ethanol agar as the growth medium. The mean viable count of the bacterial isolates was 0.72 x 10 2 cfu/g. The isolates were characterized on the basis of their morphological and biochemical characteristics and identified as Acetobacter aceti and Acetobacter orleanensis with mean counts of 0.53 X 10 2 cfu/g and 0.19 x 10 2 cfu/g respectively. Freshly-tapped oil-palm wine was allowed to ferment for seven days at 30℃. The alcohol content was 10.0% while the pH value was 4.6 on the seventh day of the fermentation. The fermented palm wine was further fermented with the Acetobacter aceti for four weeks producing vinegar containing 7.1% acetic acid with a pH value of 3.5. The Acetobacter aceti grew well in high concentration of alcohol indicating that it is suitable for large scale vinegar production. In addition, the rotten banana fruits regarded as wastes were converted into a useful raw material for the isolation of Acetobacter aceti needed for the production of acetic acid and vinegar.