Microbiology and quality assessment of ‘burukutu’ a Nigerian fermented alcoholic beverage

Abstract

Burukutu is an indigenous alcoholic beverage made in Nigeria from guinea corn. Microbial quality of the brewed burukutu was investigated using standard spread plate method. Ten samples of commercially prepared burukutu were aseptically collected in 500 ml sterile bottles in triplicate from ten randomly selected brew houses in Army barracks and Angwan kaje, Minna, Niger State, Nigeria. The total viable counts, coliform count, and fungal count ranged from 6.7x109 cfu/ml – 7.9x109 cfu/ml, 1.6x106 cfu/ml – 2.6x106 cfu/ml and 2.3x108 cfu/ml – 1.54x108 cfu/ml respectively for all locations samled. The microorganisms isolated from commercially produced burukutu are Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Aspergillus niger, Aspergillus flavus and species of Enterobacter, Klebsiella, Saccharomyces, Streptococcus, and Fusarium, Staphylococcus aureus, and Bacillus subtilis were isolated from burukutu prepared in the laboratory. The proximate analysis revealed that pH values ranged from 3.0 – 3.9 temperatur ranged from 27.20 – 29.00 titratable acidity ranged from 0.14 – 0.16 alcoholic content ranged from 1.8 – 3.6%, dry matter content ranged from 3.6-8.0% ash content ranged 0.16-0.36% and crude protein content ranged from 3.18-3.29%. While the minral analysis revealed that magnesium content of the samples ranged from 119.30-1073.61ppm. Laboratory prepared burukutu was found to contain the highest calcium (3532.10ppm) and the lowest (917.28ppm) was found in burukutu from Angwan Kaje. The iron content of the samples ranged from 76.00-113.20ppm. The data obtained from proximate and mineral analysis were subjected to a one-way analysis of variance which showed that there were no significant difference in levels of crude protein, ash content, temperature, magnesium and iron. While there were significant difference in levels of pH, total titratable acidity, dry matter content, alcohol content and calcium analysed. Consumption of burukutu may pose a public health hazard because of reported abilities of some fungi isolated to produce mycotoxin. There is therefore need for training local brewers on basic hygiene and measure to reduce risk of contamination by microorganisms.