Comparative Assessment of the Microbiological and Physicochemical Quality of a Laboratory Brewed ‘Burukutu’ and Commercialized Products Sold in Some Markets in Port Harcourt Nigeria

Abstract

Burukutu is an indigenous, brown coloured, cloudy, alcoholic beverage traditionally brewed using mainly sorghum grains. This study was aimed at the comparison of microbial quality, physicochemical properties, proximate composition and minerals content of laboratory brewed burukutu (LBB) and commercial products sold in some markets in Port Harcourt. Sixteen (16) samples of the commercialized product were evaluated from Elele (EM), Rumuokoro (RM) and Choba (CM) markets, Port Harcourt, Rivers State using Standard Methods while LBB was produced in our laboratory using Standard Procedures. Our result indicated an increase in aerobic mesophiles, total coliforms, faecal coliforms, fungi and lactic acid bacteria (LAB) counts during the early stages of the brewing process of laboratory produced burukutu but only LAB was detected in the final product. The overall microbial count of burukutu from the three markets revealed that CM>EM>RM although all the samples had higher microbial count compared with the LBB. Staphylococcus aureus, Escherichia coli, Lactobacillus sp., Lactobacillus sp., Aspergillus sp. and Saccharomyces cerevisiae were present during the brewing stages of burukutu. Enterobacter aerogenes and Mucor sp. were detected in the commercial samples purchased from the three markets. Lactobacillus fermentum and L. brevis had the highest and least frequency of occurrence in all the samples, respectively. The pH, titratable acidity, alcohol content and soluble solids of the fermenting LBB were within the range of 3.0-3.4, 0.6-0.97%, 3.0-4.7% and 0.98-0.99%, whereas in the commercialized samples, the equivalent values were 3.0-3.1, 0.00-0.10%, 2.1-4.0% and 0.65-0.82%, respectively. Moisture, crude fat, ash, crude protein and carbohydrate content of the commercialized samples were within the range of 29.1-31.2%, 10.8-14.2%, 3.8-4.85%, 2.9-5.7%, and 44.7-51.7% compared to the range of values obtained in the LBB (52.1%, 15.7%, 9.8%, 7.6% and 15.4%), respectively. The following minerals elements K, Ca, Na, Zn and Mg present in the LBB were higher than the values obtained in the commercialized alcoholic beverage. The results from this study, suggest that the quality of LBB is better than the commercialized products. Therefore, it is recommended that in order to improve the overall quality of commercially brewed burukutu for the benefit of everyone irrespective of social status, good manufacturing practices (GMP) and good hygienic practices (GHP) should be strictly adhered to by local producers and vendors.