Isolation and Characterization of Lactic Acid Bacteria Involved In the Fermentation of Millet and Sorgum Sold In Nkwo-Achara Market, Abia State

Abstract

The isolation and characterization of lactic acid bacteria responsible for the fermentation of kunu-zaki and burukutu were studied in order to access their use as starter culture. Representatives of the lactic acid bacteria were isolated at 12hours interval during the course of fermentation characterized and identified using morphological, physiological and biochemical examination. Changes in pH, titratable acidity, LAB counts were also investigated during the fermentation of the two cereals at different fermentation time (12hrs and 24hrs). The isolates obtained were accessed to have some level of starter culture. Based on the comparative performance of single isolates to a substrate and pH reduction. Isolates identified are lactobacillus plantarum, lactobacillus cellobiosus, lactobacillus pentosus, leuconostoc mesenteriods, and pediococcus pentosaceus. Results indicates a predominance of lactobacilli among isolates. Lactic acid bacterial counts in the kunu-zaki and burukutu were isolated at levels of 10 6 , 10 7 , cfu/ml. A very high reduction in pH was associated with an increase in titratable acidity. Analysis of variance show significance difference between pH of all the isolates in the two substrates used at P < 0.05% of freedom.