ABSTRACT

This study evaluated the Thiamine and Riboflavin concentrations in fermented maize using lactic acid bacteria. A total of four (4) different species of Lactic acid bacteria were isolated from the nunu milk samples using biochemical identification, Gram staining, outcomes of microscopic analysis and carbohydrate fermentation pattern. The total lactic acid bacteria count observed in this study ranged from 4.7×10⁴cfu/ml to 5.4 ×10⁴cfu/ml with sample B4 giving the highest count of 5.4 ×10⁴cfu/ml whereas sample B1 had the lowest lactic acid bacterial count of 4.7×10⁴cfu/ml. The results on assimilation of different carbon sources revealed that all lactic acid bacterial isolates can assimilate different carbon sources like glucose, dextrose, sucrose, fructose and lactose. The Thiamine (vitamin B1) concentration in the fermenting maize recorded 0.016mg/ml at the beginning of fermentation (steeping period), then increased to 0.025mg/ml at the end of the fermentation. In the same sequence, The Riboflavin (vitamin B2) concentration in the fermenting maize recorded 0.0033mg/ml at the beginning of fermentation (steeping period), then increased to 0.065mg/ml at the end of the fermentation process. Thiamine and Riboflavin quantification of the fermenting maize slurry showed that lactic acid bacteria isolates were responsible for Thiamine and Riboflavin production in the fermenting slurry as there was an increase in the Thiamine and Riboflavin concentrations of the slurry. From the result obtained, it can be concluded that vitamin-producing lactic acid bacteria can be used as a cost-effective alternative to current vitamin fortification programmes and for the elaboration of novel vitamin-enriched cereals products. Increasing levels of B-group vitamins in fermented cereals are possible through the selection of microbial species and implementation of fermentation conditions. Different strategies may be applied to improve microbial production of vitamins in cereals fermented products. These strategies include (1) selection of natural overproducers using chemicals, (2) strains selection whitin culture collections, (3) increasing vitamins bioavailability and (4) use of genetically modified LAB (GM-LAB).