ASSESSMENT OF A BACTERIOCIN-PRODUCING LACTOBACILLUS STRAIN IN THE CONTROL OF SPOILAGE OF A CEREAL-BASED AFRICAN FERMENTED FOOD

As part of a program to develop starter cultures aiding in the spoilag e control and sanitation of African fermented foods, a cereal-based fo od ('ogi' and its solid form 'agidi' or 'eko') was prepared using a ba cteriocin-producing Lactobacillus strain as the starter culture. The s urvival of an enterotoxigenic Escherichia coli strain was investigated in the naturally fermented food and in food fermented with the starte r bacteriocin-producing Lactobacillus strain. An inhibition of E. coli was observed within 2 h of incubation in 'ogi' fermented with the bac teriocin producing strain. After 6 h, the viable count of E. coli in l ocally fermented 'ogi' was log 6.41 (254 x 10(6) CFU/mL), whereas in ' ogi' fermented with the bacteriocin producer it was reduced to log 1.7 0 (0.5 x 10(2) CFU/mL). Comparison of the shelf life of 'agidi' prepar ed from the naturally fermented food with that fermented with the bact eriocin-producing starter culture showed that the latter had a better shelf life (kept for 11 d before spoilage occurred as compared with 7 d for the natural one). The results are discussed in terms of the pote ntial of bacteriocin-producing cultures in the control and retardation of spoilage and food-forne infections in some African fermented foods .