GARLIC-GINGER AS POTENTIAL BIO-PRESERVATIVE IN FERMENTED MAIZE AND SORGHUM PASTES

Biopreservative Effects of Garlic and Ginger on fermented Maize and Sorghum pastes

Abstract

Garlic and ginger are natural spices with potentials as biopreservatives and allied health benefits. Fermented pastes either from maize or sorghum have a shelf life of fewer than 10 days except when refrigerated. In this study, garlic and ginger were added separately and in combinations to the fermented pastes prepared from maize and sorghum grains with a view to extending its shelf life resulted in 7 treatments. During storage for 4 weeks at ambient and refrigeration temperatures, the microbial load was enumerated and isolates identified using conventional methods. Physicochemical properties and shelf-life of the paste were also evaluated. Prominent in the fermented pastes during storage were 8 species of lactic acid bacteria and yeast (Saccharomyces cerevisiae and Saccharomyces rouxii). Garlic inhibited the growth of Candida utilis, Candida mycoderma, Candida tropicalis, Candida krusei, and Rhodotorula glutinis in paste during storage.  Bio-preserved paste using 4% garlic with 2% ginger had the best preservative effect on total viable counts (8.29-11.30 CFU/g), lactic acid bacteria (8.3-9.70 CFU/g) and yeast (4.69-9.45 CFU/g) counts. The study established that fermented pastes produced from either maize or sorghum can be effectively bio preserved using garlic, ginger, and garlic-ginger at 2 or 4 % for 4 weeks without spoilage at ambient temperature (27± 2^oC); thus, extending its shelf life.