The Role of Microorganisms in The Nutrient Improvement of Urea Fermented Brewer’s Dried Grains

Abstract

The role of microorganisms in the improvement of the nutritive value of urea fermented brewer’s dried grains (BDG) was investigated.  One kilogramme of BDG was weighed into two containers each and thoroughly mixed with 1% and 2% urea solutions, put into two thick black polythene bags, sealed and stored under shade to ferment for 7 days. Wet samples of the 1% and 2% urea fermented BDG were used for microbial identification and population count by microscopy and culture test methods. Proximate and detergent fibre compositions showed significant (P < 0.05) improvement in the crude protein content of urea fermented BDG. The crude fibre contents were significantly (P < 0.05) decreased with increased urea concentration. The fibre fractions of urea fermented BDG were significantly (P < 0.05) reduced. Bacteria organisms were identified and found to be responsible for fibre breakdown in urea fermented BDG. Improved crude protein contents resulted from fibre breakdown by bacteria and the bacteria proteins.

Keywords: Urea, Fermentation, Concentration, Brewer’s dried grains, Nutritive value, Microorganisms