Ecology of Traditional Cereal Fermentation
M.U. Ukwuru*, A. Muritala, S. Ukpomwan
Department of Food Science and Technology, Federal Polytechnic, Idah, P.M.B. 1037, Idah, Kogi State, Nigeria.
Cereals are globally number one food crops as well as substrates for fermentation. Fermentation of cereal-based foods is a common practice in Africa. It is a desirable process of biochemical modification of primary food matrix brought about by microorganisms and their enzymes. Traditional food fermentations represent an extremely valuable cultural heritage in most regions and habour huge genetic potential of valuable but hitherto undiscovered strains. Microbial diversity of cereal-based fermented foods ranged from lactic acid bacteria to endospore-forming bacteria, amylolytic producing yeasts and filamentous moulds. Yeasts in cereal fermentation increases the protein content of fermented food products. The genus Saccharomyces, in particular Saccharomyces cerevisiae is strongly associated with the production of fermented cereal products for human Consumption.
The prominent group of bacteria with antifungal property is the lactic acid bacteria (LAB). LABs are large group of beneficial bacteria in the ecosystem of several fermentations as they have major potentials for use in biopreservation. Microorganisms engage in a wide variety of interactions. During the fermentation of sorghum, millet and maize, the pH of the medium decreased due to the production of carboxylic acid by fermenting microorganisms. Traditional food products arising from such fermentations include pito, ogi, burukutu, kunu-zaki etc. The predominant microorganisms for these fermentations are mainly LABs and yeast species. The ecological information helps to effectively manage the microbial growth and activities during fermentation.
Key words: Ecology, Cereal fermentations, Lactic acid bacteria, Yeasts, Cereal fermented food products.