Abstract-The production of bio-ethanol from corn is a mature technology that is not likely to see significant reduction in the production costs. Substantial cost reductions may be possible if cellulose based agricultural wastes such as corn cobs are used instead of corn. In this study, corn cobs which are in abundance and do not interfere with food security was subjected to simultaneous saccharification and fermentation process by co-culture of Aspergillus niger and Saccharomyces cerevisiae for 7 days. The corn cobs were sundried, milled into powder using hammer milling and stored at room temperature (25 O C) before use. The growth media used for culturing Aspergilus niger and Saccharomyces cerevisiae inocula were prepared respectively. Parameters such as biomass yield, cell dry weight, reducing sugar concentration, pH of the fermentation medium and the ethanol yield were determined at 24 hours intervals. The results of the study revealed that the yeast and mould biomass yield obtained from the corn cobs on the 7 th day was 0.59 (OD), while the microbial cell dry weight obtained on the same day was 0.88mg/cm 3 . The substrate was hydrolyzed to produce 0.63mg/cm 3 reducing sugar concentrations. The pH values of the fermentation medium varied between 3.05 and 7.58. Optimal ethanol yield of 10.08v/v was obtained after 7 days of fermentation. The results of this study suggest that agricultural wastes that contain fermentable sugars can no longer be discarded into our environment, but should be converted to useful products like bio-ethanol.

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Human vitamin deficiencies still occur in many countries although most vitamins are present in a variety of foods, mainly because of malnutrition not only as a result of insufficient food intake but also because of unbalanced diets; this work screens some Lactic acid bacteria isolated from selected Nigerian fermented foods for vitamin (thiamine, riboflavin and niacin) production. Five lactic acid bacteria were isolated from selected Nigerian fermented foods (yoghurt, ogi, ogiri, ugba). The isolated lactic acid bacteria were identified based on cultural and biochemical characteristics. All the isolates were screened for thiamine, riboflavin and niacin production using microbiological assay. Thiamine, riboflavin and niacin produced were quantified.

In the quest to produce an acceptable local beverage that could serve as an alternative variety to kunun-zaki for many millions of Nigerians who take the cereal-based beverage as their most preferred and affordable drink a study was undertaken to assess the microbial and sensory quality attributes of laboratory-produced Date fruit-based kunun-zaki. Different blends of dry date fruits (Phoenix dactylifera) and sorghum (Sorghum bicolor) formulated as follows; F1 (100:0), F2 (70:30), F3 (50:50), and F4 (30:70%) of date fruits/sorghum were soaked overnight in water, drained and were wet-milled with ginger and cloves using an equal volume of sterile water, F5 (0:100) was market (Control) sample. The microbial succession study included the identification of organisms at various critical stages of the production of the beverage. The results of the study showed the mean pH, and TTA (%) values for the respective formulated Kunun-dabino product were F1 (4.87 and 0.3870), F2 (4.66 and 0.4508), F3 (4.29 and 0.4600), F4 (4.04 and 0.4690), F5/Control (4.32 and 0.4589) respectively. The mean Total bacterial, coliform and fungal loads of the four experimental products were 2.58 x 104, NIL, and 3.56 x 103 CFU/ml respectively which fall within W.H.O’s recommended standards for ready-to-eat foods. Species of Bacillus, Enterobacter, Shigella, Lactobacillus, Aspergillus, Penicillium Mucur, and Candida were present at the initial production stage while Bacillus and Lactobacillus species persisted right through to the final stage of production. The results of the sensory evaluation showed that while F1 was the least liked, F3 was significantly preferred over the other samples (P < 0.05). The study has shown that ‘Kunun dabino’ produced under the laboratory conditions in this study provides a new brand of beverage that is both microbiologically safe and organoleptically more acceptable to taste panelists.

Background:The high cost of conventional animal feed ingredients in Nigeria has made it necessary to search for alternative local sources of feed. Crop residues including sweet potato leaves abound in Nigeria. These have been explored as feed sources. The ability of microorganisms to convert agricultural wastes to more useful products could be harnessed to produce feed from sweet potato leaves which can be obtained in high abundance at low cost. Aim: To examine the possibility of converting sweet potato leaves to animal feed through fermentation with a co-culture of Chaetomium globosum and Saccharomyces cerevisiae. Materials and Methods: Triplicate samples of sweet potato leaves were fermented with a coculture of C. globosum and S. cerevisiae for 21 days at 25±2°C and the effects of fermentatio n on Original Research Article nutrient composition were determined. Fermentation and control samples were analysed for proximate, amino acids, and elemental contents. Results: Crude protein, crude fat and ash contents increased by 97.5%, 265.3% and 12.3%, respectively, while crude fibre and nitrogen free extract values decreased by 22.7% and 61.4% respectively. Energy content increased by 14.5%. The observed changes in the values of these nutritional components were significant (P = 0.05). The percentage dry matter values of all the amino acids analyzed (lysine, histidine, arginine, aspartic acid, threonine, glutamic acid, proline, glycine, alanine, cystine, valine, methionine, isoleucine, leucine tyrosine and phenylalanine) were found to increase, with the contents of seven of the amino acids increasing significantly. Calcium, phosphorus, potassium and magnesium contents increased significantly while those of copper and iron decreased. Conclusion: Fermentation of sweet potato leaves with a co-culture of C. globosum and S. cerevisiae enhanced the feed potential of the leaves. With mineral supplementation, energy enhancement, and further crude fibre reduction, fermented sweet potato leaves could serve as feed for some animals.