RESUMO
The maize value chain in the Kogi State and most parts of the country from where maize is purchased into the State lacks mechanisms that ensure grain quality and safety. Against the above-backdrop, this study was designed to evaluate toxigenic fungi and associated mycotoxins in maize produced within different agro-zones of Kogi State. Harvested and stored maize seeds under different storage conditions were collected from three different zones (Zone B Bassa, Zone C Lokoja, and Zone D Idah) and cultured. Different fungal species were isolated by culturing using the spread plate technique on potato dextrose agar (PDA) and identified microscopically. Mycotoxin production by isolated fungi was subsequently evaluated for Deoxynivalenol (DON) contamination using the High-Performance Liquid Chromatography technique (HPLC). The outcome of the study was statistically analysed using simple frequencies and percentages. Aspergillus spp. and Penicillium spp. were the fungi found to be associated with the stored seeds in Kogi, while Fusarium spp. Mucor spp. and Rhizopus spp. were the field fungi identified. Of the thirteen samples collected, the most common genera were Aspergillus (isolated from 41.67% of the evaluated samples), Fusarium (27%) and in a lesser extent Rhizopus spp. (8.33%). The result also shows DON was detected in 92.3% of the stored maize samples, making it one of the widespread mycotoxin contaminants of maize grain. Implications of this study for human and animal health and economic development were discussed and appropriate recommendations made especially for adoption of proper storage technology among small-scale farmers for improved maize quality and safety.
RESUMO
Millet grains were steeped in 1% sodium metabisulphite (1:2w/v) for 5min and subsequently washed and wet milled; the cereal paste was gelatinized with boiling water (1:1w/v, 76±2oC) and immediately hydrolyzed separately either with α+β-amylases, α+amyloglucosidase or rice malt. The hydrolyzed cereal starch was inoculated with a 12h starter culture (2%v/w) of Lactobacillus plantarum, L. fermentum, and Lactococcus lactis and fermented for 6h. Chemical (pH, titratable acidity), physical (viscosity, S.G., total soluble solids) and sensory quality of the hydrolyzed cereal slurry and the fermented product were determined. The results obtained in this study show that the pH of the products decreased with concomitant increases in titratable acidity (% lactic acid) during production; however, the decrease in pH was more prominent in the ‘kunun-zaki’ produced from the cereal starch treated with α+β-amylases and this, differed from the other products (p<0.05). There was an increase in viscosity with a corresponding decrease in the total soluble solids (TSS) in all the samples throughout production; the decrease in TSS is an indication of an increase in the activity of the fermenting LABs. Furthermore, the sensory quality attributes of the three products were generally acceptable by the taste panelist in all the parameters evaluated (appearance, aroma, taste), however, the ‘kunun-zaki’ produced using the cereal starch treated with rice malt was preferred in taste and this was significantly different (p<0.05) from the other products. This study has shown that ‘kunun-zaki’ of acceptable quality could be produced within 7h, the marked reduction in the processing time of ‘kunun-zaki’ from 12-7h could encourage large-scale production of this popular drink.