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Water is one of the indispensable resources for the continued existence of all living things including man. Government has failed to adequately provide safe, pipe-borne water for the increasing population in Nigeria and this has encouraged the sale of drinking water by private enterprises that have little knowledge about good manufacturing practices. This study investigated the bacteriological quality of commercial sachet-packed drinking water at point-of-sale in southwestern Nigeria with emphasis on pathogenic bacteria in 108 samples tested, in order to evaluate the contribution of this popular product to the increasing incidence of typhoid fever and related illnesses. Tenfold serial dilution of water samples and the pour plate technique were used to investigate the presence of Salmonella and indicator coliform Escherichia coli in sachet-packed water samples. Aerobic and total coliforms were also enumerated. Characterization of isolates was by in-vitro cultural, morphological and biochemical characteristics. Results showed that 87% of the sachet-packed water samples examined contained Salmonella and/or Escherichia coli, indicative of fecal contamination and inadequate water treatment or no treatment at all. The study also showed that about 65% of the polythene sachets used was not of food-grade quality and imparted polyester taste in the water samples. High aerobic colony counts in the order of 6.0 log CFU/ml was recorded from 93% of water samples examined. E. coli counts used as indicator of hygiene criteria were present in the range of 98 and 106 cfu/100ml of water sample, while Salmonella counts used as food safety criteria were between 2.12x10 1 and 2.20x10 1. These mean values were greater than the international guidelines for drinking water quality. The findings of this study indicate that sachet-packed water samples examined do not meet microbiological standards for drinking water quality. National surveillance agencies need to monitor and enforce compliance with microbiological safety standards of sachet-packed water being sold to the public.

Maize was cofermented with pigeon pea for ogi production and evaluated for nutritional (proximate composition, minerals, vitamins, and amino acid profile analyses) and antinutritional (phytate, tannin, and trypsin inhibitor activity analyses) qualities. White maize and pigeon pea were mixed at ratios of 90:10, 80:20, 70:30, 60:40, and 50:50, respectively, with 100:0 serving as the control. Mixtures were cofermented for 96 hr at 27°C ± 2°C and nutritional, mineral, and antinutritional qualities were analyzed using analysis of variance. Results of proximate analysis showed that the values were significantly difference at p ≤ .05. Maize cofermented with pigeon pea at a ratio of 60:40 had the highest protein (22.79 mg/100 g), fat (19.27 mg/100 g), ash (2.98 mg/100 g), crude fiber (0.73 mg/100 g), and lowest moisture (1.98 mg/100 g) content, and was significantly (p ≤ .05) different from the other ratios. Of all the mixtures analyzed, 60:40 was significantly (p ≤ .05) different and had the highest Vitamin B1, B2, and B3 contents. Amino acid profile results showed that maize cofermented with pigeon pea at a ratio of 60:40 showed the highest contents of lysine (93.95 mg/g), tryptophan (20.38 mg/g), isoleucine (54.78 mg/g), phenylalanine (86.23 mg/g), leucine (109.55 mg/g), and valine (68.29 mg/g), respectively, and was significantly (p ≤ .05) different from the other ratios. Results of antinutritional analysis showed low phytate, tannin, and trypsin inhibitor values in maize cofermented with pigeon pea at a ratio of 60:40 when compared with other ratios. The cofermented maize‐pigeon pea product 60:40 had high amino acid profile than the others.

The study investigated the incidence of Listeria monocytogenes in ready‐to‐eat (RTE) vegetables: (Cucumber, Cucumis sativas; Cabbage, Brassica olerecea; Carrot, Daucus carota; Tomato, Solanum lycopersicum; Lettuce, Lactuca sativa) in six states in South‐Western Nigeria. A total of 555 composite samples were collected from 30 traditional markets within the states and only 244 L. monocytogenes species were isolated by standard methods. The incidence of L. monocytogenes was low and not statistically significant per vegetable type. The percentage distribution of the L. monocytogenes isolates in the RTE vegetables was 28.28, 9.02, 23.36, 19.67, and 19.67 for Cabbage, Carrot, Cucumber, Lettuce, and Tomatoes, respectively. Lagos state had the highest incidence of L. monocytogenes contamination (55%) followed by Ondo (48.89%), Oyo (48.75%), Ogun (44.09%), Osun (34.38%), and Ekiti (33.33%) states, respectively. Although the incidence of L. monocytogenes in the RTE vegetables in South‐Western Nigeria is low, its presence should be a source of concern as it could constitute a public health threat for its consumers.

The anti-bacterial properties of aqueous and ethanol extracts of the calyces of Hibiscus sabdariffa on five bacteria genera, namely, Escherichia coli, Staphylococcus aureus, Salmonella typhi, Shigella dysenteriae and Streptococcus mutans were evaluated using agar well and disc diffusion methods. Six bioactive compounds were identified from phytochemical analysis of the juice extract of H. sabdariffa. Analysis revealed the presence of the following in the water and ethanol extracts: saponins (1.46%), alkaloids (0.09%), tannins (0.19%), total phenols (0.07%), flavonoids (2.41%) and glycosides (0.13%). The results revealed that both water and ethanol extracts had significant anti-bacterial effects (P ≤ 0.05) against the tested pathogenic bacteria genera with the ethanol extract of Roselle having higher antibacterial effects against all the pathogens. S. aureus and E. coli were the most sensitive to Roselle juice extract (47.9 and 45. 8 mm zones of inhibition, respectively). The minimum inhibitory concentration (MIC) for the ethanol extract of H. sabdariffa was between 0.26 and 1.03 mg/ml. The results observed in this study contribute to scientific baseline data on the anti-bacterial activities of H. sabdariffa juice extract.

Maize was cofermented with pigeon pea for ogi production and evaluated for microbiological qualities. White maize and pigeon pea were mixed at ratios of 90:10, 80:20, 70:30, 60:40, and 50:50, respectively, with 100:0 serving as the control. Mixtures were cofermented for 96 h at 27 ± 2°C, and microbiological and sensory qualities analyzed were carried out using analysis of variance. Values were significant at p ≤ .05. Results showed that there was a gradual decrease in the pH and increase in total titratable acidity (TTA), respectively, during fermentation in all the samples. At the end of fermentation, pH ranged from 3.47 to 4.27 and TTA ranged from 0.47% to 0.54%, respectively. Total heterotrophic count (THPC) ranged from 5.76 to 5.90 log cfu/g; lactic acid bacteria (LAB) from 6.15 to 5.98 log cfu/g; and yeasts from 5.51 to 5.79 log cfu/g. Microorganisms isolated were lactic acid bacteria (Lactobacillus buchneri, L. casei, L. pentosus, Pediococcus pentosaceus), yeasts (Saccharomyces cerevisiae, Candida kefyr, C. krusei, C. tropicalis), molds (Aspergillus niger, A. flavus, Penicillium oxalicum, Mucor racemosus and Rhizopus stolonifer) and other aerobic bacteria (Klebsiella oxytoca, Enterobacter amnigenus, Staphylococcus xylosus, Bacillus subtilis, B. firmus, Corynebacterium kutscheri, C. striatum, and C. afermentans). In conclusion, the total heterotrophic plate count (THPC) in fortified maize: pigeon pea products was very high. This could constitute health hazards to infants as weaning foods. However, the microbial loads could be reduced through heat treatment as ogi is usually boiled or treated with boiled water before consumption and it can therefore be concluded that the fortified maize: pigeon pea products could be used as weaning foods.

Starter cultures consisting ofStreptococcus diacetilactis, Strept. cremoris, Lactobacillus brevis andSaccharomyces cerevisiae were tested singly and in mixtures for ability to ferment milk to producenono with organoleptically acceptable qualities. Only mixed cultures containing eitherStrept. diacetilactis orStrept. cremoris andL. brevis were suitable. Presence of yeast adversely affected either acid formation or diacetyl production.Nono containingStrept. diacetilactis was acceptable, even in the presence ofSacch. cerevisiae, because of the high diacetyl production. A mixed starter containing two of these organisms,Strept. diacetilactis orStrept. cremoris andL. brevis, is recommended fornono production.Sacch. cerevisiae is not essential.

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