Microbiological quality of water processed and bottled in Zimbabwe.

A total of sixty samples of bottled water processed in Zimbabwe by three companies, were analysed microbiologically, to assess the relative safety of locally processed bottled water. The samples were from different batches and from different storage conditions and the analyses were for total viable counts and coliforms. Four (6.7%) and seven (11.7%) samples were found to exceed the recommended maximum total viable and coliform counts, respectively. There was a low incidence of Staphylococus aureus (3.3%), Pseudomonas species (6.7%) and Bacillus species (5%). Overall, the work shows that locally bottled water is generally safe, microbiologically, though it is necessary to continue with precautionary measures because any lapse in hygiene may lead to microbial proliferation.

Use of starter cultures containingStreptococcus diacetilactis, Lactobacillus brevis andSaccharomyces cerevisiae for fermenting milk for production of Nigeriannono.

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.

Glutamic acid production byBacillus isolates from Nigerian fermented vegetable proteins.

Twenty-fiveBacillus isolates comprising eight species fromdaddawa, daddawansoya, oglrl, okplhe andugba (all Nigerian fermented plant proteins) all produced glutamic acid in varying concentrations when grown in a basal medium. Glutamic acid release during the course of termentation indaddawa showed a corresponding release pattern by the fermentingBacillus subtilis isolate in the basal medium.

Heat-resistant Fungi in Soil Samples from Northern Nigeria.

A total of 156 soil samples collected from parts of Northern Nigeria were examined for heat-resistant fungi (HRF) which could cause spoilage of heat processed fruits and fruit products. Each sample was subjected to 70°C for 1 h before plating on potato sucrose agar. Approximately 77% of all the samples contained HRF which were identified as Neosartorya fischeri , N. fischeri var. spinosus , N. quadricincta and Aspergillus fischeri . Other HRF which occurred infrequently were Aspergillus fumigatus and Penicillium spp. The fungal counts in the positive samples generally ranged from 18-300 propagules/10g of soil.