Microbiological examination was performed on a batch of fruit-fiavoured bottled water, which had spoiled, to determine the causal organism. The product had spoiled on storage at ambient temperature following routine production. The spoiled product was turbid (equating to a MacFarland no. 5) and had a characteristic sour odour, suggesting the presence of an acetic acid bacterium. Quantitative microbiological examination on MRS Agar (Oxoid CM361, Oxoid Ltd., England) incubated aerobically at 20 deg C for 48 h demonstrated the presence of a pure culture (> 10~6 ml~(-1)). The colonies were small and translucent with a pinkish hue. In addition, they were shiny and smooth and were raised with an entire margin. Given the relative difficulty in the phenotypic identification of the acetic acid bacteria, the isolate was identified by employment of molecular techniques, namely PCR amplification and direct sequencing of a region of the organism 16S rRNA gene.
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