Microbiological quality assessment of garri with reference to thermonuclease activity

Abstract

The microbiological quality of garri obtained from open markets and traditional processing industry in Benin City with reference to staphylococcal contamination was investigated. Enumeration of the total heterotrophic bacteria, total fungal propagules and Staphylococcus aureus in food samples was carried out using appropriate media. The staphylococcal thermonuclease activity determination was used as an indicator of previous (substantial) growth of S. aureus and possible presence of staphylococcal enterotoxins. The total heterotrophic bacterial count of the open markets’ samples was 7.75±2.87×10 3 cfu/g with corresponding staphylococcal count of 1.65±0.82×10 3 and fungal propagule count of 2.50±1.14×10 2 cfu/g. Samples obtained immediately after processing from the traditional garri industry revealed total heterotrophic bacterial count of 5.00×10 1 cfu/g; staphylococcal count of 5.00×10 0 cfu/g and no fungal count. The zone diameter of thermonuclease activity was 8.13±0.52 mm for open markets’ samples while traditional processing industry samples have 7.83±0.54 mm. From the study, it was found that there was contamination and growth of S. aureus and possibly the presence of staphylococcal enterotoxin in the product. The public health significance of the microorganisms with the production of thermonuclease and enterotoxins by S. aureus are discussed.