Bacterial contaminants in lettuce, tomatoes, beef and goat meat from the Accra Metropolis

Abstract

A survey on the role of lettuce. tomatoes, beef and goat meat in the transmission of food-borne bacteria in Accra was conducted by evaluating their microbial quality. All 60 market lettuce samples had significantly higher faecal bacteria compared to 8(12%) from the farms (5.0 ± 09 vrs. 4.3 ± 0.9. p <0.001). Salmonella Groups D and G, Shigella dysenteriae, flexneria and boydii were detected in both farm and market samples. Irrigation with tap water instead of drain water significantly reduced the level of faecal coliforms (4.4 ± 0.9 vrs. 3.8 ± 0.7, P <0.00 I). Market (16) and farm (8) samples of tomatoes had similar levels of coliforms and faecal coliforms but rotten tomatoes had more coliforms (6.8 ± 0.37 vrs. 4.6 ± 0.65, p<0.001) and faecal coliforms (4.7 ± 0.29 vrs. 3.5 ± 0.81, p<O.OO I) than whole tomatoes. Salmonella Group B was isolated from one farm sample. Mesophilic counts of beef from the abattoir were within acceptable limits of less than 7.0 log10 cfu/g. Market samples had significantly higher coliforms (5.0 ± 0.62 vrs. 3.5 ± 1.8, p<O.05) than the abattoir samples. Salmonella Group B and Shigella dysenreriae were isolated from beef from the market. Coliforms and faecal coliforms were numerically Higher In the market and supermarket samples of goat meal. Shigella flexneri was isolated from only the supermarket samples. Vegetables and meat available in the Accra Metropolis could be sources of food-borne bacteria. Predisposing factors and strategies to improve their hygienic quality are discussed.