Bacteriological Assessment and Proximate Analysis of Different Grades of Tomatoes Sold in Some Abuja Major Markets

Abstract

Tomato (Solanum lycopersicum) is a common vegetable sold in different grades (fresh and spoiled) and widely consumed in Nigeria. It has high water content, which makes it habitable for bacteria and predisposes it to spoilage by pathogenic organisms, thus posing significant health risks to consumers. In this study, the bacteriological quality and proximate analysis of different grades of tomatoes sold in five different markets in Abuja, Nigeria, were assessed. Fresh and spoiled tomatoes were bought and analyzed for the presence and count of bacteria using appropriate microbiological methods. The bacterial isolates were identified phenotypically and confirmed with molecular identification procedures. Higher bacteria counts (29-90 ⅹ 105 CFU/g) were recorded in spoiled tomatoes, and species of bacteria from different genera were identified. The bacteria include species of Corynebacterium, Staphylococcus, Pseudomonas, Enterobacter, Bacillus, Klebsiella and Serratia. Furthermore, there were marked variations in the values of proximate and vitamin analysis for the different grades of tomatoes analyzed. Vitamin A as well as crude lipid and fibre were lower with higher pH in spoiled tomato when compared to the fresh ones. The study concluded that improper handling during transportation and market exchange are major routes of contamination, which is predominantly observed in damaged tomatoes. Also, the high bacteria count, as well as the presence of some pathogenic organisms associated with the consumption of tomatoes, especially damaged ones, raises serious concerns about public health.