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Consumption of Spoiled tomatoes, beware of harmful microbial contamination -KNUST research

Thu 5 Aug 2021
Consumption of Spoiled tomatoes i

Consumption of spoiled tomatoes is on the increase with more patronage by some commercial food operators in Ghana.

Spoiled tomatoes may have higher nutritional and healthful plant-based chemicals than fresh tomatoes but highly contaminated with harmful microbes, thus not safe for consumption.

That is the conclusion of a study by the Kwame Nkrumah University of Science and Technology (KNUST), Kumasi with sponsorship from the Foundation for Food and Agriculture Research and Rockefeller Foundation

Consumption of tomatoes provides health benefits. However, they’re highly perishable due to their high moisture content, soft nature, postharvest handling and are highly prone to microbial contamination.

The study was undertaken to determine the nutritional and phytochemical compositions of fresh and spoiled tomatoes. The researchers also sought to determine the levels of microbial load in sampled tomatoes.

For the study, fresh tomatoes and spoiled tomatoes were obtained from different tomato sellers at Borla Market in Kumasi in the Ashanti region of Ghana and analysed.


The researchers found all the spoiled tomatoes had considerably higher levels of nutrients (crude fibre, higher potassium, high folic acid) as compared to the fresh tomatoes except for moisture and vitamin C.

Again, higher levels of plant-based chemicals known as phytochemicals were found in the spoiled tomatoes, particularly lycopene, beta carotene and chlorogenic acid.

The researchers attribute the results to advance ripening and moisture loss in spoiled tomatoes.

“As ripening goes on these phytonutrients are synthesized,” Lead scientist, Prof. Faustina Dufie Wireko-Manu said.

The researchers however warn spoiled tomatoes are highly contaminated with harmful microbes.

“We found the spoiled tomatoes were contaminated with molds, E. coli and other harmful bacteria, beyond recommended levels by Foods and Drugs Authority (FDA). They’re highly contaminated with microbes and therefore not safe for human consumption,”according to lead scientist, Prof. Faustina Dufie Wireko-Manu of the KNUST Food Science and Technology Department .