| dc.description.abstract | Tomato (Lycopersicon esculentum) is one of the rich sources of antioxidants, for example,
phenols, which are known to be associated with decreased risks of chronic diseases. However,
cooking influences the antioxidant properties of vegetables. Therefore, this study aimed to
determine the extent of the effect of two common local cooking methods of Ugandan people
(boiling and frying) on the antioxidant properties of tomato; specifically on the quantity of
selected phytochemicals with antioxidant properties, in this case phenols, and the free radical
scavenging activity of the tomatoes. Tomatoes were bought from Kalerwe market and blended
to form a paste which was subjected to the preparations (cooking and frying) and later used
after extraction. The extraction was done using distilled water and 70% ethanol. The
subsequent extracts were used in the determination of total phenolic content using the FolinCiocalteau
method and free radical scavenging activity using the DPPH free radical scavenging
assay. Results indicated significant differences (p value<0.0001) in the total phenolic content
of the fresh, cooked and fried extracts for both the aqueous and ethanolic solvents with the
fresh extract having the highest total phenolic content followed by the boiled extract then the
fried extract having the lowest. The differences were also seen in the free radical scavenging
activity with the fresh extract having the lowest mean inhibitory concentration indicating it had
the highest free radical scavenging activity followed by the boiled extract and then the fried
extract which had the highest mean inhibitory concentration indicating it had the lowest free
radical scavenging activity. Consequently, the antioxidant activity of cooked tomato fruit
depended on the way, the time and/or the temperature of the cooking process; boiling and frying
caused significant changes in the antioxidant properties of tomatoes therefore consumers are
advised to consume fresh tomatoes. However, among the two methods evaluated, boiling was
a better method than frying to retain antioxidant properties in tomatoes. Further studies should
be carried out to investigate the effect of cooking on the in-vivo antioxidant properties of
tomatoes | en_US |
