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Composition of tomatoes and tomato products in antioxidants (WG1) page 10
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The quality of a product can also be related to its composition in antioxidants. Thus,
with tomatoes, the stability of the processed products, the nutritional value, the colour
retention, the organoleptic qualities could be changed as a function of β-carotene, lycopene,
flavonoids and vitamin C contents. Further insight into the antioxidant composition of
tomatoes and the factors likely to modify this composition should help to better define the
quality of tomatoes, to evaluate the intake of each antioxidant of humans and to assess the
potential interactions among each of them during nutrition and public health studies. Such
investigation would also contribute to improve information available to breeding and
biotechnology companies, processing industries, health institutes and consumers.
2. Objectives
Our working group focused on the data collection of antioxidant composition in
tomato and tomato products. A first database contains average values of all antioxidants we
have found in literature. The antioxidant levels were reported for fresh tomatoes, but only few
papers have reported values for specific varieties. So, information has been collected about
the tomato varieties mainly used for the processing industry, and the concentrations of
carotenoids and vitamin C have been collected in a second database.
Beside fruit ripening, there are a number of factors that influence taste, colour and
antioxidant levels in tomato products. The effects related to tomato processing are reported by
the working group two.
Different strategies can be applied in order to improve or to modulate the tomato
quality and especially the carotenoid and ascorbic acid levels. Biosynthesis pathways of these
compounds are described with a specific attention on the genes and enzymes involved in the
metabolic steps. Breeding selection and biotechnology approach are presented.
The fruit colour and the antioxidant levels can progress during ripening. Cultural
practices can also modulate both parameters. Thus, influences of cultural practices and
ripening are described in this report.