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Processing and Bioavailability (WG2) page 19
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5 Storage of finished products O
D
Survey of references:
O use of barrier packaging
D avoid high storage temperature
Some research works deal with the effects of storage on the stability of tomato
antioxidant components: most of these studies concern dried tomatoes. This is principally due
to the fact that dried tomato products are very sensitive to colour fading, and this effect is
mostly due to lycopene isomerisation and oxidation and to non-enzymatic browning.
The tests carried out by Zanetti (1997) on industrially produced diced tomato lead to
conclusions which are not always easy to explain: They yield a sizeable lycopene reduction
only in the product packaged in raw tinplate cans (- 27% after 400 days), and a less noticeable
reduction in the product packaged in glass bottles (- 13%)
In their study on foam-mat-dried tomato powder, Lovric et al. (1970) made some
fundamental observations on the mechanism of lycopene degradation during the storage of
dehydrated products. The percent retention of lycopene at various temperatures at high
temperatures and in the presence of oxygen and/or nitrogen are shown in Table 3. The main
conclusions of this study were the following. With regard to colour stability, a much faster
colour loss occurred in the presence of air. The predominating mechanism of colour fading is
autoxidation of lycopene. The extreme desiccation achieved with in-package desiccant (