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Processing and Bioavailability (WG2) page 36
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It is quite clear that any industrial transformation will exert a demolitive action on the
cells of the fruit; since lycopene is in the state of lipophilic coagulation, it is more readily
solubilised by the lipids taken up in a varied diet and thus is in a condition to be more easily
assimilated. Lycopene availability from tomato-based food is significantly higher than from
fresh tomatoes when co-ingested with oil. Ingestion of tomato juice cooked in an oil medium
resulted in a two- to threefold increase in lycopene serum concentrations 1 day after ingestion,
but an equivalent consumption of unprocessed tomato juice caused no rise in plasma
concentration (Stahl and Sies, 1992b). This indicated that heat treatment and an oil medium
are required to extract lycopene into the lipophilic phase. It was assumed that heating tomato
juice in the presence of corn oil for 1 h converts lycopene from the trans to the cis form,
thereby increasing its absorption by the body (Stahl and Sies, 1992a).
The food matrix (i.e., the lipid and other constituents of chromoplasts as well as the fibre
contained within the tomato fruits) may contribute greatly to the stability of the all-trans form
of lycopene in the fruits. This is supported by the observation that when whole tomatoes are
heat processed, no isomerization is noted. For example, tomato sauce and tomato paste
contain about 90% trans-isomers (Nguyen and Schwartz, 1998). The food matrix that
surrounds lycopene when it is present within the tomato seems to prevent this isomeric
equilibrium from occurring.
Lycopene is more easely extracted from cooked meals than raw material, where it is
bound to the matrix. Thermal processing such as cooking and mechanical cell disruption such
as chopping are convenient ways to enhance availability by breaking down sturdy cell wall
structures, disrupting chromoplast membranes, and reducing cellular integrity, thus making
lycopene more accessible (Fig. 4).
Is this step an RCPL ?
This paragraph includes aspects which vary widely and which cannot be grouped
together, hence a hazard analysis does not appear to be applicable.