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Processing and Bioavailability (WG2) page 49
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Carotenoids are passively absorbed along with lipids. The efficiency of absorption of the
carotenoids is, therefore, dependent on releasing the lipophilic molecules and crystals of
carotenoids from the food microstructure and dissolution into dietary lipids during processing
or domestic preparation, and during the digestive processes. It is now recognised that release
and dissolution are the most important factors governing carotenoid bioavailability; so it is
not surprising to find greater lycopene bioavailability from heat-treated tomato products that
have been comminuted or co-processed with oils (Grtner et al., 1997, Porrini et al., 1998,
Stahl and Sies, 1992a).
Why is the study of carotenoid bioavailability so important ?
• Knowledge of the total amount of a carotenoid in a food does not predict the amount of
carotenoid available to the body; this will depend intimately on food microstructure and diet
composition.
• Epidemiologic associations between dietary carotenoids and disease incidence cannot
be seen as causal; demonstration that the carotenoid is absorbed in sufficient and dose
responsive amounts is required.