Zeaxanthin presented a different behaviour, compared with the
remaining carotenoids, by presenting an increase with thermal
treatment. After pasteurization of fresh peach zeaxanthin increased336% and after pasteurization of frozen samples increased 127%
(Fig. 2B). The b-carotene was the carotenoid more stable, presenting
only a significant increase of 30% after pasteurization of fresh
samples (Fig. 2B). Little effect of freezing was reported by Scott and
Eldridge (2005) for corn lutein content and also in b-cryptoxanthin
and b-carotene from another cultivar. Zeaxanthin stability was reported
by Maiani et al. (2009) on potato and a similar trend was
also observed in sweet corn after a heat treatment
. Gradual dissociation of zeaxanthin from the
native protein complex stimulated by previous heat treatment may
explain the observed increase. Thermal treatment may be beneficial for carotenoids
content through the disruption of food matrices facilitating the liberation (bound) and solubilisation of
carotenoids (free and ester forms) resulting in an increased carotenoid
bioavailability