Changes in individual carotenoids on processing and storage of mango (Mangifera indica) slices and purée

Susceptibility of different carotenoids to degradation during thermal processing and storage of two mango cultivars was investigated. The carotenoid composition was practically maintained on processing mango (cultivar Tommy Atkins) slices. The only significant change was the increase in luteoxanthin, compatible with the conversion of 5,6- to 5,8-epoxide. More evident transformations occurred on processing mango (cultivar Golden) purée. The major pigment β-carotene decreased 13%, resulting in a corresponding reduction of the vitamin A value. Auroxanthin, not found in the fresh fruit, appeared while violaxanthin and luteoxanthin decreased. During storage of mango slices in lacquered (epoxy) or plain tin-plate cans, no appreciable loss of β-carotene was observed during 10 months. Between the tenth and fourteenth month, about 50% reduction of β-carotene occurred. The degradation continued, resulting in a total loss of 84% after 24 months. A tendency of violaxanthin to decrease, and auroxanthin to increase, during storage was also noted. β-carotene showed a greater susceptibility to degrade in bottled mango purée (18% loss after 10 months) than in the canned product. As in the case of mango slices, however, both bottled and canned purée suffered 50% loss of β-carotene after the tenth month, and a total loss of 83% after 24 months. Violaxanthin and luteoxanthin tended to decrease while auroxanthin maintained a comparatively high level throughout storage. The vitamin A values reflected the degradation trend of β-carotene, a pattern that appears to agree with a free radical mechanism.