Files
Abstract
The â-carotene and total carotenoids and the effect of cooking on the retention ofthese carotenoids were studied using amaranth, chayote leave, kang-kong, lettuce,moringa and sweet potato leaves .The various carotenoids were analyzed byhigh-performance liquid chromatography with photodiode array detection. The majorcarotenoids identified after HPLC analysis in samples were violaxanthin, neoxanthin,lutein,á-carotene, â-carotene. These carotenoids are all affected by cooking, lutein isthe most stable but violaxanthin is the least stable. The cooking practices resulted in asignificant decrease in the concentration of total carotenoid and â-carotene for all thevegetables. Cooking resulted in a 100% loss of â-carotene from Kang-kong andchayote leave, respectively. Results of this study indicated that raw and cookedvegetables all have trans and cis forms, but in different amounts. In raw vegetables,9-cis-â-carotene is not found in this study. Carotenoids can lose provitamin A activitybecause of formation of cis-isomer during heating. After cooking the amount of totalcarotenoid loss 68% in Kang kong and only 20% in moringa. Moringa also has largeamount of total carotenoid and high retention. Therefore, moringa is the most suitablefor cooking among the selected vegetables.