44D-7 |
Effect of different heat treatments on the retention of carotenoids in nopal (Opuntia ficus-indica) |
M. E. JARAMILLO-FLORES1, L. González-Cruz, L. Dorantes-Alvarez, G. Gutiérrez-López, and H. Hernández-Sánchez. (1) Dept. de Graduados e Investigación en Alimentos, Escuela Nacional de Ciencias Biológicas - IPN, Carpio y Plan de Ayala, Mexico, 11340, Mexico The use of the nopal as a vegetable in the arid zones of Mexico is widely spread and is a very important part of the diet of many Mexicans. The more common species of nopal is Opuntia ficus-indica which can be considered a good source of carotenoids, however it is necessary to know which carotenoids are present in order to evaluate their real importance. The objective of this research is to identify and quantitate the main carotenoids in the nopal and also to evaluate their retention after different heat treatments. The identification and quantitation of the carotenoids was done according to the techniques of Rodriguez-Amaya. The standards were obtained by the open column methodology (MgO:Celite 1:2) and the quantitation was done by HPLC using a C18 Prodigy 5 m ODS column. Antioxidant capacity was also evaluated. The analysis showed that tha main carotenoids present in nopal are b-carotene, lutein and a-cryptoxhantin at concentrations of 82.4, 107.36 and 41.99 mg/g (dry basis) respectively. Generally, it was observed that heat treatments increase the extractability of the carotenoids. Maximal levels of a-cryptoxhantin and b-carotene were obtained in nopal treated at 115°C for 20 min. In the case of lutein, the best treatment was 115°C for 10 min. The antioxidant activity increased after all the treatments. The results indicate that cooked nopal can be a good source of antioxidant compounds.
Session 44D, International
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