Effects of various heating methods on glucosinolate, carotenoid and tocopherol concentrations in broccoli.

摘要

The influence of boiling, steaming and microwaving on carotenoid, tocopherol and glucosinolate concn. in broccoli was determined. 5 glucosinolate peaks were detected in broccoli representing glucoraphanin, 4-hydroxyglucobrassin, glucobrassicin, 4-methoxyglucobrassicin and neoglucobrassicin. Various heating methods affected the concn. of nutrients and health-promoting compounds in cruciferous vegetables. The concn. of 5 glucosinolates in broccoli significantly decreased after different heating methods, and the rate of decrease was higher with increased cooking time. Cooking broccoli significantly increased the apparent concn. of lutein, beta-carotene and alpha- and gamma-tocopherols. Results clearly showed that health-promoting compounds in broccoli are significantly affected by different heating methods, and that all heating treatments reduced glucosinolate concn. However, carotenoid and tocopherol concn. were increased by various heating methods, and a longer heating time increased their extractability.