Changes of flavonoid content in some vegetables and fruits during cooking

本研究的目的是研究蔬菜和水果中黄酮类化合物的含量及其在加热过程中的变化，为黄酮类化合物的摄入提供实用数据。选择几种蔬菜和水果，提取和水解得到样品溶液。下面是高效液相色谱法分析黄酮类化合物的新结果；不同肤色的辣椒中总黄酮含量不同。对红辣椒和普通青椒的总黄酮含量进行比较，发现两者之间存在显著差异。柑橘类水果中含有大量的柚皮素和橙皮素，这两种成分占总黄酮的90%以上。槲皮素、山奈酚、木犀草素和芹菜素主要存在于蔬菜中。根据蔬菜种类的不同，总黄酮的含量有相当大的差异。一般来说，在煮沸或微波炉加热后，总黄酮容易减少。

The purpose of this study is to investigate the quantities of flavonoids contained in vegetables and fruits together with their changes due to heating in order to provide practical data for the intake of flavonoids. Several kinds of vegetables and fruits were selected, extracted and hydrolyzed to obtain sample solutions. Here are the new results of the analyses of flavonoids by high-performance liquid chromatography ;1.The total flavonoids in paprika showed differences depending on the color of skin. Comparison of the total flavonoids between paprika and conventional green peppers reveals significant differences between the two.2.Naringenin and hesperetin are abundantly contained in citrus fruits, and these two ingredients account for 90 percent or more of the total flavonoids.3.Chiefly quercetin, kaempferol, luteolin and apigenin are found in vegetables. These are considerable differences in the total flavonoids depending on the type of vegetable. As a general rule, total flavonoids are prone to decrease after boiled or heated in a microwave oven.