In August 2000, some nutritional qualities of pitaya were determined. The test material pitaya is a red-skinned and white-fleshed variety, which was purchased from Chaozhou fruit and vegetable market and cultivated locally. Determination method: The content of soluble solids (TSS) was determined by Abbe refractometer. Vitamin C(VitC) was titrated with 2,6-dichlorophenol indophenol [1]; The content of protein was determined by Coomassie brilliant blue staining, and bovine serum protein was the blank control [2]. The moisture content is determined by a rapid moisture analyzer. The determination was carried out at room temperature in the laboratory, repeated three times and averaged. See table 1 for the determination results.

The results are consistent with those reported by Chen Zhendong and others. In addition, according to Chen Zhendong and others, every 100g of pitaya fruit also contains 0.2 1~0.6 1g of fat, 0.7~0.9 mg of fiber, 0.005 ~ 0.0/kloc-0.2 mg of carotene and 6.3 ~ 8.8mg of calcium.

2. The health function of pitaya

Because pitaya has the above components, it determines the dietotherapy and medicinal functions of pitaya. Literature [4] records that the flowers of pitaya have medicinal value and are sweet, light, cool and fragrant. Clearing heat, moistening lung and relieving cough. It can be used for treating cough, hemoptysis and cervical lymph node tuberculosis. Stem cures parotitis, hernia and carbuncle. Pitaya is a fruit cultivation variety with a measuring ruler, so its flowers and stems should have the same curative effect as the medical measuring ruler. As we know, dietary fiber is called the seventh nutrient element in human body, which has the functions of lowering plasma cholesterol, improving blood sugar production reaction, preventing constipation and colon cancer, controlling weight, reducing estrogen level, detoxification and so on [5]. As a fruit with low calorie and high fiber, the dietotherapy effect of pitaya is self-evident. Regular consumption of pitaya can lower blood pressure, reduce blood fat, moisten lung and detoxify, beautify and improve eyesight, and has an auxiliary treatment effect on constipation and diabetes. The pitaya with low calorie and high fiber is also the most ideal food for people who want to lose weight and beautify, which can prevent the spread of "urban rich disease".