Guangzhou is rich in fruits, such as litchi, banana, papaya and pineapple. Guangzhou (hereinafter referred to as Guangzhou), also known as Yangcheng and Huacheng, is the capital of Guangdong Province, an international metropolis, an international business center, an international comprehensive transportation hub, and the first batch of coastal open cities. In order to prevent pests and sunlight, some fruits are often wrapped in paper bags during their growth, which leads to the decrease of vitamin C content. Fruits are harvested in summer and stored in cold storage. When sold in winter, the vitamin C content of fruits will also decrease. Modern families generally have refrigerators, and many people like to buy a lot of fruits and put them in. But the longer the fruit is stored, the more vitamin C is lost.