Generally speaking, the temperature at the door of the refrigerator is the highest, and it is the lowest near the back wall; The upper layer of the refrigerator is warmer and the lower layer is colder. Therefore, the refrigerator freezer can be divided into several areas according to the temperature order: refrigerator door frame, upper door, upper back wall, lower door, lower back wall and fresh-keeping box. At present, the multi-temperature fresh-keeping refrigerator is developed to solve the problem of food partition fresh-keeping The effect of an ice greenhouse is different from that of a cold room. Through the nutrition test of food stored in refrigerator in four-temperature area. The data showed that the chlorophyll retention rate of green leafy vegetables in ice greenhouse was significantly higher than that in cold storage, which kept the chlorophyll content of such fruits and vegetables well and avoided the yellowing of green leafy vegetables. Fruit is an important source of vitamin C. After 0/5 days of storage in ice greenhouse, the retention rate of vitamin C was 5 ~ 2 1% higher than that in cold room. However, the fresh-keeping period of meat and milk in ice greenhouse is longer than that in cold room 1 ~ 3 days. Suitable for the lower floor behind. Uncooked food that needs to be preserved at low temperature, such as tofu, Aral Sea, etc. , as well as tightly packed foods that are not afraid of cross contamination, and foods that are waiting to be slowly thawed are suitable for storage in the coldest places, such as the back lower wall.