To prevent apple jam from spoilage, we can try these two methods: (1) storage: low temperature can inhibit the reproduction of microorganisms, reduce the speed of chemical reaction and the activity of enzymes in food. Generally, meat can be stored for 7 ~ 10 days at 0℃ and for half a year at-10℃. The freezing temperature of fish should be -5℃ ~-30℃. Fruits and vegetables should be stored at 0℃ ~ 5℃. (2) High-temperature sterilization and bacteria prevention: After high-temperature treatment, most microorganisms can be killed and enzymes in food can be destroyed. However, the effect on microorganisms depends on temperature and heating time. Most microorganisms can be killed in 10 ~ 15 minutes at 60℃, but bacterial spores and molds need higher temperature or longer time because of their strong tolerance.