As a traditional Chinese delicacy, zongzi is widely cherished both during festive occasions and in everyday life. However, the shelf life of zongzi varies significantly depending on its preparation method and packaging style. In particular, how does the shelf life of zongzi treated with sterilization equipment differ? This article provides a detailed analysis of this issue.

　　I. Shelf Life of Traditional Zongzi

　　Regular zongzi: Fresh, standard‑style zongzi are typically prepared by steaming or boiling and should be consumed as soon as possible after purchase. Even when stored in a refrigerator at 4°C, they generally remain safe to eat for only 3 to 5 days. This is because high‑temperature cooking can kill some microorganisms, but it cannot completely prevent the growth and reproduction of all bacteria.

　　Homemade zongzi: Zongzi made at home typically undergoes no rigorous sterilization, so its shelf life is shorter. Even when refrigerated, such zongzi should be consumed within a few days to prevent spoilage.

　　II. The Impact of Sterilization Equipment on the Shelf Life of Zongzi

　　Vacuum packaging and high‑temperature sterilization: Commonly available vacuum‑packed zongzi inhibit microbial growth by removing oxygen from the package, and when combined with high‑temperature sterilization, they can significantly extend shelf life. Under normal conditions, such zongzi can be stored at room temperature for 3 to 6 months. High‑temperature sterilization uses heat at 120°C to eliminate bacteria in the food, reducing bacterial counts to meet national food safety standards and thereby effectively prolonging the product’s shelf life.

　　Microwave sterilization technology: Microwave sterilization is an efficient, energy‑saving, and reliable new technique that rapidly inactivates microorganisms in food. This method is not only easy to operate but also avoids contaminating the product, preserving the original flavor and nutritional content of zongzi.

　　III. Comparison of Different Sterilization Equipment

　　Water‑bath sterilization kettle: Uses hot water for sterilization and is suitable for a wide range of food products. Its advantage is uniform temperature distribution, but it consumes relatively large amounts of energy.

　　Spray‑type sterilization kettle: Sterilization is achieved by spraying hot water or steam, making it suitable for large‑scale production. It is characterized by highly effective sterilization, though at a relatively high cost.

　　Ultraviolet and ozone sterilizers: These devices use ultraviolet light and ozone to disinfect, eliminating the need for high temperatures and making them suitable for temperature-sensitive foods. Their drawback is that they can only achieve surface-level sterilization.

　　Pasteurization and UHT sterilization: These methods employ relatively low temperatures—typically not exceeding 100°C—for extended processing times, making them suitable for liquid foods as well as certain solid foods.

　　IV. Development of Food Preservation Technologies

　　With the widespread adoption of technologies such as the Internet of Things, food preservation is advancing toward intelligent monitoring and early warning systems, ensuring food safety and quality while boosting production efficiency. For instance, smart sensors can continuously track storage conditions, automatically regulate temperature and humidity, and extend shelf life. Meanwhile, emerging techniques like high-pressure processing and irradiation are being increasingly implemented, offering additional options for preserving food.

　　After being treated with sterilization equipment, the shelf life of zongzi is significantly extended. Selecting the appropriate sterilization method and equipment not only ensures the product’s quality and taste but also meets consumers’ demands for food safety and extended shelf life. As food‑preservation technologies continue to advance, we can look forward to a future in which food supplies are safer, longer‑lasting, and more delicious.