Application of sterilization in food

In food processing and production, through food sterilization technology, the growth of microorganisms can be inhibited or killed, thus improving food quality, prolonging food shelf life and ensuring food safety.

First, the traditional thermal sterilization technology

The essence of traditional thermal sterilization technology is to provide heat energy outside the food by burning fuel or resistance heating, and transfer the heat energy to the inside of the food by conduction and convection, so as to achieve the purpose of sterilization and enzyme inactivation. Pasteurization and disinfection are often used in food processing.

1, pasteurization: refers to the heat treatment intensity that can kill almost all pathogenic bacteria in food. The degree of heat treatment depends on the heat resistance of the target bacteria in the target product.

2. Sterilization: Sterilization refers to the heat treatment intensity that can kill almost all microorganisms including spores in food. The intensity of sterilization is higher than pasteurization.

Second, the new thermal sterilization technology

The ideal thermal sterilization effect should be to quickly and effectively kill harmful microorganisms in food raw materials under the condition that the influence of heat on food quality is limited to the minimum, so as to meet the requirements of product indicators. Ultra-high temperature sterilization, microwave sterilization and ohmic sterilization are new methods to achieve this ideal effect.

1. Ultra-high temperature sterilization: refers to the sterilization process in which the heating temperature is 135~ 150℃ and the heating time is 2~8s, and the products after heating meet the commercial aseptic requirements. This sterilization condition is 20~40℃ higher than 100~ 135℃ used for conventional sterilization of low-acid foods, so it is called ultra-high temperature sterilization.

2. Microwave sterilization: Microwave refers to the ultra-high frequency electromagnetic wave with the frequency of 300MHz~300GHz, that is, the wavelength is1m ~1mm. Microwave sterilization is the result of both thermal and non-thermal effects.