Sterilization is an important part of beverage processing. Beverage sterilization is different from medical and biological sterilization. Beverage sterilization has two meanings: one is to kill the pathogenic bacteria and spoilage bacteria in the beverage, destroy the enzymes in the food and make the beverage in a specific environment, such as a closed bottle, can or other packaging container , There is a certain shelf life; Second, it is required to protect the nutrients and flavor in the beverage as much as possible during the sterilization process. Therefore, the sterilized beverage is commercially sterile.
There are two types of beverage sterilization methods: physical sterilization and chemical sterilization. The chemical sterilization method uses bactericides such as hydrogen peroxide, ethylene oxide, and sodium hypochlorite. Due to the effects of chemical residues in chemical sterilization, contemporary food sterilization methods tend to be physical sterilization methods. The physical sterilization method is divided into thermal sterilization method and cold sterilization method. Thermal sterilization method is divided into thermal sterilization method, dry heat sterilization method, microwave sterilization method and far infrared heating sterilization method. Cold sterilization method is divided into ultraviolet radiation sterilization method, ionizing radiation sterilization method and freezing sterilization method. Among the damp heat sterilization methods, there are the pasteurization method, high temperature short-term sterilization method and ultra high temperature instant sterilization method. The so-called pasteurization (pasteurization) is a low-temperature long-term sterilization method, the sterilization temperature is lower than 100 ℃, the holding time is 30min. High temperature short-term sterilization method (HTST), the sterilization temperature is generally below 100 ℃, such as milk HTST sterilization temperature is 85 ℃, maintained for more than 15s. Ultra high temperature instant sterilization (UHT), the sterilization temperature is above 120 ℃, only for a few seconds. HTST and UHT sterilization methods are not only highly efficient, but also the structure and appearance of food and the preservation of nutrition and flavor are better than other sterilization methods.