Overview of Sterile Packaging As a result of the continuous contamination of various microorganisms during the production, packaging, transportation, and storage of articles, the articles carry a large variety of microorganisms. Can use the previously mentioned chemical agents, gas-conditioning, high temperature, low temperature and other sterilization technology for sterilization. However, sterilization alone is not enough, because many items cannot be kept in the bactericidal environment at all times. Once they leave the sterilizing environment, they will infect microorganisms, which will also cause deterioration of the items. Therefore, after sterilization, we must carry out the necessary post-treatment of the items in an aseptic environment. That is, the sterilized items are isolated from the external environment by packaging methods such as sealing, vacuuming, inflating, or blistering. These processes are a series of continuous processes.
First, the definition of aseptic packaging technology The so-called aseptic packaging technology is in the case of packaging, packaging containers or materials, packaging aids in the case of aseptic, filling and sealing in a sterile environment of a packaging technology. The main research object of aseptic packaging technology is food and beverage packaging, followed by packaging of heat-sensitive products (such as medicine). The aseptically packaged foods can be stored at room temperature without deterioration, with little loss of color, fragrance, and nutrients, for example, vitamins can hold 95%, and the quality of the product can be maintained regardless of the size of the package.
Second, food aseptic packaging classification (1) according to the food inside and outside the container is divided into: sterilization and final sterile processing. Final sterilization means that after the packaged articles are filled into the containers, they are tightly sealed and then sterilized. Sterilization of canned foods, beer, etc. falls into this category. Aseptic processing usually involves four different operations, ie, the packaging equipment is pre-sterilized, the items are sterilized before filling, the packaging materials (or containers) are sterilized, and the packaging environment is sterilized. That is, the sterilized articles are filled into aseptic packaging materials (containers) in a sterile environment (including equipment) and tightly sealed. This food is called aseptically packaged food.
(2) Divided into three categories according to sterilization methods: heat sterilization, radiation sterilization, and sterilization of chemical drugs. Heating and sterilizing devices mainly include sterilizing channels and sterilizing kettles. Dry heat sterilization channels are divided into radiation channels and laminar flow channels. For example, the British JohnBurge Cozzoli series of sterilizing passages are radiant dry heat passages. This unit is divided into drying and heating sections. It is sterilized with high-intensity and uniform infrared radiation, and then cooled through three cooling zones to 38°C. Stunck's sterilization channel is a dry hot laminar flow. It uses a sterilized and filtered hot air at 350°C to fully treat the container to be sterilized and the packaged articles, and to maintain the circulation of hot air inside the channel.
The sterilizing autoclave uses supersaturated steam to sterilize the microorganisms in the temperature range of 115 to 138°C, because most of the microbes are less resistant to heat and heat than the dry and heat resistant ones, so they can achieve better bactericidal effects. Radiation sterilization is mainly used ultraviolet radiation, far infrared radiation, radiation (γ-rays, β-rays), microwaves and other electromagnetic radiation sterilization, which is a new type of physical sterilization. Chemical agents are used to sterilize foodstuffs and are first used in beverage water. However, chemical agents are directly related to the safety of foods. Therefore, the relevant departments of various countries strictly control the sterilizing of foodstuffs. Most of the regulations stipulate that all bactericides cannot be directly added to foods. Only allowed for water and environmental sterilization.
Chlorides, hypochlorites, iodine preparations, quaternary ammonium salts, amphoteric surfactants, ampullaviruses, and ethanol are all used as bactericidal agents. See Table 7-1.
Table 7-1 Biocides used in food factories