Represented in flexible packaging is a retort pouch made of three layers of material - an aluminum foil pouch, the outer layer of which is a polyester film, the intermediate material is an aluminum foil, and the inner layer of material is polypropylene. The commonly used equipment is a vacuum packaging machine, and the meat canned food with soft packaging as a packaging container is now widely used due to its convenience of eating and storage at room temperature.
Vacuum packaging: The purpose of vacuum packaging is to extract the air inside the aluminum foil bag, so that the food in the bag is in a vacuum state, preventing the aluminum foil bag from being deformed or damaged during high temperature sterilization; preventing the color, fragrance, taste change and aerobicity of the food inside the bag. Breeding of sexual bacteria to avoid spoilage of food. The equipment used for vacuum packaging is a vacuum packaging machine, which mainly consists of a vacuum pump and a working chamber. Generally divided into three types: automatic, double room, single room. The working parameters of vacuum packaging are heat sealing temperature, pumping time, heat sealing time, and different working parameters are selected according to different materials, size and thickness of flexible packaging. It is best to achieve the required vacuuming effect. After the vacuum packaging is completed, the aluminum foil bag should be tight and airless, the sealing is tight, and the bag surface is not damaged. Otherwise, the bag must be repackaged to avoid the defective product.
High temperature sterilization: The purpose of high temperature sterilization is to kill bacteria contaminated in food and destroy the enzyme in food, so that the shelf life of food is more than one year at normal temperature. High temperature sterilization is carried out by using high temperature steam. For the sterilization pot, it mainly consists of a pot body and a pot door. Generally divided into three types: fully automatic, horizontal, and vertical. The supporting equipment includes steam boilers, air compressors, pumps and so on.
The working parameters of high temperature sterilization are sterilization temperature, heating time, constant temperature sterilization time, cooling time and back pressure, and different working parameters are selected according to the different net content of soft packaged meat can. When the temperature in the pot drops to the specified shipping temperature, the cooling water can be stopped, and the drain valve and exhaust valve can be opened, and the water in the pot can be drained before the pot door can be opened for shipment. After the sterilization is completed, it is necessary to carry out inspections. The canned soft-packed meat can be placed in the reservoir, and the sinking into the bottom of the water is a good product; the floating product is a non-conforming product (caused by a broken bag), which accounts for about two thousandths. Prove that this is an effective method.
In short, after packaging and high-temperature sterilization of the vacuum packaging machine, the canned meat can be used for one year or even longer under normal temperature conditions. It satisfies the demand for specific functions of packaging technology for meat, potato chips, milk powder and other easily oxidized solid and powder foods.