Milk contains in its composition and delivers to our body all vitamins of group B, A, D and calcium, it is not without reason that it is recommended to include it in our daily diet. The use of this product reduces the risk of many diseases, including osteoporosis and diabetes. Before going on sale, milk is subjected to heat treatment, which significantly increases its shelf life and reduces the quality of the product.
Milk sterilization methods
- Sterilization is a process in which milk is heated to 120-130 degrees. With this method of processing, all the beneficial properties of milk are lost, its original taste changes.
- Ultra-pasteurization is a more gentle sterilization with short-term heating of milk to 140 degrees, followed by instant cooling and instant packaging. The shelf life of the product when processed by these methods is increased to six months.
- Pasteurization is a method in which gentle heating occurs, and the product is not brought to a boil. Vitamins, microelements and taste of milk are preserved, and harmful microflora is destroyed. The shelf life of such a product is only 10 days.
- Baked milk - pre-pasteurized milk, languishing for three to four hours at a temperature of 95 degrees in a closed container. Unlike pasteurized, it contains up to 6% fat, calcium, vitamin A and iron, but the amount of vitamins C and B decreases. Shelf life is 10 days.
Additional methods to increase the shelf life of milk
In addition to heat treatment of milk to increase the shelf life in production, there are several additional methods.
Homogenization - equalization of the consistency of milk. Fat molecules are broken into small parts and cream is no longer collected in the top of the bag, this prevents the milk from going rancid and increases the shelf life. The air tends to sour milk, so the milk is poured into sterile bags in a matter of seconds after pasteurization.
Packaging is essential for extending shelf life. So, the most popular polyethylene bags are breathable, so the product is stored in them for only two days. Very good packaging - tetrapak, but expensive to manufacture, so milk in it is much more expensive than in polyethylene one. In order to pour milk into a tetrapack, a sterile workshop is needed, because the packages are disassembled on the line and assembled on the conveyor. The shelf life in such packaging increases from three to six months.
Another type of packaging is Swedish Ecolean jugs. These packages arrive on the conveyor in a sealed form, opened by an automatic machine, filled with milk and immediately sealed. Air contact is minimized. The shelf life of fresh milk in such a package is up to ten days.
