In recent years there has been room temperature milk in China, also called ultra-high temperature sterilized milk. This kind of milk is used 130 ~ 150 ℃ ultra-high temperature sterilization after filling. This sterilization method not only destroys all the biologically active substances and most of the vitamins in fresh milk, but also makes the easily absorbed calcium ions combine with the casein of milk to form complexes that are not easily absorbed. Room temperature milk was once popular in some countries, but now developed countries have banned the use of ultra-high-temperature process milk processing.
From a nutritional point of view, the nutritional value of various types of milk is ranked in the following order: fresh milk is gold, yogurt is silver, powdered milk is copper, room temperature milk is iron. If you evaluate the nutritional value of milk according to packaging, the house type carton fresh milk 100 points, glass bottles and plastic bags of fresh milk 90 points, with raw milk fermented yogurt 80 points, fortified milk powder 60 points, with milk powder fermented yogurt 50 points, room temperature milk 40 points. This is because making house-type carton fresh milk requires the highest quality of raw milk and the best filling aseptic conditions and shelf life. Fresh milk in glass bottles and plastic bags scored lower due to factors such as poor protection from light and air permeability. In addition, milk has a very strong adsorption of odor characteristics, such as milk and green onions together, the next day the milk will have a green onion flavor. If the milk is packed in a plastic bag, it will inevitably have a plastic odor. It can be seen that no matter which way you look at it, the nutritional value of room temperature milk is ranked last.
Yogurt scores higher than room temperature milk because it is antibiotic-free and contains beneficial lactic acid bacteria. Powdered milk scores higher than room temperature milk because it has a variety of vitamins and minerals such as calcium, iron and zinc added. The main reason why foreign milk powder is expensive is the brand name it sells. Compared with fresh milk, the highest scoring of all kinds of milk powder can only be 60 points.
The reason why room temperature milk is popular is due to the advertising effect. Its four major selling points are:
1. Convenience. Sold in full cases and stored at room temperature can be kept for dozens to hundreds of days.
2. Prairie concept. People can often see in the TV commercials "our cattle eat grass, drink mineral water" and other advertising slogan. In fact, the nutritional value of milk produced by dairy cows that eat grass as their main food is not as good as the milk produced by scientifically raised dairy cows.
3. Production date near. The state expressly provides: room temperature milk must be 7 days after the bacteriological inspection before the market. But the vast majority of room temperature milk is processed immediately after the factory, so room temperature milk packaging labeled production date is mostly within a week.
4. flavorful. As a result of the addition of chemically synthesized milk flavoring or cream and other high-fat substances, so room temperature milk is generally very flavorful and delicious.