As far as I know, the nutrients of pasteurized milk are the best, but the shelf life of this kind of milk is relatively short, only a few days, so it is still relatively rare in China. There are more overseas. In China, high-temperature sterilization is mostly used. This method has a longer shelf life, but it kills harmful bacteria as well as beneficial bacteria in the intestines. Here is what I am looking for…. Fresh milk packaged in paper bags (Tetra Pak) has a good taste, and the shelf life is: Tetra Pak Pillow 45 to 50 days; Tetra Pak Brick 6 months. Fresh milk packaged in plastic bags (Bailey) has a poor taste and often smells like plastic bags. , and it is easier to taste bitter (I have encountered milk that tastes bitter when it goes bad), and has a shelf life of 30 days. . As far as I know, the nutrients of pasteurized milk are the best, but the shelf life of this kind of milk is relatively short, only a few days, so it is still relatively rare in China, and more abroad. In China, high-temperature sterilization is mostly used. This method has a longer shelf life, but it kills harmful bacteria as well as beneficial bacteria in the intestines. Here is what I am looking for…. These are two different packaging forms. The paper packaging is called Tetra Pak. The difference between these two packaging forms will have different requirements for the processing technology. What you call thicker means that the milk packaged in Tetra Pak is fresher. Processing and packaging times are short. The price difference is due to different packaging costs. Tetra Pak's packaging has applied for a patent, and it can only be used in China... You can compare the ingredients yourself: If the varieties are the same, there is no difference in quality. The difference is in the packaging material. Just like Coke: canned (the material is expensive, so the price is high) Coke bottle (can be reused, so it's cheap) The same goes for milk. Tetra Pak pillowcases have fewer material layers, so the shelf life is relatively short. The price is cheap. Tetra Pak…. The nutritional content is the same. It's just that their processing methods are different. Paper bags generally use the instant sterilization method, and plastic bags use the pasteurization method. Therefore, the shelf life is different, paper bags are generally 45 days, and plastic bags are shorter, 30 days. . plastic. ． . The concentration in the carton is higher and the nutrition is better preserved. Of course, it is also more expensive and easy to carry. The simple packaging is affordable and economical for daily use at home. They are all the same, but the packaging is different, and the packaging cost of paper bags is high. Sound insulation materials are generally thick and heavy materials. Heavier materials of the same volume are denser and difficult for sound to penetrate, so I choose foam plastic, which is thicker/haha! Spray k-18 is a kind of sound-absorbing fiber sound-absorbing material.