As the Spring Festival approaches, many people begin to prepare new year's products, of which pig, cow and mutton are almost a must for every family. Recently, a video has attracted the attention of many netizens. In the video, the fresh meat just cut from the slaughtered cattle and sheep jumped up by itself. So many people expressed concern: what's going on? Are there parasites in the meat? Is the beating beef and mutton still edible? Energy and substance in muscle are not exhausted In animals that have just been slaughtered, the pivot nerve has died, but the nerve endings around the muscle have not completely died, and the energy substance adenosine triphosphate (ATP) in the muscle has not been exhausted. Therefore, when slightly stimulated by the outside world, their muscles may also beat. This is also known as "superbiosis reaction", not because there are parasites in the meat. When adenosine triphosphate in the muscles of animals to be slaughtered is exhausted, their muscle fibers will lose "vitality" and no longer beat. Therefore, the meat that can "jump" is usually fresh. For good meat quality, storage methods are very important Some people like to eat meat from slaughtered pigs, cattle and sheep. It is best to slaughter it in the early morning of the day and cook it at noon or at night. But this method of eating meat is not scientific. The meat cut from the animals that have just been slaughtered is also called hot fresh meat. Its meat is soft, but if it has not been cooled down, after a few hours, the meat will enter a period of rigidity, and the muscles will contract strongly, resulting in stiffening and poor taste. Some people will ask, if you quickly freeze the hot and fresh meat, will the meat not harden? The answer is regrettable. After freezing the hot fresh meat quickly, the low temperature will make the muscle contract more strongly, making the meat harder. This kind of meat is called frozen meat. So, what can be done to soften frozen meat again? The method is to quickly store the frozen meat in a low temperature environment of 0 to 4 degrees Celsius for 1 to 2 days, the meat will slowly return to soft, and always keep it in an environment of 0 to 4 degrees Celsius in the subsequent processing, circulation and sales process. This is what we usually call cold fresh meat. These are the reasons for the preservation of cold fresh meat What changes will take place in the process of turning hot meat into cold meat? First of all, the naturally occurring protease in the meat will moderately decompose the protein and produce peptides and amino acids, so as to make the muscle softer and easier to cut. The cut surface has a special aromatic smell. It is cooked and easy to rot, and the taste is delicate and juicy. Secondly, the muscle cells in the meat breathe without oxygen, so that the glycogen stored in the meat is decomposed into lactic acid, and the lactic acid will be further decomposed into carbon dioxide, water and alcohol, and then volatilized, making the meat delicious. Therefore, cold fresh meat is also known as sour meat. Finally, adenosine triphosphate in meat is broken down into phosphoric acid and hypoxanthine, producing substances that make meat more fragrant. Therefore, not all freshly killed meat tastes good. If fresh meat is not put into the pot immediately, it is best to go through a few days of low-temperature cold chain treatment at 0 to 4 ℃, which will not only make the meat delicate and soft, but also inhibit the growth of microorganisms, prevent meat corruption, and greatly improve the quality and safety of meat. Related links Remember these points, good meat buyers The market is full of meat. How can we choose fresh and high-quality cold meat? We can judge the quality of meat according to the color, appearance, smell and other factors of meat. First, take a look. The color of cold fresh meat is light bright red, and its surface is shiny. The color of non cold fresh meat is dark and blood red, and its surface lacks luster. Second, smell it. Cold fresh meat has no particularly strong fishy smell and has a fragrance. Again, press. Cold fresh meat is elastic and can recover in time after being pressed; The elasticity of non cold fresh meat is poor and cannot recover in time after being pressed. Finally, I would like to remind you that it is best to buy and cook cold and fresh meat on the same day. If you can't finish eating, you can put it in the refrigerator, refrigerate at 0 to 4 ℃ for 2 to 3 days, and eat it as soon as possible. (outlook new era)