Acid-discharged meat, also known as chilled meat, is a post-ripening technology advocated by modern meat hygiene and nutrition. Acid-discharged meat is a kind of meat that is naturally cooled to normal temperature after slaughter of live animals and then sent to the cooling room. Under certain temperature, humidity and wind speed, lactic acid in meat is decomposed into carbon dioxide, water and alcohol, and then volatilized. At the same time, adenosine triphosphate in cells is decomposed into umami glycoside IMP (the main component of monosodium glutamate) under the action of enzymes. After acid removal, the taste of the meat is greatly improved, the taste is fresh and tender, the pH value of the meat changes, and the metabolism is improved. Fresh meat has different edible values in different periods after a series of chemical and biochemical changes such as stiffness, maturity and corruption.