In the process of meat processing, non-pigmented chemicals are appropriately added to give them a good color. These substances are called color formers or color-protecting agents and color formers. While using a color former, it is also often added with some reducing substances which promote color development, and these substances are called chromophoric auxiliary agents. Commonly used hair coloring agents are potassium nitrate, potassium nitrite, sodium nitrate, sodium nitrite; commonly used hair coloring agents are L-ascorbic acid and its sodium salt, isoascorbic acid and its sodium salt, nicotinamide and the like. First, the color development mechanism of the coloring agent: The red color of the raw meat is a sensory trait exhibited by myoglobin (Mb) and hemoglobin (Hb). The content and proportion are different due to differences in meat parts and livestock breeds. In general, myoglobin accounts for about 70% to 90%, and hemoglobin accounts for about 10% to 30%. Thus, myoglobin is the main component that makes meat color. Myoglobin in fresh meat is reduced, dark purple, very unstable, and easily oxidized and discolored. The bound water on the divalent iron ion in the reduced myoglobin molecule is replaced by oxygen in the molecular state to form oxygenated myoglobin (MbO2), which is bright red. At this time, the iron is still divalent, so this combination is not oxidized but is called oxygenation. When oxygenated myoglobin further oxidizes ferrous iron to ferric iron in the presence of oxygen or an oxidizing agent, brown high-myoglobin is produced. In order to give the meat a bright red color, nitrate and nitrite are often added during processing. They are often the ingredients of salt mixed when marinated. Nitrate is reduced to nitrite by the action of nitrous acid bacteria, and nitrite can form nitrous acid under acidic conditions. Generally, the mature meat after slaughter contains lactic acid, and the pH is about 5.6-5.8, so nitrous acid can be formed without external acid. The reaction is: NaNO2+CH3CHOHCOOH→HNO2+ CH3CHOHCOONa (1) Nitrous acid is very unstable and can be decomposed to produce nitroso (NO) even at normal temperature: HNO2→H+ +NO-3+NO+H2O (2) The nitroso formed quickly reacts with myoglobin to produce bright, bright red nitrosyl myoglobin (MbNO2): Mb+NO→MbNO (3) Nitrosyl myoglobin releases thiol (-SH) upon exposure to heat, resulting in a more stable nitrosochrome with bright red. It can be seen from the formula (2) that when nitrous acid is decomposed to form NO, a small amount of nitric acid is also generated, and NO is oxidized to NO2 in the air, and further reacts with water to form nitric acid. NO+O2→NO2 (4) NO2+ H2O→ HNO2+HNO3 (5) As shown in the formulas (4) and (5), not only the nitroso group is oxidized to form nitric acid, but also the formation of nitroso myoglobin is inhibited. Nitric acid has a strong oxidation effect, and even if the meat contains a strong reducing substance, it cannot prevent partial oxidation of myoglobin to high iron myoglobin. Therefore, in the use of nitrates and nitrites, reducing substances such as L-ascorbic acid and its sodium salts are often used to prevent myoglobin oxidation, and oxidized brown high-iron myoglobin can be reduced to red reduced muscles. Red protein to help hair color. In addition, nicotinamide can bind to myoglobin to form a very stable nicotinamide myoglobin, which is difficult to be oxidized. Therefore, adding proper amount of nicotinamide during the curing process of meat products can prevent myoglobin from nitrous acid to Oxidation discoloration during the formation of nitroso groups. If L-ascorbic acid or isoascorbic acid and its sodium salt and nicotinamide are used together in the curing process of meat products, the color development effect is better and can be maintained for a long time without fading. Cleaner Products,Toilet Bowl Cleaner Liquid,Toilet Block Cleaner,Stain Remover Cleaning Wuxi Keni Daily Cosmetics Co.,Ltd , https://www.kenidailycosmetics.com