乳酸简介：

名称：乳酸

英文名：Lactic acid；2-Hydroxy propionic acid

其它名称：2-羟基丙酸；α-羟基丙酸；丙醇酸

CAS号：50-21-5

分子式：C3H6O3

结构简式：CH3CH(OH)COOH

纯品为无色液体 ，工业品为无色到浅黄色液体。无气味，具有吸湿性。相对密度1.2060(25/4℃)。熔点18℃。沸点122℃（2kPa)。折射率nD(20℃)1.4392。能与水 、乙醇 、甘油混溶，水溶液呈酸性，PKa=3.85。不溶于氯仿 、二硫化碳 和石油醚 。在常压下加热分解，浓缩至50%时，部分变成乳酸酐，因此产品中常含有10%～15%的乳酸酐。由于具有羟基 和羧基 ，一定条件下，可以发生酯化反应，产物有三种

本品为无色透明粘性液体、微酸性，有引湿性，水溶液显酸性反应。与水、乙醇或能任意混合，在氯仿中不溶。

乳酸有很强的防腐保鲜功效，可用在果酒、饮料、肉类、食品、糕点制作、蔬菜 ( 橄榄、小黄瓜、珍珠洋葱 ) 腌制以及罐头加工、粮食加工、水果的贮藏，具有调节 pH 值、抑菌、延长保质期、调味、保持食品色泽、提高产品质量等作用

Introduction to Lactic acid:

Name: Lactic acid

Lactic acid; 2-Hydroxy propionic acid

Other names: 2-hydroxypropionic acid; Alpha-hydroxy propionic acid; Propyl alcohol acid

The CAS number: 50-21-5

Molecular formula: C3H6O3

Structure simple: CH3CH(OH)COOH

Pure products are colorless liquid, industrial products are colorless to light yellow liquid. No odor, hygroscopicity. Relative density 1.2060(25/4℃). Melting temperature 18 ℃. Boiling point 122℃ (2kPa). Refractive index nD(20℃)1.4392. It can be miscible with water, ethanol and glycerol, and the water solution is acidic, PKa=3.85. Insoluble in chloroform, carbon disulfide and petroleum ether. When heated and decomposed under normal pressure and concentrated to 50%, part of the product becomes lactic anhydride, so the product often contains 10% ~ 15% lactic anhydride. Due to the presence of hydroxyl and carboxyl groups, esterification reactions can occur under certain conditions, and there are three kinds of products

This product is colorless transparent viscous liquid, slightly acidic, hygroscopic, aqueous solution acid reaction. Can be mixed with water, ethanol or ethyl ether arbitrarily, insoluble in chloroform.

Lactic acid has a strong antisepsis effect, can be used in wine, beverage, meat, food, confectionery, vegetables, olives, cucumber, pearl Onions) canning and fruit processing, food processing, storage, has antibacterial, adjust pH value, prolong the shelf life keep food, flavor, color, improve product quality, and so on