Citric acid (CA), also known as citric acid, molecular formula is C6h8o7 is an important organic acid, colorless crystal, odorless, has a strong sour taste, easily soluble in water, is an acidity regulator (GB2760- 2014) and food additives.

Synthetic citric acid is obtained by fermenting sugar-containing substances such as sugar, molasses, starch, and grapes.Divided into anhydrous citric acid and monohydrate citric acid