Other names for the additive (synonyms)
General information
The food additive E332(i), known as potassium dihydrocitrate, is a subtype of the additive E332 (potassium citrates), which is used in the food industry as an acidity regulator, stabilizer, and buffering agent.
Unlike the subtype E332(ii), in the molecule of additive E332(i) only one hydrogen atom of citric acid is replaced by a potassium ion. This results in a more pronounced acidic character of the compound and determines its specific technological properties as an acidity regulator and buffering agent.
The chemical formula of additive E332(i) is KH2C6H5O7 (or KC6H7O7).
The main difference of this form from other potassium citrates is the ability of the additive to act as a powerful buffering agent specifically in an acidic range. Additive E332(i) has moderate hygroscopicity and excellent solubility in water, and its aqueous solutions have a lower pH value than the trisubstituted form (E332(ii)), which is critical for certain technological processes.
Industrial production of additive E332(i) is based on the reaction of partial neutralization of citric acid. The main difference in the production of this subtype lies in the precise control of the amount of potassium hydroxide (KOH) or potassium carbonate (K2CO3): the reaction is stopped at the stage of formation of the monosubstituted salt.
In the food industry, potassium dihydrocitrate is mainly used as an acidity regulator in products where it is necessary to preserve or delicately adjust an acidic environment. Thanks to its buffering properties, it ensures pH stability without sharp changes in the flavor profile.
In addition, additive E332(i) can act as a synergist of antioxidants, enhancing the effect of ascorbic acid, particularly in processed fruits and vegetables.
In the production of beverages and dry mixes, monopotassium citrate is used in fruit drinks, instant teas, and desserts, where it is important to emphasize the sour taste while ensuring system stability during storage.
In the confectionery industry, additive E332(i) plays an important role in the production of jelly, marmalade, and jams. It regulates the acidity level required for optimal pectin gelation, which directly affects the texture, consistency, and stability of the final product.
For more details on the general properties of potassium citrates, their effects on the human body, and references to scientific studies, see the main article on the food additive E332.