Other names for the additive (synonyms)
General Information
The food additive E332, known as potassium citrates (potassium salts of citric acid), belongs to the group of acidity regulators, stabilizers, and chelating agents. In the food industry, E332 helps control pH, stabilize texture, and improve product shelf life.
Potassium citrates are salts of citric acid. Their natural origin is confirmed by their presence in many plant-based foods (citrus fruits, berries, coniferous plants, and other fruits). In living organisms, potassium citrates are natural metabolites that participate in cellular respiration as intermediate compounds in the Krebs cycle, supporting energy production at the cellular level.
The history of potassium citrates began in 1784 when Swedish chemist Carl Wilhelm Scheele first isolated citric acid. Large-scale production became possible in 1893 благодаря microbiological synthesis, and by the late 19th to early 20th century, E332 began to be used in the food industry.
Potassium citrates can exist in two main forms depending on the degree of hydrogen substitution in citric acid:
- E332(i) — potassium dihydrogen citrate (monosubstituted citrate), chemical formula — KC6H7O7;
- E332(ii) — tripotassium citrate (trisubstituted citrate), chemical formula — K3C6H5O7.
Potassium citrates are a white crystalline powder or granules, highly soluble in water and practically insoluble in organic solvents. The additive E332 has a mildly salty-sour taste and moderate hygroscopicity, meaning it can absorb moisture from the air.
The production of E332 has evolved from simple fruit processing to advanced biotechnological synthesis, ensuring its global availability. Traditionally, it was produced by neutralizing citric acid obtained from citrus fruits with potassium salts, making the industry dependent on climate and seasonal yields.
Today, microbiological methods dominate: specific strains of mold fungi Aspergillus niger convert sugar-based raw materials into citric acid with high efficiency. The resulting acid is then neutralized with potassium hydroxide (KOH) or potassium carbonate (K2CO3), allowing precise synthesis of both dihydrogen citrate (E332i) and tripotassium citrate (E332ii).
Effects on the Body
Benefit of Additive E332
Although potassium citrates are not formally classified as nutrients, their components — potassium ions and citrate groups — play active roles in human metabolism.
Scientific data confirm that potassium acts as a physiological antagonist to sodium, making adequate intake essential for maintaining normal blood pressure.
Studies show that potassium citrates help counteract the negative effects of excessive salt intake by promoting sodium excretion and improving vascular tone. This mechanism also helps reduce fluid retention and swelling associated with high-sodium diets.
Clinical studies indicate that potassium citrates are effective in preventing kidney stones and treating urolithiasis, especially calcium oxalate stones. This is due to their ability to alter the physicochemical properties of urine, particularly by increasing its pH, and directly inhibiting crystallization processes.
Additionally, according to other scientific data, the systemic alkalizing effect of citrates helps maintain acid-base balance, which may slow calcium loss from bone tissue and support musculoskeletal health.
Risks of Additive E332
Potassium citrates are well metabolized in the body and excreted naturally (like other potassium salts and citrate via urine and respiration).
Research indicates that consuming large doses of potassium citrates on an empty stomach or in concentrated form may irritate the gastrointestinal mucosa, leading to symptoms such as nausea, abdominal pain, diarrhea, or general digestive discomfort.
According to clinical data, excessive potassium intake combined with potassium-sparing diuretics or ACE inhibitors may increase the risk of hyperkalemia — a potentially dangerous elevation of potassium levels in the blood.
The Joint FAO/WHO Expert Committee on Food Additives (JECFA) and the European Food Safety Authority (EFSA) have recognized E332 as safe for use in food products at typical consumption levels. The acceptable daily intake (ADI) is classified as “not specified” due to the lack of evidence of adverse effects at normal intake levels.
Uses
In the food industry, E332 is valued for its multifunctionality and its ability to gently adjust physicochemical properties without significantly altering taste.
As an effective acidity regulator and buffering agent, E332 is widely used in soft drinks, confectionery, and powdered milk, where maintaining a stable pH is essential for shelf life.
In the dairy industry, E332 acts as a stabilizer, preventing protein coagulation during pasteurization or sterilization. Due to its emulsifying properties, it is also an important ingredient in processed cheese production, ensuring a uniform texture and preventing fat separation.
Additionally, thanks to the high bioavailability of potassium, E332 is commonly used in functional foods and isotonic drinks to help restore electrolyte balance.
Legal Status
E332 is approved for use in the European Union under Regulation (EC) No 1333/2008 and is included in the list of permitted food additives with specified functions and conditions of use.
In the United States, potassium citrates are classified by the FDA as GRAS (Generally Recognized As Safe), meaning they are permitted without specific restrictions.
E332 is also approved in Ukraine and many other countries, where it is used in accordance with local food safety regulations.