Disodium Citrate

Disodium Citrate (CAS Number: 144-33-2) is a chemical compound derived from citric acid, a naturally occurring organic acid found in citrus fruits. Specifically, it is a disodium salt of citric acid, meaning it is formed when two of the three acidic hydrogen atoms in citric acid are replaced by sodium ions. Chemically, it is represented as C6H6Na2O7. It typically appears as a white, crystalline powder or granular substance that is highly soluble in water.

Disodium citrate belongs to a group of compounds known as sodium citrates, which also includes monosodium citrate and trisodium citrate. These compounds are produced through the neutralization of citric acid with a sodium-containing base, such as sodium hydroxide or sodium carbonate. Due to its chemical structure, Disodium Citrate exhibits properties that make it valuable in food applications, including its ability to buffer pH, chelate metal ions, and contribute to desired textural characteristics.

Disodium Citrate serves multiple functions in the food industry, primarily as a stabilizer and thickener, but also as an emulsifier, pH regulator, and chelating agent. Its versatility makes it a common ingredient in a wide array of processed foods and beverages:

* **Stabilizer and Thickener**: In dairy products such as milk, yogurt, and processed cheeses, Disodium Citrate helps prevent protein coagulation and separation, ensuring a smooth, consistent texture. It contributes to the thickening effect in sauces, desserts, and canned goods, improving their mouthfeel and stability over time.

* **Emulsifier**: It aids in blending ingredients that typically separate, such as oil and water. This emulsifying property is particularly useful in products like cheese spreads, processed meats, and dressings, where it helps maintain a homogenous mixture and prevents fat separation.

* **pH Regulator (Buffering Agent)**: Disodium Citrate helps control and maintain the pH level of food products. This is critical for several reasons: it can inhibit the growth of undesirable microorganisms, thereby extending shelf life; it can influence the flavor profile of a food; and it can optimize the effectiveness of other ingredients. It is often used in beverages, jams, jellies, and confectionery to achieve a desired acidity.

* **Chelating Agent**: It can bind to metal ions, preventing them from reacting with other food components and causing undesirable changes like oxidation, discoloration, or flavor deterioration. This property is beneficial in preventing rancidity in fats and oils and maintaining the color of fruits and vegetables in processed foods.

Examples of food products where Disodium Citrate might be found include evaporated milk, condensed milk, powdered beverages, ice cream, jams, jellies, fruit preparations, and various processed convenience foods.

The safety of Disodium Citrate in food applications is generally well-established, largely owing to its close relationship with citric acid, a ubiquitous compound in nature and a common food ingredient. Citric acid and its salts are extensively metabolized in the human body as part of the normal metabolic cycle (Krebs cycle) and are readily excreted.

Regarding formal safety assessments: the Joint FAO/WHO Expert Committee on Food Additives (JECFA) has evaluated sodium citrates (which include monosodium, disodium, and trisodium citrate) and assigned them an "acceptable daily intake (ADI) not specified." This classification is typically given to substances of very low toxicity, where the total daily intake through food and water does not pose a health risk, implying that there is no need to establish a numerical ADI.

The European Food Safety Authority (EFSA) has also assessed sodium citrates (E 331) and reaffirmed their safety. EFSA's re-evaluation confirmed that there is no safety concern for sodium citrates when used as food additives at currently authorized uses and levels.

For AdditiveFacts.com, it is important to note that the FDA's database for "Adverse Events" and "Recalls" shows 0 reported incidents specifically linked to Disodium Citrate (CAS Number: 144-33-2). While Disodium Citrate is not individually listed as FDA GRAS (Generally Recognized As Safe) under its specific CAS number, sodium citrates as a broader category (e.g., 21 CFR 182.1748 for Sodium Citrate) are listed as GRAS by the FDA. This indicates that while an individual, specific GRAS notification might not exist for *disodium citrate* alone, its use falls under the general understanding of sodium citrates as safe food ingredients, particularly given their common metabolic pathways in the body.

Overall, the available scientific evidence and regulatory assessments indicate that Disodium Citrate is safe for consumption at levels typically found in food products.

In the United States, Disodium Citrate is used in food under the broad umbrella of "sodium citrates." While the specific CAS number for Disodium Citrate (144-33-2) might not have an individual FDA GRAS (Generally Recognized As Safe) notification in the public database, its close chemical relationship to citric acid and other sodium citrates, which *are* recognized as safe by the FDA (e.g., 21 CFR 182.1748 for Sodium Citrate), supports its use. Food manufacturers may also rely on a self-GRAS determination based on scientific procedures for such ingredients.

In the European Union, Disodium Citrate is authorized for use as a food additive under the E-number E 331, which covers all sodium citrates (monosodium citrate, disodium citrate, and trisodium citrate). It is approved for use in a wide range of food categories according to specific maximum levels or quantum satis (meaning no maximum numerical level is specified, allowing use at levels necessary to achieve a particular technological effect, provided it does not mislead the consumer).

Other international bodies, such as JECFA, have also affirmed the safety of sodium citrates, providing a global consensus on their acceptability in food.

Given that Disodium Citrate is a well-established food additive and a salt of a highly common natural compound (citric acid), extensive specific toxicity studies for *Disodium Citrate* alone are often not deemed necessary in modern regulatory contexts, particularly when its parent acid and other salts are thoroughly evaluated. Safety assessments tend to focus on the broader class of citrates due to their shared metabolic fate.

Key studies and evaluations supporting the safety of Disodium Citrate (as part of sodium citrates) include:

* **JECFA Evaluations**: The Joint FAO/WHO Expert Committee on Food Additives (JECFA) has conducted multiple evaluations of citric acid and its salts. Their conclusions consistently assign an "ADI not specified" for sodium citrates, indicating a very low level of toxicity and no identifiable health risk at typical consumption levels.

* **EFSA Re-evaluations**: The European Food Safety Authority (EFSA) completed a re-evaluation of food additives including sodium citrates (E 331) in 2013 and subsequent updates. These comprehensive assessments reviewed all available toxicological data, exposure data, and metabolism studies. EFSA concluded that there was no safety concern for sodium citrates when used at the authorized levels as food additives.

* **Metabolic Studies**: Research on the metabolism of citric acid and citrates consistently shows that they are fully metabolized in the body as part of the Krebs cycle, a central pathway for energy production in nearly all living cells. They are converted into carbon dioxide and water, demonstrating efficient biological processing without accumulation or adverse effects at normal intake levels.

While direct studies detailing adverse events of Disodium Citrate are scarce, this absence is generally interpreted as a testament to its safety profile, rather than a lack of data, especially given the extensive body of research on citric acid and its various salts. The regulatory bodies base their conclusions on a holistic view of chemical structure, metabolic fate, historical use, and available toxicological data for the class of compounds.