Sodium phosphate (E339)

Salts derived from sodium hydroxide and phosphoric acid are collectively called sodium phosphates. This nutritional supplement is completely synthetic and does not occur in nature in any form.

In food, it is most commonly used as an antioxidant and preservative, although it also has emulsifier and stabilizer properties. In addition, the substance also acts as an acidity regulator, as it affects the establishment and maintenance of a certain level of acidic environment in the product. It also has a moisture-retaining effect.

Having met the E339 code in the composition of the selected food, the buyer can determine for himself that the product has been treated with sodium phosphates, and decide whether it is worth buying and using it. According to international standards and norms, the substance belongs to food additives of a low degree of danger.

Methods for obtaining sodium phosphates in the laboratory

To date, there are several technologies for the extraction of sodium phosphates: using thermal phosphoric acid, superphosphate or acid obtained by the sulfuric acid method.

One of the methods involves carrying out a neutralization reaction of 25% phosphoric acid with a solution of soda ash. The resulting mixture is filtered, evaporated to a certain density and crystallized. If phosphoric acid has a saturation of more than 40%, the neutralization reaction is carried out at a temperature of 85-95 degrees Celsius.

Superphosphates are treated with sodium sulfate solution. The resulting substance is monosodium phosphate, which is filtered in an acidic solution from the insoluble residue and the released calcium sulfate, and then also evaporated or granulated in a spray dryer.

Chemical properties of a substance

The additive is in the form of a white powder in granules or crystals. It is not sensitive to thermal effects and is highly soluble in water.

Substance E339 is used as a thickener, as it has the property of regulating the viscosity of the mixture, improving its texture. As a stabilizer, the E339 additive is involved in the formation of the consistency of the product, contributes to its improvement and preservation unchanged, protects food from burning during heat treatment. Also, sodium phosphates have found their use as emulsifiers, since one of their properties is the ability to create mixtures together with initially immiscible substances, for example, a mixture of oil and water.

Varieties of food additive

In the food industry, these types of sodium phosphates are commonly used;

• sodium orthophosphate 1-substituted (E339i);
• sodium orthophosphate 2-substituted (E339ii);
• 3-substituted sodium orthophosphate (E399iii).

Their chemical formulas differ from each other, but the substances have a similar effect. Therefore, if you see one of these designations on the packaging of a product, you can be sure that sodium phosphates were used in it.

Application in production

The main purpose of the substance is to improve the properties of food products, therefore the food industry is the main “consumer” of this component. It can be found in the compositions:

• bakery and confectionery products;
• dairy products and milk powder;
• soft drinks;
• dry soups, sauces, pastes, bouillon cubes and other instant products;
• cheeses and processed cheeses;
• meat and fish products;
• dry baking powder and baking mixes;
• biscuits and cakes.

Especially often it is found in sausages and sausages, meat and fish: the substance works as a moisture-retaining component, therefore, in this way it is possible to preserve products without loss of moisture and, accordingly, weight.

In addition, until the 1960s, it was widely used in the production of detergents and powders. However, due to the excessive ingress of nitrogen and phosphorus compounds into water bodies, the quality of waste water, which further enters water pipes and is released into the natural environment, began to deteriorate significantly, which could harm the aquatic ecosystem. For this reason, restrictions and prohibitions on the use of the substance in such products began to appear, and today they are practically not used in the manufacture of powders and detergent products.

Sodium phosphates are also used in the pharmaceutical industry – they are added to laxatives, since the substance has the appropriate effect at a certain dosage.

Impact on the human body, possible harm from use

The laxative effect of the substance is known to both physicians and chemists. Products that contain it in their composition should be present in the human diet in a limited amount so as not to provoke a corresponding reaction of the digestive tract.

As for other possible dangers of the E339 food additive, these include the likelihood of diseases of the gastrointestinal tract: gastritis, ulcers, pancreatitis. However, to date, the relationship between substance use and these disorders has not been officially confirmed.

The results of studies conducted on laboratory animals indicate that sodium phosphates contribute to the disruption of calcium absorption in the body, its leaching from bone tissue and tooth enamel.

In some cases, detergents and powders containing E339 cause allergic reactions in the form of skin rashes and redness.

In children, the use of products with this component in the composition can cause nervous disorders: impaired concentration, aggression, anxiety, hyperactivity, motor anxiety. For them, the amount of food with the addition of E339 should be limited.

According to some unconfirmed reports, sodium phosphates have an oncogenic effect, that is, they can cause oncological diseases of the digestive tract. Other than a possible therapy for constipation, nothing is known to date about the benefits of the substance for human health.

While manufacturers are on the path to reduce the cost of food products, additives with the “E” code, including E339, will be indicated on the labels of a variety of foods. The component is used as an anti-caking agent, emulsifier, antioxidant and thickener: with its help, it improves the taste and texture characteristics of food, while it is a cheap and profitable ingredient for manufacturers.

Sodium phosphates are substances with an extremely low level of danger to humans, their use is permitted in Ukraine, Russia and the countries of the European Union. In addition to the threat of a violation of calcium metabolism in the body, no other information about possible harm to health has yet been officially confirmed. Nevertheless, research on the effects of sodium phosphates on humans continues today.