Food preservative - Boric acid

Boric acid and sodium tetraborate (borax) are authorized in EU for use as preservatives of sturgeon eggs (caviar) up to a maximum concentration of 4 g boric acid/kg.

Boric acid (also known as boracic acid or orthoboric acid) and borax are common boron-containing compounds. It mainly exists in the form of borates, compounds formed after combining with other substances, in the environment. Boric acid exists in the form of colorless crystals or a white powder that dissolves in water.

Boric acid and borax have long been used as additive in various foods. Since boric acid and borax are effective against yeasts, and to a much lesser extent, against moulds and bacteria, they can be used to preserve food products.

It was reported that boric acid to be used as food preservatives in some foods and food products. Boric acid is used for preserving meats, meat products, caviar and dairy products.

Boric acid is detrimental to human health if consumed in excess. In 1990, the SCF (Scientific Committee for Food) evaluated boric acid and concluded that boric acid and its salts were toxicologically acceptable for use only as a preservative in genuine caviar.

Because of boric acid contains cumulative toxicity, FAO/WHO Expert Committee declared that boric acid is unsafe to use as food additives. The evaluation noted that a long-term study in rats had demonstrated some accumulation of boric acid in some organs. The evaluation also reported that the compound is nephrotoxic.
Food preservative - Boric acid

Boric acid as food additive

Boric acid (H3BO3) is a colorless, odorless compound available as crystals, granules an as a white powder. 

Boric acid acts by blocking enzymes in the phosphate metabolism. Boric acid is the most common of the borates, which are compounds of boron, oxygen and other elements.

The action of boric acid is directed mainly against yeasts, its inhibitory action against molds is very slight, while that against bacteria is only partial and leaves some strains completely unaffected.

Boric acid long retained great importance in Europe as a preservative for margarine and butter.

The maximum allowed amount of boron as a food additive by the US Food and Drug administration is 310 ppm.

At higher concentration, boric acid accumulates in adipose tissue and especially in the central nervous system.

Acute exposure to boric acid in liquid or solid forms can cause irritation, the severity of which is determined by the concentration and duration of exposure.
Boric acid as food additive