Status of use of preservatives and criteria for their use(1)

It has a sustained inhibitory effect on the growth of micro-organisms that use spoilage substances as metabolic substrates. It is important that it inhibits the most susceptible to spoilage under different circumstances and has a sustained effect especially when the general sterilisation effect is not sufficient. For the preservation of fibres and wood mineral oil, coal tar, tannin, for biological specimens formaldehyde, ascorbic acid, toluene, butyl paraben, nitrofurazone derivatives or balsam resins are used. 

The use of preservatives in foodstuffs is restricted and therefore relies mostly on some physical methods such as drying and curing. Special preservatives include organic acids such as acetic acid, vegetable oils with oleic acid lipids as components, and special essential oil components such as mustard seeds. For the localisation of organisms (e.g. on the surface of the body or in the digestive tract), various preservatives (e.g. iodoform, benzyl salicylate, aniline dyes or acridine colours) can be used depending on the specific conditions.

Only 32 food preservatives are approved for use in China, and they are all low-toxicity and high-safety varieties. They have undergone extensive scientific experiments, animal feeding and toxicological testing and identification before being approved for use, and have been proven not to cause any acute, sub-acute or chronic harm to humans. As long as the variety, quantity and range of food preservatives used by food manufacturers are strictly controlled within the scope of the National Standard for the Use of Food Additives (GB2760-2011), they are absolutely harmless to human health and can be consumed with confidence. For example, preservatives such as potassium sorbate and sodium benzoate are usually added to food products found in the market, and these two most widely used preservatives are generally excreted in urine and do not accumulate in the body after ingestion.

In China, the majority of preservatives used in food production are synthetic and can have certain side effects when used improperly; some preservatives even contain trace amounts of toxins, which can cause certain damage to human health when ingested in excess over a long period of time. The use of benzoic acid, a widely used food preservative, for example, has been controversial internationally. For example, because of reports of poisoning from the accumulation of benzoic acid and its sodium salt, the European Community Child Protection Group considers it inappropriate for use in children's food, and Japan has placed strict restrictions on its use. Even sorbic acid and potassium sorbate, which are internationally recognised as safe preservatives, can affect the metabolic balance of the body when consumed in excess.

The Hygienic Standard for the Use of Food Additives strictly stipulates the types of preservatives, quality standards and the amount of additives, but it is very regrettable and extremely worrying that many food manufacturers have violated, illegally and indiscriminately used and abused food preservatives in a very serious way. It is mainly manifested in the following three aspects.

(1) the use of large doses of preservatives.

(2) The use of cheap but toxic preservatives.

(3) The use of spoiled animal meat as sausages and the use of formalin as a preservative in order not to affect the appearance of the sausage and to cover up the truth of spoilage.