With preservatives, foods last longer and are safe.

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Preservatives are still needed to ensure the safety and variety of different foods available. They carry out an action of slowing down the deterioration of food and prevent any alteration of taste or appearance. The evaluation and use of these substances in food are strictly controlled at both European and international level.

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Why is food stored?

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Conservation is usually defined as a method used to maintain an existing condition or prevent deterioration that can be caused by:

chemical (oxidation), physical (temperature, light) or biological (microorganism) factors.

Thanks to the storage it was possible to have food from one crop to another. The main function of this process is therefore to delay the deterioration of food and to prevent changes in taste or, in some cases, appearance.

It can be carried out in different ways, by processing methods including canning, dehydration (drying), smoking and freezing, the use of packaging and the use of food additives as antioxidants or other preservatives.

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In this article, we will focus on preservatives.

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The use of preservatives is the main motivation for the need to make food safer by eliminating the influence of biological factors.

The most serious threat to consumers is that of foods that have gone bad or become toxic as a result of the microorganisms (e.g. bacteria, yeasts, mould) contained in them. Some of these organisms can sew poisonous substances ("toxins"), which are dangerous to human health and can even be lethal.

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How do you store food and what substances are used?

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To delay the deterioration of food due to microorganisms, anti-microbial substances are used that inhibit, delay or prevent the growth and proliferation of bacteria, yeasts and mould. To inhibit the growth of bacteria e.g. in wine, dried fruits, vegetables, vinegar or brine, sulfur-based compounds such as sulphites (E221-228) are used.

Sorb acid (E200) can be used for many different purposes, including the preservation of potato products, cheese and jam. Another important group of substances is nitrate and nitrite compounds (E249-252). They are used as additives in meat products such as sausages and hams to protect them against the botulism-causing bacterium (Clostridium botulinum), thus making a significant contribution to food safety. Benzoic acid and its calcium, sodium or potassium salts (E210-213) are used as antibacterials and fungicides in foods such as pickled cucumbers, low-sugar jams and jellies, seasonings.

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Examples of preservatives widely used in the EU:

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E200-203 Compounds based on ascorbic acid and sorbate

Cheese, wines, dried fruits, fruit sauces, glazes.

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E210-213 Benzoic acid, and benzoate

Pickled vegetables, low-sugar jams and jellies, candied fruit, semi-preserved fish products, sauces.

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E220-228 Sulphur dioxide and sulphite compounds

Dried fruits, preserved fruits, potato products, wine.

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E 235 Natamicyn

Superficial treatment of cheese and sausages.

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E249-252 Nitrite and nitrate compounds

Sausages, bacon, ham, foie gras, cheese, pickled herring.

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The need for controls and labelling

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In order to ensure that preservatives actually contribute to greater food safety, the use of these substances is subject to a safety assessment and authorisation procedure before placing on the market.

 

At European level, the bodies responsible for assessing the safety, authorisation, control and labelling of preservatives and other additives are the European Food Safety Authority (EFSA) and the European Commission, Parliament and Council. Internationally, there is a Joint Expert Committee on Food Additives (JECFA) of the Food and Agriculture Organization (FAO) and the World Health Organization (WHO).

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The evaluation of the safety of preservatives, as in the case of other food additives, is based on the examination of all available toxicological data, including observations in humans and animal models.

On the basis of the available data, a maximum level of additive is established which has no demonstrable toxic effect. It's called the 'no-observed-adverse-effect level' (NOAEL) and is used to determine the 'Acceptable Daily Intake' (ADI) for each additive.

The ADI provides for a wide margin of safety and refers to the amount of food additive that can be taken daily, over a lifetime, without adverse effects on health.

The authorization and conditions of use of preservatives are regulated by Directive 95/2/EC of the European Parliament and of the Council of 20 February 1995 on food additives other than colours and sweeteners.

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At the public level, there have been many concerns that some food additives may cause negative reactions, although accurate surveys show that they are mainly based on misconceptions rather than identifiable negative reactions. Proven cases of real allergic (immunological) reactions caused by preservatives are rare.

Food additives for which adverse reactions have been reported include preservatives in the solfitant group, which include various inorganic sulphidizing additives (E220-228), and benzoic acid and its derivatives (E210-213), which can trigger asthma characterized by breathing difficulties, shortness of breath, runny nose and cough in sensitive subjects (e.g. asthmatics).

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The European Parliament, together with the European Council, has established a detailed labelling system for food additives, to allow consumers to make conscious choices. The law also provides that additives are indicated on the packaging of food products divided by category (preservative, colour, antioxidant, etc.) with their name or with the number preceded by the letter E that distinguishes them.

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