Food processing using ionizing radiation

Röntgen's discovery of X-rays in 1895 enabled Minck, in 1896, to demonstrate the bactericidal activity of ionizing radiation, but it wasn't until the 1950s that this property found industrial application in sterilization methods.

Ionization is a physical process using the characteristics and properties of ionizing radiation. Radiation is said to be ionizing if it has sufficient energy to create ions within the irradiated matter. Unlike other types of radiation, such as infrared rays and microwaves, ionizing radiation is almost totally absorbed by the electronic structure of the irradiated material. As a result, they can cause more significant chemical changes.

In living matter, ionizing radiation breaks the chain of deoxyribonucleic acid (DNA) or the strand of ribonucleic acid (RNA), destroying bacteria, yeasts, molds and fungi, as well as viruses by preventing their multiplication. This method also improves food preservation by inhibiting germination. Many studies have verified the effectiveness of ionization treatment in extending the shelf life of food products. To date, however, the technique has been little used. There are two main reasons for this: the lack of information available to consumers, and the limited number of products authorized for treatment (see in ).

What's more, since September 2000, a new directive has made it compulsory to label products treated with ionizing radiation. This directive is positive for the consumer, who will be warned, but frightens producers who, for the sake of simplicity, have chosen to change treatment techniques.

Food irradiation, after making progress following the recommendation of this technique by the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO), is now in decline, following the introduction of mandatory labelling.

Nearly a million tonnes of food are routinely treated with ionizing radiation in 41 countries to eliminate harmful bacteria, extend shelf life and destroy insects.

Ionization has also made it possible to tackle other important fields such as sterilization, improving food preservation and modifying plastics and textiles.