Irradiation from radioactive elements, such as cobalt-60, or an electron beam, can be applied to raw materials to prevent the proliferation of plagues or to kill bacteria that could be present in ready-to-eat foods or industrialised ingredients. It is therefore an important tool in food safety and food security. Food contamination by some pathogenic bacteria, such as Salmonella sp. or Escherichia coli, is still a recalcitrant problem faced by the food industry, even in countries where the highest quality control measurements are applied. The present paper is intended to be an overview on the roles of irradiation treatment on different sectors of the food industry with a focus on relevant aspects such as food contamination risks, the irradiation process itself and public concern about new technologies.