Food irradiation

At this stage, it should be noted that almost invariably the desired effect of irradiation of foods can also be attained by other standard methods, such as heat 

Chapter 11 Radiation Chemical Applications in Science and Industry 

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Chemical synthesis is one important aspect of the application of radiation-chemical reactions in industry. Various kinds of radiation-induced syntheses are available, some of which will be described here. There are also nonsynthetic applications including, but not limited to, food irradiation, waste treatment, and sterilization by irradiation. Some of these will be taken up in the next section. 

Some 40 countries have cleared irradiated foods of certain types for human consumption, or have given provisional clearance. Large scale ( 104 tons per year) irradiation of potatoes has been approved in Japan, and very large scale ( 105 tons per year) irradiation of grains has been reported from the former Soviet Union for insect control. However, it must be admitted that clearances with associated legal complications have come slowly in most countries, and even today there are ongoing debates regarding the ethics and economics of food irradiation. 

International Atomic Energy Agency (1968), Manual of Food Irradiation Dosimetry, Technical Report 178, Vienna. 

Possible industrial applications include screening of substances with antiradical activity, quality testing of raw materials, pharmaceuticals, cosmetic products, fruit juices, wines, beers, edible oils, detection of food irradiation, and many more. 

With the exception of ethylene vinyl acetate added in the 1980 s, the list of materials and polymers approved as packaging for food irradiated products has remained static for decades. This article supplies details of the approved list, which includes such polymers as polyethylene terephthalate and polyvinyl chloride. The article provides an update on the latest proactive move to expand the list of packaging materials and polymers approved for the irradiation of foods. The expanded list would include ethylene vinyl alcohol, PVC film, ionomers, nylon 66, 6/12 and copolyesters among others. 

The National Centre for Food Safety Technology, is spearheading several packaging related efforts to expand the fist of polymers that can be used for packaging in food irradiation applications. This comprehensive article explains and describes the current situation in the field of irradiated foods and packaging and provides an update on impending approval for processed and red meats. The industry is concerned to uphold and maintain public confidence in the processed food and irradiated food supply. 

Radioactive devices used for food irradiation in industry... 

Work programme of CEN TC 275 Working Group 8 Food irradiation... 

The economic scale of the application of radiation in the field of agriculture in Japan was estimated from public documents to be about 964 million in 1997. The economic scale survey in food irradiation and mutation breeding was extended to the United States for a direct comparison to the situation in Japan. The maximum estimation amounted to 3.2 billion for food irradiation and 11.2 billion for mutation breeding. The economic scale for products in selected agricultural fields was 14.5 billion for the United States and about 0.8 billion for Japan, implying that the former is larger in magnitude by a factor of about 18 [5]. 

Other kinds of ionizing radiation, in some respect, do not suit the requirements of food irradiation. Except for difference in penetrability, electromagnetic ionizing radiations and accelerated electrons are equivalent in food irradiation and can be interchangeably used. 

Food irradiation is a very complex topic and has an enormous literature. Apart from thousands of journal articles and proceedings of large number of international conferences and panel meetings, its state of the art has been extensively reviewed during the course of decades by a number of noteworthy books [1-5]. The present brief chapter mainly focuses on the principles and some potential applications of food irradiation and refers to some most recent research and developments in these regards. 

Two basic types of radiation sources can satisfy the requirement of industrial use of food irradiation ... 

Machine sources such as electron accelerators and those converting accelerated electron beams to x-ray photons. Accelerated electrons have low penetrability. Thus they cannot meet all the goals of food irradiation. The 10 MeV electrons, the highest energy level of electron irradiation presently recommended by the Codex Alimentarius [6], can penetrate food with typically about 4-cm thickness. 

The technological feasibility of a food irradiation treatment depends on how much irradiation the food withstands without adversely changing its qualities, i.e., how much useful effect can be achieved without significant change to the chemical composition, nutritional value, and sensory properties of the product. Generally, there is a minimum dose requirement. Whether every mass element of a food requires irradiation will depend... 

Minerals and trace elements cannot be affected under the process conditions of food irradiation. 

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