Food irradiation applications

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. 

Proper control of food irradiation applications should fulfill the requirements for both food technologies and radiation technologies. Application of well-established methods for measurement of absorbed radiation dose and the dose distribution helps to provide assurance that the radiation treatment is both effective and legally correct [133]. Computer tomography (CT) can provide detailed, high-resolution, and accurate dose maps for any arbitrary product and package configurations [134]. Such dose maps are an essential part of process validation. 

The dichromate dosimeter solution is of importance mainly for radiation sterilization and food irradiation applications both for gamma and electron dosimetry. Due to its very good reproducibility, the system is classified as a reference standard system (ASTM E 2628-2009) in the 5-50 kGy dose range and used widely also as a transfer standard dosimeter. 

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. 

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. 

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]. 

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. 

Presently, irradiation of spices is the most widely utilized application of food irradiation that is practiced in more than 20 countries, including Argentina, Belgium,... 

Besides the pioneering implementations of specific low-dose applications as well as the widely utilized irradiation of spices now, mentioned in Secs. 4.1, 4.2, and 4.9, small-scale commercial application of irradiation to ensure hygienic quality of food, especially those of animal origin, has been carried out in Chile, China, Indonesia, and Thailand in the past two decades. In the recent years, new commercial irradiators including some that are dedicated to food irradiation have been commissioned in Brazil (which plans to add up to 10 facilities in the coming years), China, India, Republic of Korea, Mexico, and Thailand [157]. 

Food Irradiation Principles and Applications Molins, R., Ed. Wiley-Interscience New York, 2001. 

HPhe radiation preservation of fresh fruits and vegetables has received considerable attention as one of the promising applications for food irradiation. As with most other applied aspects of food irradiation, however, the process is not without complications. This paper is concerned only with the effect of gamma radiation upon fresh commodities, drawn principally from work conducted at this laboratory. No effort is made to cover all of the changes occurring but rather only a few which illustrate the problems or limit the practical application of the process. 

Holm, N. W., Jarrett, R. D., Evaluation of Dosimetry Procedures Applicable for Use in Food Irradiation, Radiation Preservation of Foods, p. 361, National Academy of Sciences, National Research Council, 1965. 

Another basic question is what type of facility would be most applicable —i.e., is a fixed or a mobile irradiator most applicable If a fixed facility is applicable, should it be an in-plant unit or a central facility to be used by several processors Seasonal availability of a product, near one location, is critical to the economics of radiation processing since typical capital costs for a moderate food irradiation plant may run anywhere between a quarter and two million dollars or more. Where there are relatively short harvest seasons, it would be economically advantageous to plan for irradiation of several products. This, however, requires a more flexible or versatile conveying system past the radiation source and generally less efficient use of the radiation. Thus, while a slight increase in capital cost may be required, the unit cost for processing would be less. 

The fission product and encapsulation plant (FPCE) to be built by Isochem, Inc.y in Washington state will produce fully encapsulated fission products for the commercial market. Among these, all of which are extractable from Hanford s plutonium process residues, is cesium-137, a 600-kv. gamma emitter of interest to the process irradiation industry. Isochem will offer cesium in large production quantities and low cost to irradiators of foods, woods, chemicals, etc. Its 30-year half-life promises economies in source array replenishment to compensate for decay. Cesium thus becomes an economic contender for current and planned irradiation applications. 

Although a relatively new commercial process, food irradiation has been studied more thoroughly than any other food technology. More than 40 years of research have shown conclusively that there are no adverse effects from the consumption of irradiated food. In fact for many foods, preservation by irradiation has proved to be by far the best method. Table 4.4 summarises the general applications of food irradiation technology. 

Cobalt exists in valence states from 0 to 5, with the most stable (4-2 and - -3) being most common. While there is only one stable isotope of cobalt, there are a number of unstable isotopes. Two of these, cobalt-60 and cobalt-57, are in use commercially. Cobalt-60 is used for cancer treatment and for food irradiation. Cobalt-57 has research applications. 

Table 1. Doses recommended for possible applications of food irradiation.

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