Irradiated spices

The objective of irradiation of food with y-rays is elimination of parasitizing insects, fungi, and bacteria to prevent premature spoiling of the food and the outbreak of diseases. In addition, retardation of aging and ripening of fruits and vegetables can be achieved. In the Federal Republic of Germany, irradiation of food with the exception of spices is not permissible. 

The doses applied for the widely used microbial decontamination by irradiation of spices, dried herbs, and dry vegetable seasonings (see Sec. 4.9) are much higher than the disinfestation doses. Thus radiation decontamination of these commodities is more than enough to kill also any insects eventually infesting them. 

A detailed monograph on irradiation of dry food ingredients has been published in 1988 [98], and an updated shorter summary appeared recently [99]. A Code of Good Irradiation Practice for the Control of Pathogens and Other Microflora in Spices, Herbs, and Other Vegetable Seasonings has been issued by the International Consultative Group on Food Irradiation [100]. 

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

France, Hungary, Mexico, The Netherlands, Norway, South Africa, and the United States, and global production of irradiated spices has increased from about 5000 tons in 1990 to over 60,000 tons in 1997. In the United States alone, over 30,000 tons of spices, herbs, and dry vegetable seasonings were irradiated in 1997, as compared to only 4500 tons in 1993 [101]. In 1999, about 95 million pounds of these products were irradiated accounting for about 10% of their total consumption [102]. 

One of the standardized methods, electron spin resonance (ESR) technique, permits identification of food that contains a hard, dry matrix, e.g., bone. When food containing bone is irradiated, free radicals are produced and trapped in the crystal lattice of the bone, which can be detected by ESR spectroscopy [137]. Thermoluminescence of contaminating minerals for detection of radiation treatment of, e.g., spices and dried fruits can be successfully applied [138, 139]. Another standardized method that has been developed for identification of irradiated fat-containing foods is the mass-spectrometric detection of radiation-induced 2-alkylcyclobutanones after gas-chromatographic separation [140]. The... 

The ICGFI [149] estimates that irradiation cost range from 10 to 15 per tonne for a low-dose application (e.g., inhibition of sprouting of potatoes or onions), and 100 to 250 per tonne for a high-dose application (e.g., to ensure hygienic quality of spices). These unit costs are considered to be competitive with alternative treatments. 

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]. 

Early research with irradiated paprika (Beczner et al, 1973), white pepper, nutmeg and ginger (Tjaberg etal., 1972) concluded that the technique was not suitable for the detection of these spices since the free radicals formed were short lived and could not be distinguished from intrinsic free radicals already present in the non-irradiated samples. More recently, a radiation-induced stable EPR signal has been observed for up to three months in paprika, white mustard and chilli (Stachowicz et al1992). 

The EPR signal derived from irradiated cellulose has also been observed in paprika. However, it has been pointed out that the detection of the cellulose lines can be difficult or impossible in the presence of the manganese signal especially if the spices have a low cellulose content (Helle and Linke, 1992). 

The technique of EPR spectroscopy has proved to be a non-destructive technique with the potential for the quick and easy identification of a number of irradiated products. However considerable research is still required into products such as Crustacea, exotic fruits and various spices. There would also appear to be considerable potential in the identification of irradiation in a number of packaging materials providing additional identification which would reinforce the results of other techniques. This should help to reassure the consumer and ensure that the technique of food irradiation is not abused. 

Farag Zaied, S.E.A., Aziz, N.H. and Ali, A.M. (1996) Comparing effects of washing, thermal treatments and gamma irradiation on quality of spices. Nahrung 40(1), 32-36. 

EFFECT OF y-IRRADIATION IN VOLATILE OIL COMPOSITION Currently, y-irradiation is used for the decontamination of spices but its effect on essential oil composition is controversial and contradictory in cardamom (Ljubica, 1983 Klaus and Wilhelm, 1990 Maija et al, 1990). 

Klaus, W. and Wilhelm, G. (1990) Chemo metric evaluation of GC/MS profiles for the detection of y-irradiation of spices exemplified with nutmeg. Deutsch Lebensmittel-Rundsuchung 86, 344-348. 

Variyar, P.S., Bandyopadhyay, C. and Thomas, P. (1 998) Effect of y-irradiation on the volatile oil constituents of some Indian spices. Food Research International 31 (2), 105-109. 

Frage, S.E.A. and Abozeid, M. (1997) Degradation of the natural mutagenic compound safrole in spices by cooking and irradiation. Nahrung 41,359-361. 

Radiation also is an important tool in the medical treatment of cancer. However, what may be one of its most important applications, extending the storage life of foods, has been seriously delayed by public concern, in spite of extensive tests showing that irradiated foods meet all international safety standards. Currently, the United States irradiates spices for the main purpose of bug removal. 

Radiation sterilization produces foods that are stable at room temperature and requires a dose of 20 to 70 kGy. At lower doses, longer shelf life may be obtained, especially with perishable foods such as fruits, fish, and shellfish. The destruction of Salmonella in poultry is an application for radiation treatment. This requires doses of 1 to 10 kGy. Radiation disinfestation of spices and cereals may replace chemical fumigants, which have come under increasing scrutiny in recent years. Dose levels of 8 to 30 kGy would be required. Other possible applications of irradiation processing are inhibition of sprouting in potatoes and onions and delaying of the ripening of tropical fruits. 

Radiation chemical studies of antioxidants and their products of radiolysis should be developed as markers for testing the irradiated foods and spices, which are known to contain many different types of... 

It may be necessary to exclude certain undesirable contaminants from starting materials, such as pseudomonads from bulk aluminium hydroxide gel, or to include some form of pre-treatment to reduce their bioburdens by irradiation, such as for ispaghula husk and spices. For biotechnology-derived drugs produced in human or animal tissue culture, considerable efforts are made to exclude cell lines contaminated with latent host viruses. Official guidelines to limit the risk of prion contamination in medicines require bovine-derived ingredients to be obtained from sources where bovine spongiform encephalopathy (BSE) is not endemic. 

A last European protocol uses thermoluminescence (TL) irradiation results in positive ions and free electrons, which can be relatively stable in solid and dry foodstuffs. When the food is fastly heated, the recombination of ions and electrons leads to light emission (luminescence). It was later pointed out that the seat of the phenomenon is not in the vegetable material itself but in contaminating mineral particles adhering to the products. On this basis, an European protocol (EN 1788) has been approved for herbs, spices and shrimps. 

Baraldi, D. (1996) Irradiation in the preservation of spices, herbs and condiments. Infor-matore Fitopatologico 46, 23-27. 

Currently in the United States, some spices such as black peppers, ground paprika and some blend of spices are irradiated for the wholesale market and for some speciality foods such as pastrami. The purpose is decontamination at a dose range of 10 kGy and higher. These spices and seasonings have been irradiated in the past few years at commercial irradiation plants in New Jersey, California and elsewhere. The quantities irradiated in the past two years are estimated to be around 1,000 to 2,000 metric tons per year. 

If you eat processed food, you have probably eaten ingredients exposed to radioactive rays. In the United States, up to 10 percent of herbs and spices are irradiated to control mold, zapped w ith X rays at a dose equal to 60 million chest X rays. Although food irradiation has been used in one way or another for more than 40 years, it faces an uncertain future in this country. 

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