Irradiation treatment

MetaHoelement complexes may be useful for the post-irradiation treatment of radiation injury, based on the observation that several of these compounds accelerate recovery of, among other things, lympho/hemopoiesis. Preirradiation Mn2(0)(DIPS)g increases the survival of y-irradiated mice (103). Treatment of mice that have been exposed to an LD q q dose of y-rays plus Mn2(0)(DIPS)g either 1 or 3 h after irradiation also increases survival, which supports the hypothesis that this compound is an effective radiorecovery agent (105). Again, this increase in survival may result from the resynthesis of radiation-depleted Mn-dependent enzymes that facHitate the recovery of immunocompetence and tissue repair, as reported for Cu(II)2(DIPS)4. 

Table IV shows the data on rigidity changes of the end-sealing compounds at two dose levels. Rigidity was determined by torsional braid analysis (5). These data indicate that the blend of cured and uncured isobutylene-isoprene copolymer was softened most by the irradiation treatment, the blend of polychloroprene and butadiene-styrene copolymer softened the least, and the blend of polychloroprene and the uncured isobutylene-isoprene copolymer was intermediate. Increasing the irradiation dose from 3-4 Mrad to 6-7.5 Mrad decreased the rigidity of the three end-sealing compounds. The irradiation temperature did not significantly influence rigidity.

Following the same procedures described in the above-mentioned study, additional extractive data were obtained for the epoxy phenolic enamel that was irradiated at 4.7-7.1 Mrad at 25 and — 30 °C in the presence of distilled water, 3% acetic acid, and n-heptane. The changes in the amount of extractives resulting from the irradiation treatment are shown in Table IX. In the case of the water and acetic acid extractives, there was no change in either the chloroform-soluble fractions or the chloroform-insoluble fractions. In the case of the n-heptane extractives, the amount of extractives decreased when the irradiation temperature was reduced from +25 to — 30°C. Infrared spectra of the chloroform-soluble residues from the water and acetic acid extractives of the unirradiated and irradiated enamel were identical to the chloroform-soluble residues from the solvent blanks. In other words, the epoxy phenolic... 

Bond strength data for four multilayered materials is shown in Table V. In each case the data is for the bond between the food-contacting layer and its adjacent layer. In Pouch 1, it is the bond between ethylene-butene copolymer and aluminum foil in Pouch 2 between ethylene-butene copolymer—polyisobutylene blend and aluminum foil in Pouch 3 between ethylene-butene copolymer and polyiminocaproyl and in Pouch 4 between ethylene-butene copolymer and poly(ethylene terephthalate). Bond strength increased in the four multilayered materials after the irradiation treatment. 

Boag, T.S., G.I. Johnson, M. Izard, C. Murray, and K.C. Fitzsimmons. 1990. Physiological responses of mangoes cv. Kensington Pride to gamma irradiation treatment as affected by fruit maturity and ripeness. Ann. Appl. Biol. 116 177-187. 

Dajka, K Takacs, E Solpan, D Wojnarovits, L Guven, O. High-energy irradiation treatment of aqueous solutions of C.l. Reactive Black 5 azo dye pulse radiolysis experiments. Radiation Physics and Chemistry, 2003 67, 535-538. 

An irradiation dose of 1.0 kGy treatment decreased mesophilic bacteria in Mexican salads (Erickson, 2008). However, irradiation can cause changes in pectin structure leading to texture loss and hence shelf life. Also, viruses seem to be relatively resistant to irradiation treatment and relative to vegetative cells, suggesting that doses delivered to inactive... 

Bari, M. L., Nakauma, M., Todoriki, S., Juneja, V. K., Isshiki, K., and Kawamoto, S. (2005). Effectiveness of irradiation treatments in inactivating Listeria monocytogenes on fresh vegetables at refrigeration temperature. J. Food Prot. 68, 318-323. 

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... 

Radiation decontamination of meat was first commercially implemented in Brittany, France, when e-beam irradiation treatment was established for frozen slabs of mechanically separated chicken meat [57,58]. 

Petitions by the National Fisheries Institute for approval of irradiation treatment to control food-borne pathogens in raw or processed crustaceans are pending at the regulatory authorities in the United States [70]. 

There is no evidence or reason to expect that irradiation produces more virulent pathogens among those that survive irradiation treatment [123,124]. 

Comments on the DG SANCO Consultation of Consumer Organizations, Industry Concerned and Other Interested Parties on the Strategy for Completion of the Positive List of Food and Food Ingredients to be Authorised for Irradiation Treatment, Annex of Directive 1999/3/EC, SANCO/4175/2000-rev.l, European Commission, Health and Consumer Protection Directorate-General, Directorate D - Food Safety Production and Distribution Chain, Brussels, 2000. Ehlermann, D.A.E. Radiat. Phys. Chem. 2002, 63, Til. 

The destruction of color centers (1,3) by heating can result in bleaching or fading. Examples are brown or blue topaz, red tourmaline, smoky quartz, and some yellow sapphire. In other instances there may be a color change as when amethyst turns into yellow citrine, or when the heating of a brown topaz reveals the presence of a previously hidden Cr-derived color in a pinked topaz. These changes can usually be reversed by an irradiation treatment. 

The shape of the radiation-induced signal was similar in different components of the exoskeleton of Norway lobster but the intensity of the peak varied (Stewart etal., 1993a). Consequently, the part of the cuticle used for EPR analysis will not affect identification of irradiation treatment but could influence the estimation of dose in samples of unknown processing history. 

Anon. (1992). Coordinated Research Programme on Analytical Detection Methods for Irradiation Treatment of Foods (ADMIT). Second Research Co-ordination Meeting, Hungary, 15-19 June, IAEA, Vienna, 15. 

Scotter, S.L., Holley, P. and Wood, R (1990). Co-operative trial of methods of analysis to detect irradiation treatment of chicken samples. Int J. Food Sci. Technol. 25. 512. 

Table IV gives the analytical results obtained for all of the amino acids except cystine, cysteic acid, and tryptophan for the various irradiation treatments given in Table I as well as for the frozen nonirradiated control beef. Table V gives the assay data for cystine plus cysteine, by the colorimetric procedure, and cysteic acid. The assay data for tryptophan in Table V were determined by the fluorometric procedure.

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