73D-16 |
Determination and application of GC/MS response factor for gamma-irradiated Ethylene Vinyl Alcohol |
J. HANNECART, G. Sadler, and E. A. Miller. National Center for Food Safety & Technology, Illinois Institute of Technology, 6502 S. Archer Rd., Summit-Argo, IL 60501 Irradiation improves the safety of food through its lethal effect on microorganisms. A food that is irradiated inside a sealed package would prevent re-contamination resulting from subsequent handling. However, irradiation of a packaging material may theoretically lead to the creation of undesirable radiolytic compounds. Our objective was to identify and quantify all compounds arising or increasing from ?-irradiation of ethylene vinyl alcohol (EVOH) up to 10 kGy of treatment. A method was developed that delimits organic compounds that are present above FDA's Threshold of Regulation (TOR) for EVOH, . 1 TOR is here defined as 7.18e-8 g of compound per 0.1 g of polymer and represents the contaminant load which would impart 0.5 ppb dietary concentration of a given radiolytic product. Standard solutions of organic compounds (alkanes, alcohols, carboxylic acids, ketones, aldehydes, aromatics) with carbon number ranging between 1 and 20 have been analyzed through a GC-MS system. Ground, irradiated EVOH samples were analyzed using an ATD-GC-MS system. Eluted volatiles of irradiated polymer were compared to the compounds extracted from the standard non-irradiated polymer. The compounds were further quantified using the standard solution of organic compounds listed above. This allowed us to determine the concentration of irradiation-induced molecules, which were present at a level of greater than 1 TOR. Our results showed that the level of the following compounds increased above the 1 TOR due to irradiation: acetic acid (from 36.3 to 62 TOR level), formic acid (from 0.14 to 2.3 TOR), acetone (0.5 to 2.7 TOR), butane (absence to 1.4 TOR), 2,4-diphenyl-4-methyl-2-(Z)-pentene (from 1 to 1.3 TOR), alpha-methylstyrene (from 0.3 to 1.2 TOR) and 1-methylethyl benzene (from 0.04 to 1 TOR). All compounds increasing with irradiation above one TOR were either Generally Recognized As Safe (GRAS) or present as part of the virgin EVOH background.
Session 73D, Food Packaging
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