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Stability of aseptically packaged food as a function of oxidation initiated by a polymer contact surface

In this study, low density polyethylene (LDPE) and polyethylene terephalate (PETE) resin beads were ground to a coarse powder and exposed to sterilization treatments applied to the food contact surface of packaging materials used in aseptically processed and packaged food. Electron paranlagnetic resonance (EPR) analyzed free radical (-CH2CHCH=CHCHz-) production on the surface of LDPE exposed to heat (107°C) and treatments of heat (107°C) + 30% hydrogen peroxide solution (H20 2). As the temperature was raised from 100° to 200°C, peak intensity of carbon radicals produced gradually increased. The sensitivity of EPR prevented detection of free radicals on LDPE, exposed to H20 2 treatment, due to residual peroxide and H20 condensation on the surface of LDPE. D-limonene was placed in 12ml sealed glass vials containing a sodium citrate buffer solution (pH=3.7), under atmospheric O₂ (21%) conditions. Oxidation of d-limonene, placed in intimate contact with untreated, HzOz treated, and ultraviolet (VV) light (650mW/cm2) treated LDPE for 15 weeks, was measured to determine the capacity of an oxidized polymer to initiate autoxidation. The oxidation of d-limonene in vials containing no polymer was also measured. Production of carvone and carveol were used as an index for oxidation. No polymer and UV treated samples showed significantly (P<0.05) higher levels of calVone and calVeol than samples containing untreated and HzOz treated LDPE. Samples containing no polymer oxidized d-limonene at the highest rate, but not significantly faster than solutions containing UV treated LDPE. Accumulation of carvone and carveol was zero order. / Ph. D.

Identiferoai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/37988
Date06 June 2008
CreatorsBerends, Corey L.
ContributorsFood Science and Technology, Marcy, Joseph E., Hackney, Cameron Raj, Eigel, William N. III, Johnson, Janet M., Barbeau, William E.
PublisherVirginia Tech
Source SetsVirginia Tech Theses and Dissertation
LanguageEnglish
Detected LanguageEnglish
TypeDissertation, Text
Formatxiii, 133 leaves, BTD, application/pdf, application/pdf
RightsIn Copyright, http://rightsstatements.org/vocab/InC/1.0/
RelationOCLC# 35832117, LD5655.V856_1996.B474.pdf

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