Degradation of low density polyethylene during extrusion. III. Volatile compounds in extruded films creating off‐flavor

Abstract

ABSTRACT:This study was aimed at finding a correlation between the experienced off-flavor in packaged foods and the presence of specific degradation products in PE packaging films. The possibility to trap degradation products by chemical reactions with scavengers, that is, zeolites and maleic anhydride grafted LLDPE, were investigated. This trapping would prevent the degradation products from migrating to the polymer film surface and further into food in contact with the film. This work concludes that off-flavor in water packed in LDPE-films depends on extrusion temperature and the content of oxidation products in the polymer film. At lower extrusion temperatures, reactive additives to the LDPE material could control the release of off-flavor giving components. Adsorbents, such as zeolites, which are able to adsorb degradation products, are effective also at higher extrusion temperatures. The amount of oxidized degradation products in the films correlated well to the perceived off-flavor in the packed water. The presence of aldehydes and ketones have a clear impact on the off-flavor. The best correlation between off-flavor and oxidized components were found for C 7 -C 9 ketones, and aldehydes in the range of C 5 to C 8 . © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 847-858, 2005

Thermal and mechanical modification of LDPE in single‐screw extruder

“…As the drawback of such high‐temperature processing, however, some oxidized substances were found both in the smoke from extruded films3 and also in the films 4. The oxidized compounds lead to an “off‐flavor” that affects the taste of products in the food package 5, 6…”

Physico‐Mechanical Properties, Odor and VOC Emission of Bio‐Flour‐Filled Poly(propylene) Bio‐Composites with Different Volcanic Pozzolan Contents

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Improvements in single‐use bioreactor film material composition leads to robust and reliable Chinese hamster ovary cell performance

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