Volatiles in Extrusion Coating LDPE That Determine Organoleptic Properties, 1998 Polymers, Laminations & Coatings Conference Proceedings

Over the last few decades the organoleptic performance of packaging materials for foodstuffs has become increasingly important. To be able to carry out efficient and reliable quality control and to improve the organoleptics of packaging materials, it is necessary to make these odour and taste properties measurable by determining the exact cause of the off-taste.

In this paper we focus on the organoleptics of extrusion coating LDPE for aseptic liquid packaging applications. By means of headspace GC-MS, RP-HPLC and a taste panel, the cause of off-taste in packed water was determined using samples of water in which film specimens had been incubated (“film samples”) and synthetic water samples. According to the panel the off-taste of film samples was similar to the off-taste of synthetic water samples containing aldehydes and ketones (1.5 ppb) together with acids (100-200 ppb). Apparently, the off-taste was due to a synergistic effect of these components, as no single threshold level quoted in the literature had been exceeded. On the basis of these results a concentration region was defined within which off-taste is to be expected. This means it is now possible to control the organoleptic quality of LDPE by means of GC analysis.