Characterisation of flavour compounds formed by γ-irradiation of polypropylene

• Published in: Polymer degradation and stability 2009-05, Vol.94 (5), p.757-769
• Main Authors: Tyapkova, Oxana, Czerny, Michael, Buettner, Andrea
• Format: Article
• Language: English
• Subjects: Applied sciences; Aroma extract dilution analysis (AEDA); Exact sciences and technology; Gas chromatography–olfactometry (GC–O); Physical properties; Polymer industry, paints, wood; Polypropylene (PP); Properties and testing; Radiation influence; Radiolysis products; Technology of polymers; γ-Irradiation
• ISSN: 0141-3910; 1873-2321
• DOI: 10.1016/j.polymdegradstab.2009.02.006

Sterilisation of plastic packaging materials for food, pharmaceutical or cosmetic products with 60Co γ-irradiation in the presence of oxygen can result in the formation of volatile substances. These may subsequently induce off-odours in these materials that might be regarded as negative by the consumers. Trace volatiles and odorous substances of polypropylene, irradiated with 60Co γ rays at 10 and 20 kGy, respectively, were collected and analysed by gas chromatography–olfactometry (GC–O), GC–MS and GC–GC–MS. The methodology was successfully applied for identification of 29 characteristic odorants in a non-irradiated control sample and 38 odorants in γ-irradiated polypropylene samples. Selected odour-active compounds were quantified using GC–GC–MS in combination with stable isotope dilution assays. The quantitative data mirrors the compositional changes in volatile odorous substances from polypropylene during treatment with ionising γ rays in a 60Co-irradiation plant.