By means of thermal desorption experiments, the partition equilibrium (part
ition coefficient, K) was analysed for six food aroma components (d-limonen
e, n-decane, ethyl caproate, phenylethanol, n-hexanol and hexanal) between
three sealable polymer films suitable for direct food contact (ultra-low de
nsity polyethylene, ULDPE; ionomer, ION; and polyester, PET) and four fatty
food simulants (ethanol 95%, EtOH: sunflower oil, Oil; n-heptane, HEP; and
iso-octane, OCT). The results showed that aroma scalping is highly depende
nt on the fatty food simulant utilized. Polar aroma components were more so
rbed into polymers in the presence of a non-polar fatty food simulant, and
vice versa. K values in the presence of Oil were always between those in Et
OH and in HEP or OCT. In general, PET was the packaging film which showed t
he lowest partition coefficient for non-polar components while ULDPE showed
the lowest partition for polar aromas. The partition equilibrium of mixed
d-limonene, ethyl caproate, and n-hexanol was also determined. The differen
ces in K values between isolated aromas and mixed aromas were small. In gen
eral, the most sorbed aroma showed increased partition by mixture while the
partition of the least sorbed was reduced.