A new method to measure aroma transport through polymeric films is introduced. This recirculating constant-volume method minimizes localized concentration gradients, allows for the evaluation of high barrier films, and provides a humiditygeneration scheme which is simple, accurate, and easy to implement. Vinylidene chloride copolymer co-VDC, and ethylene vinyl alcohol copolymer, EVOH, were tested under identical conditions to evaluate the efficacy of the methodology. Additionally, edible, hydrophilic whey protein isolate (WPI) films were tested at identical temperature and permeant concentration levels with three different levels of relative humidity. The permeability coefficient measured for d-limonene in co-VDC (55℃) was 18,000 MZU(±5000) 1 MZU=10{sup}-20 kg-m/(m{sup}2-s-Pa), while the measured value of d-limonene permeability coefficient in EVOH (55℃, 50 RH) was 0.9 MZU (±0.3). These values are within the range of reported literature values for co-VDC and EVOH. Anexponential relationship between d-limonene permeability and relative humidity in the WPJ films (40℃) was suggested, with the permeability coefficients increasing from 1.2 to 3.2 to8.8 MZU as the relative humidity increased from 40 to 60 to 80 RH,respectively. The preliminary data for WPI films indicated they were comparable to EVOH, the industry standard for hydrophilic barrier films.
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