Transport Coefficients of Eucalyptol through Various Polymeric Films

Abstract

This study presents the determination of the transport properties of eucalyptol, which is a key aroma compound in fresh tropical herbs through different polymeric packaging materials. Packaging films used in this study were polyethylene, polypropylene, Nylon, polyethylene terephthalate and polylactide (PLA1 and PLA2). Test films were immersed in the 1000ppm of aroma compound and stored in amber vials. The concentrations of aroma compounds extracted from films were determined using gas chromatography. Diffusion, solubility, permeability and partition coefficients were calculated from sorption kinetics. Results show that the diffusion and solubility coefficients of eucalyptol were lowest in PLA1 and highest in polyethylene. Solubility coefficients were associated with partition coefficients as well as solubility parameters and contact angle values. Primary factor determining solubility was affinity between the aroma compounds and the polymeric films. Transport coefficients of eucalyptol in the vapor phase followed the same trends as in the liquid phase with about 3-fold greater. Understanding interaction phenomenon between the key aroma compound and major packaging films may contribute to improvements in film selection and the design of food packaging applications. Finding from this research contributes toward future development of the high-aroma barrier materials. M t /M∞ M t /M∞ M t /M∞ a Solubility coefficients obtained from immersion study. 21

Preliminary quantification of the permeability, solubility and diffusion coefficients of major aroma compounds present in herbs through various plastic packaging materials

“…LDPE had the highest P for most of the tested aroma compounds; except for eucalyptol where PLA show the highest P . This was inconsistent with the results from previous study showing that the P of eucalyptol was highest in PE (1.98 × 10 −19 m 2 s −1 ) comparing to PLA (9.80 × 10 −22 m 2 s −1 ) from the sorption method in liquid phase . This was probably due to the different method and model used.…”

“…However, limited information is available on the interaction between key aroma compounds present in herbs and major polymeric films used for packages. To the authors' knowledge, the permeability of aroma compounds in herbs through various plastic films was only reported for eucalyptol but using different methods and model . In this study, we report the mass transfer measurements of key aroma compounds in herbs such as eucalyptol, estragole, linalool and citral through major packaging films using a quasi‐isostatic system, and we also report preliminary P , D and S from experimental concentration vs. time data.…”

Effects of packaging materials on the aroma stability of Thai ‘tom yam’ seasoning powder as determined by descriptive sensory analysis and gas chromatography-mass spectrometry

“…The results indicated that the three packaging materials provided similar protection against the aroma loss of Thai 'tom yam' seasoning powder at 38 ∘ C. These materials were shown to possess good aroma barrier properties according to the results from our previous sorption studies, which reported that Nylon, PET and PLA were good barriers to eucalyptol. 16 The results also corresponded to the previous study showing that PET-based films provided good protection against aroma loss in Australian native herbs containing lemon myrtle, anise myrtle and Tasmanian pepper leaf. 13 While the results suggested that these polymeric materials can be used as an aroma barrier, there are several other factors to consider when selecting materials for packaging applications.…”

Development and evaluation of organic vapour permeation system for packaging applications

“…The highest permeability of all tested compounds except for eucalyptol were observed in low‐density polyethylene (LDPE), while lowest in polyethylene terephthalate (PET) and metalized PET (MPET) . Considering that eucalyptol, polylactic acid (PLA) had the highest permeability compared with LDPE, this result was contradictory to previous findings . The pressure‐dependency of permeability at temperature below critical temperature was reported …”

“…7 Considering that eucalyptol, polylactic acid (PLA) had the highest permeability compared with LDPE, this result was contradictory to previous findings. 8 The pressure-dependency of permeability at temperature below critical temperature was reported. 9 The permeation curves were found to be very similar with results of Apostolopoulos and Winters, 10 indicating that a high concentration gradient of organic vapours increased the rate of diffusion and had much shorter lag time, thereby allowing the system to reach equilibrium even faster.…”