Abstract
A supercritical solvent impregnation (SSI) technique was employed to incorporate, by batch- and semicontinuous-modes, bioactive olive leaf extract (OLE) into a food-grade multilayer polyethylene terephthalate/polypropylene (PET/PP) film for active food packaging applications. The inclusion of OLE in the polymer surfaces significantly modified the colour properties of the film. A correlation of 87.06% between the CIELAB colour parameters and the amount of the OLE impregnated in the film was obtained which suggests that colour determination can be used as a rapid, non-destructive technique to estimate the OLE loading in the impregnated matrices. The UV barrier and water permeability properties of the films were not significantly modified by the incorporation of OLE. The migration of OLE into a 50% (v/v) ethanol food simulant demonstrated faster release of OLE from the PP surface than from the PET surface which may be due to the different interactions between OLE and each polymer.
Highlights
Given the perishable nature of fresh produce, packaging is an investment necessary for producers to protect and preserve products from post-harvest through to sales and distribution
Volatile compounds derived from essential oils and extracts with antibacterial and antioxidant capacities have been used because of their propensity to be released into the headspace of the packaging [6,7,8]
The inclusion of UV blockers into the package to absorb some wavelengths has been utilized in film formulations in order to increase the shelf-life of different products [14,39]
Summary
Given the perishable nature of fresh produce, packaging is an investment necessary for producers to protect and preserve products from post-harvest through to sales and distribution. Active packaging describes a system in which the materials actively participate in food preservation by different mechanisms, such as delaying lipid oxidation, inhibiting microbial growth, inhibiting absorption of moisture or vapour exchange, among others [4] This type of packaging is designed to incorporate active components into an inert polymer matrix to either absorb undesired compounds, such as gases or off-flavours, or to be released into the package headspace [5]. Supercritical CO2 (scCO2) has the dual ability to solubilise the active compound, with or without the addition of a co-solvent, and to act as a plasticizer of the polymer matrix by opening its chains and favouring the subsequent solute-matrix reaction [18,19] This technique takes advantage of the low temperatures required for the impregnation The present work aims to further characterise these films in terms of their barrier parameters, colour, water permeability and UV barrier properties, as well as study the mass transfer of OLE from the films under optimum impregnation conditions
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
