Active Food Packaging Coatings Based on Hybrid Electrospun Gliadin Nanofibers Containing Ferulic Acid/Hydroxypropyl-Beta-Cyclodextrin Inclusion Complexes

Abstract

In this work, hybrid gliadin electrospun fibers containing inclusion complexes of ferulic acid (FA) with hydroxypropyl-beta-cyclodextrins (FA/HP-β-CD-IC) were prepared as a strategy to increase the stability and solubility of the antioxidant FA. Inclusion complex formation between FA and HP-β-CD was confirmed by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC), and X-ray diffraction (XRD). After adjusting the electrospinning conditions, beaded-free fibers of gliadin incorporating FA/HP-β-CD-IC with average fiber diameters ranging from 269.91 ± 73.53 to 271.68 ± 72.76 nm were obtained. Control gliadin fibers containing free FA were also produced for comparison purposes. The incorporation of FA within the cyclodextrin molecules resulted in increased thermal stability of the antioxidant compound. Moreover, formation of the inclusion complexes also enhanced the FA photostability, as after exposing the electrospun fibers to UV light during 60 min, photodegradation of the compound was reduced in more than 30%. Moreover, a slower degradation rate was also observed when compared to the fibers containing the free FA. Results from the release into two food simulants (ethanol 10% and acetic acid 3%) and PBS also demonstrated that the formation of the inclusion complexes successfully resulted in improved solubility, as reflected from the faster and greater release of the compounds in the three assayed media. Moreover, in both types of hybrid fibers, the antioxidant capacity of FA was kept, thus confirming the suitability of electrospinning for the encapsulation of sensitive compounds, giving raise to nanostructures with potential as active packaging structures or delivery systems of use in pharmaceutical or biomedical applications.

The Relationships between Process Parameters and Polymeric Nanofibers Fabricated Using a Modified Coaxial Electrospinning

“…But on the other hand, the conversion is a very complicated process with many uncertain and changeable factors, involving several disciplines such as electrostatic dynamics, hydrodynamics, and polymeric rheology [12,13,14,15,16]. Thus, it is not strange that although numerous publications have reported the potential applications of electrospun nanofibers in a wide variety of fields, such as energy [17,18,19], environment [20,21,22,23], medicine [24,25,26,27], food engineering [28,29,30] and tissue engineering [31,32,33], no uniform theories about this process have been put forward. Often, a mathematical model that is built on a certain working fluid fails to predict another type of working fluid.…”

Molecular Functionality of Plant Proteins from Low- to High-Solid Systems with Ligand and Co-Solute

“…Similarly, an initial burst release was observed in electrospun gliadin nanofibers incorporating ferulic acid and hyroxypropyl-β-cyclodextrin in the formation of active food packaging coatings. Interaction between hydroxypropyl-β-cyclodextrin and ferulic acid blocked the phenyl ring of the latter to provide required stability, via hydrophobic interaction, within the prolamin matrix leading to optimum release of the hydroxycinnamic acid in food applications [148]. Finally, a release study on the thymol/γ-cyclodextrin complex encapsulated in zein nanofibrous web showed an increase in the amount of thymol release at temperatures 37 • C to 75 • C due to weakened hydrogen bonds, increase in the mobility of polymer chains and an increase in the kinetic energy of thymol diffusion that served well in antimicrobial food preservation [165].…”

Food Packaging Based on Nanomaterials

“…Specifically, five research papers and one review paper are included in the special issue “Food Packaging based on Nanomaterials”. The manuscripts by Sharif et al [3] and Bugatti et al [4], both make use of the electrospinning technique to generate active packaging coatings aimed at improving food quality and safety. Electrospinning has emerged as a very promising tool to generate nanomaterials for a broad number of applications, highlighting their potential in the biomedical area (given the ability of the technique to generate structures that simulate cell tissues), but which has also proven to be a useful and versatile technique for various food applications [5,6,7].…”

“…An additional advantage of the technique is that active substances may be incorporated within these ultrathin structures to give rise to packaging coatings with functional properties. Specifically, the manuscript of Sharif et al [3] describes the development of gliadin-based structures containing ferulic acid to generate antioxidant packaging structures. As a strategy to improve the stability of this antioxidant molecule, ferulic acid was previously incorporated within cyclodextrins to generate inclusion complexes that were subsequently electrospun using zein as the carrier biopolymer [3].…”