Development of Active Barrier Multilayer Films Based on Electrospun Antimicrobial Hot-Tack Food Waste Derived Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and Cellulose Nanocrystal Interlayers

Abstract

Active multilayer films based on polyhydroxyalkanoates (PHAs) with and without high barrier coatings of cellulose nanocrystals (CNCs) were herein successfully developed. To this end, an electrospun antimicrobial hot-tack layer made of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) derived from cheese whey, a by-product from the dairy industry, was deposited on a previously manufactured blown film of commercial food contact PHA-based resin. A hybrid combination of oregano essential oil (OEO) and zinc oxide nanoparticles (ZnONPs) were incorporated during the electrospinning process into the PHBV nanofibers at 2.5 and 2.25 wt%, respectively, in order to provide antimicrobial properties. A barrier CNC coating was also applied by casting from an aqueous solution of nanocellulose at 2 wt% using a rod at 1m/min. The whole multilayer structure was thereafter assembled in a pilot roll-to-roll laminating system, where the blown PHA-based film was located as the outer layers while the electrospun antimicrobial hot-tack PHBV layer and the barrier CNC coating were placed as interlayers. The resultant multilayer films, having a final thickness in the 130–150 µm range, were characterized to ascertain their potential in biodegradable food packaging. The multilayers showed contact transparency, interlayer adhesion, improved barrier to water and limonene vapors, and intermediate mechanical performance. Moreover, the films presented high antimicrobial and antioxidant activities in both open and closed systems for up to 15 days. Finally, the food safety of the multilayers was assessed by migration and cytotoxicity tests, demonstrating that the films are safe to use in both alcoholic and acid food simulants and they are also not cytotoxic for Caco-2 cells.

High-Oxygen-Barrier Multilayer Films Based on Polyhydroxyalkanoates and Cellulose Nanocrystals

“…in our lab also showed no difference in mechanical properties between multilayers with a CNC coating and those without the CNC layer [49].…”

“…Previous studies in our laboratory developed multilayers for their use in both rigid and flexible packaging with antimicrobial and vapor barrier properties, in which electrospun PHA fibers with active substances and CNC coatings were used as intermediate layers to provide these properties [41,49]. Following this concept, the present study focuses on the development of new multilayer designs for use as a high-oxygen-barrier film.…”

Nano-Enable Materials Promoting Sustainability and Resilience in Modern Agriculture

“…The resultant multilayer films were characterized to ascertain their potential in biodegradable food packaging. The films presented high antimicrobial and antioxidant activities and improved the barrier to water and limonene vapors [ 159 ].…”

Effect of Different Essential Oils on the Properties of Edible Coatings Based on Yam (Dioscorea rotundata L.) Starch and Its Application in Strawberry (Fragaria vesca L.) Preservation

“…As expected, the dispersed phase of essential oil causes the internal homogeneity of the material to decrease as a consequence of higher diffraction of the light 33. From a food preservation point of view, reduced transparency in food packaging materials can also be a positive feature because light scattering can help prevent photo-oxidation and degradation of organic compounds in food products [42]. Different superscript letters within the same column indicate significant differences among formulations (p < 0.05).…”