Preparation and Characterization of Electrospun Food Biopackaging Films of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) Derived From Fruit Pulp Biowaste

In the present study, circular economy based and potentiall y low-cost poly(3-hydroxybutyrate- co -3-hydroxyvalerate) (PHBV) was produced by mixed microbia l cultures derived from fruit pulp, an industrial by-product of the juice industry. Three different chemical routes, namely non-extraction, extrac tion with sodium hypochlorite (NaClO), and extraction with chloroform, in combination wi th filtering and centrifugation, were explored to purify the biopolymer and find the most optim al solution for its processing via electrospinning. The resultant ultrathin fiber mats of the d ifferent extracted PHBV materials were thermally post-processed at different temperatures in order to obtain continuous films adequate for food packagi ng applications. The resultant films were characterized in terms of morphology, c rystallinity as well as thermal, mechanical, and barrier properties. The results s howed that extraction with both chloroform and NaClO with a post-treatment of filtering and centrifugation of the PHBV-containing biomass were necessary refining steps to al low its processing by electrospinning. In particular, the PHBV extracted with ch loroform presented the highest degree of purity, resulting in more transparent films with lo wer wettability and higher flexibility. The here-formulated electrospun films made of b iomass derived from biowaste exhibit great potential as interlayers or coatings for food biopackaging applications