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

Abstract

[EN] In the present study, circular economy based and potentially low-cost poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) was produced by mixed microbial cultures derived from fruit pulp, an industrial by-product of the juice industry. Three different chemical routes, namely non-extraction, extraction with sodium hypochlorite (NaClO), and extraction with chloroform, in combination with ¿ltering and centrifugation, were explored to purify the biopolymer and ¿nd the most optimal solution for its processing via electrospinning. The resultant ultrathin ¿ber mats of the different extracted PHBV materials were thermally post-processed at different temperatures in order to obtain continuous ¿lms adequate for food packaging applications. The resultant ¿lms were characterized in terms of morphology, crystallinity as well as thermal, mechanical, and barrier properties. The results showed that extraction with both chloroform and NaClO with a post-treatment of ¿ltering and centrifugation of the PHBV-containing biomass were necessary re¿ning steps to allow its processing by electrospinning. In particular, the PHBV extracted with chloroform presented the highest degree of purity, resulting in more transparent ¿lms with lower wettability and higher ¿exibility. The here-formulated electrospun ¿lms made of biomass derived from biowaste exhibit great potential as interlayers or coatings for food biopackaging applications.