PHBV/PCL blend films with active compounds to prolong the shelf life of meat

Active films based on PHBV/PCL (PP) blends in a 1:1 ratio were obtained by melt blending and compression moulding, with and without 6 % (w/w) ferulic acid (FA) or rice straw extract (RSE), obtained by subcritical water extraction at 180 °C. These films (PP, PPFA and PPRSE) were characterised as to their functional, structural and heat-sealing properties, and their ability to preserve pork meat. Structural analysis revealed the immiscibility of the polymers in the mixture, although the active compounds improved interfacial adhesion. The microstructure of the PHBV and PCL phases was affected to a different extent by the active compounds. These did not modify the thermal stability of PCL, but RSE reduced the thermal stability of PHBV. The active compounds promoted UV-light blocking in the films, slightly modified their mechanical properties, and reduced the heat seal strength, without significantly affecting oxygen permeability. RSE slightly promoted water vapour permeability. Blend films with both active compounds extended the shelf life of cold-stored pork by up to 5 days compared to films without active compounds, limiting oxidative reactions and inhibiting bacterial growth. • Heat-sealable, active films from PHBV/PCL (1:1) and ferulic acid or RSE were obtained. • Active components affect differently the microstructure of both polymer phases. • Mechanical performance of the materials was slightly affected by active compounds. • Active compounds did not affect oxygen permeability, but RSE enhances that of water vapour. • Shelf life of chilled pork meat was extended by 5 days when bagged in active films.