Development of bioplastic blown films to be used as a packaging for dried banana

Abstract

This research aimed to study effects of poly(butylene adipate-co-terephthalate) (PBAT) contents on properties of polylactic acid / poly(hydroxybutyrate-co-hydroxyvalerate) / poly (butylene adipate-co-terephthalate) (PLA/PHBV/PBAT) blends to be used as a packaging for solar-dried bananas. The blend of PLA and PHBV (PLA/PHBV) was fixed at weight ratio of 80/20 while the PBAT content was varied from 0-30 wt%. The films were prepared by melt compounding and blown film extrusion. It was found that the addition of PBAT decreased barrier properties of PLA/PHBV film. Gas barrier which is oxygen transmission rate (OTR) and water vapor transmission rate (WVTR) increased with increasing of PBAT content. The barrier properties of all blends were shown the acceptable values for dried banana storage. It was found that the blend with 20% of PBAT content show high flexibility. Meanwhile, morphology and thermal properties of films were also studied. Hence, PLA/PHBV with 20% PBAT (PB2) was selected to pack dried banana for 4 months at room temperature. Color change, moisture content, water activity and texture of dried banana during storage time were determined. The dried banana packed in commercial film was tested as control. The results show that the color change of dried banana in both commercial and bioplastic film show similar result. However, at the same storage time, the dried banana in PB2 film had lower moisture content and water activity than that in commercial film resulting in higher hardness value. Additionally, no fragmentation was visually observed in PB2 film during 6 months of soil burial test because the temperature, moisture content and pH of soil were not controlled in the suitable condition.