Mechanical, Barrier, and Biodegradation Properties of Apple Peel Pectin–Porang Starch Films Containing Chitosan and Peppermint Essential Oil

ABSTRACT Bioplastic films based on apple pectin were developed by incorporating porang ( Amorphophallus muelleri Blume) starch, chitosan, glycerol, and peppermint essential oil, and their physicochemical, mechanical, barrier, optical, and biodegradation properties were evaluated. Increasing porang starch content was associated with thicker films with reduced moisture content, solubility, initial water uptake, and water vapor transmission rate, together with increased stiffness accompanied by lower elongation. Initial water uptake tended to decrease, but the effect was not statistically significant. Chitosan significantly affected water vapor transmission rate without significantly affecting the measured mechanical properties, water‐related properties, or color. The initial addition of peppermint essential oil was associated with increased film flexibility; however, residual essential oil content after drying was not quantified. Soil‐burial tests showed time‐dependent changes in measured film mass over 14 days, with an initial mass increase followed by a general decrease during burial. These results demonstrate a tunable balance among stiffness, flexibility, barrier performance, and degradation‐related behavior, highlighting the potential of apple peel pectin‐based composite films for sustainable food‐packaging applications.