Biodegradable packaging films based on starch and cabbage pomace: mechanical properties and antimicrobial activity

Biodegradable packaging films based on potato and corn starch and cabbage pomace were developed, containing natural biologically active compounds, particularly glucosinolates and their hydrolysis products, isothiocyanates and indoles. The effect of starch, glycerol, and lactic acid on tensile mechanical properties and antimicrobial activity of the obtained films were examined. Antimicrobial properties were assessed in a model storage test using bread. Potato starch films were characterized by a higher Young's modulus and higher tensile strength than those made from corn starch. Increasing the glycerol content from 1 to 3 phr resulted in a decrease in Young’s modulus and tensile strength, while simultaneously increasing the elongation at break. The strongest anti-mold effect was achieved for films containing a cabbage biopreparation and lactic acid, for which no mold growth was observed up to approximately 45 days of storage. The obtained films were biodegradable in natural environmental conditions, which indicates their potential use in the production of biodegradable packaging materials for short-term use.