Assessment of the enhancement potential of salicylic acid on physicochemical, mechanical, barrier, and biodegradability features of potato starch films

Abstract

Filmogenic suspensions based on starch (S) and salicylic acid/starch (SA-S) were prepared and used to produce casted films (TPS and SA-TPS). An extensive characterization was conducted on both suspensions and casted films to assess their properties. Results evidenced that after storage for 120 days at 4 ◦C and 25 ◦C, the mold and yeast counts were significantly lower in the SA-S than in the S suspensions. Moreover, SA-S had a much lower initial viscosity than S. In reference to the films produced, salicylic acid caused a significant increase in film crystallinity, as well as a 2.3-fold increase in stress at break and a 3.8-fold increase in Young’s modulus over the control films. Additionally, compared to TPS, the SA-TPS films exhibited a 46% decrease in water vapor permeability. All films showed a high biodegradation extent (≥85%) upon 75 days of home composting. These findings suggest that the salicylic acid addition at low concentrations (2 mM) can be a cost-effective approach for the development of highly stable starch filmogenic suspensions and also biobased films with distinguishing properties.