Functional films based on mechanoactivated starch with prolonged release of preservative

Abstract

Use of active edible films containing an antimicrobial agent - a new method of extending the shelf life of food products. Ensuring the controlled release of the preservative from the film is an urgent task. This work aims to introduce a new environmentally friendly process for the production of antifungal starch films with a prolonged release of a preservative using mechanoactivation in a rotor-stator device (RSD). Active films based on mechanoactivated starch hydrogels containing 0–5.0% (w/w) benzoic acid as a preservative and chitosan as a solubilizing additive (St-BA-Ch), as well as films containing sodium benzoate (St-SB) for comparison, were obtained by the casting method. Films were characterized using optical and atomic force microscopy, X-ray diffraction and tensile and moisture permeability testing data. It was found that benzoic acid is present in the St-BА-Ch-films in the form of submicron particles. St-BА-Ch films showed greater tensile strength and a lower release rate of the preservative into model media compared to St-SB films. It is established that mechanical activation of casting hydrogels in RSD allows increasing the strength films by an average of 2 times, as well as reducing the release rate of the preservative and the vapor permeability of the films. The antifungal activity of the films was confirmed using Aspergillus niger. The developed active St-BА-Ch film can be recommended for use in the food industry to extend the shelf life of food products.