Studying the food bioactive pectin-based films structure and properties

Abstract

The purpose of the study is to establish the structure and properties of bioactive films based on pectin. The objects of study are films obtained on the basis of the structure-forming agent pectin with the addition of protein hydrolyzate as an active component. The microstructure of the produced films was determined using scanning electron microscopy; physicochemical properties (biodegradability, solubility, thickness, moisture content); bioactive properties (antioxidant capacity, ability to absorb DPPH radicals, content of polyphenols and flavonoids) spectrophotometrically. The addition of protein hydrolyzate to the composition of the pectin film changed its structural properties: a dense cellular network was formed, due to which the film became less susceptible to water and took longer to biodegrade in compost, and its thickness became smaller compared to the control. Moreover, both film samples completely turned into vermicompost after 2 weeks, which shows the high biodegradability of pectin films. The antioxidant properties of the films also improved: antiradical activity increased by 11 %, and antioxidant capacity by 49 % compared to the control sample. The introduction of protein hydrolyzate into the composition of a pectin film can solve a number of problems in the monocomponent composition of a pectin-based film, improve the structural characteristics and moisture resistance. The peptides included in the hydrolyzate, forming stable chemical bonds with pectin molecules, not only have a positive effect on the structure, but also increase antioxidant properties, which is promising for the production of bioactive food film coatings that can increase the shelf life of food products.