Development and characterization of high methoxyl pectin film by using isomalt as plasticizer

Abstract

The aims of this work were to analyze the effects of high methoxyl pectin (HMP) and isomalt concentrations on the physical properties of pectin-based films. Films were developed using HMP (1.5% and 3.0% w/v) and isomalt at different concentrations (0.25%, 0.50%, 0.75%, 1.0%, and 1.50% w/v). The use of isomalt produced an improvement in the physical properties of HMP films. Moisture of films increased and swelling degree decreased with a higher isomalt concentration. Films presented higher water vapor permeability (WVP) with an increase in HMP concentration. Likewise, WVP values decreased with an increase in isomalt concentration. The tensile properties of pectin-based films varied with the use of isomalt. Increasing the amount of isomalt produced more deformable films (elongation at break increased) and led to an increase in the elasticity of HMP films (elastic modulus decreased). The films presented better qualities when obtained from using a 1.5% of HMP and 1.0% of isomalt. Practical applications In food, edible films and coatings can reduce respiration rate, delay moisture migration, and loss of volatile compounds, and delay changes in texture properties. The use of natural materials for the development of edible films and coatings has had a growing scientific and industrial interest, thanks to the wishes of food processors to solve environmental problems related to the elimination of nonbiodegradable packaging materials and the prospects of creating new markets for film formation using underutilized agricultural products. The use of edible coatings and films cannot completely replace traditional packaging materials, but they can become an additional factor for food preservation. With no plasticizer added, the films obtained from many polysaccharides are brittle. Plasticizers, predominantly polyols, enhance the material's elasticity. Isomalt is a sugar alcohol; so, it could be used as a plasticizer.