Effect of whey protein isolate addition on thermoplasticized pectin packaging properties

Abstract

AbstractPectin is a natural polysaccharide from plants and the peel of some fruits and is available as a byproduct from the fruit juice industry. Whey protein isolate (WPI) is available as a byproduct of cheese production. Both the pectin and WPI are biodegradable polymers, atoxic, biocompatible, and not expensive. The aim of this article was the study the effect of the WPI addition (0, 5, 10, 15, and 20 wt%) on thermoplasticized extruded/thermo‐compressed pectin film (TPP). The films were compact and homogenous and did not present statistical differences in mechanical properties, independent of WPI concentration. Furthermore, infrared spectra of the samples with WPI presented an indication of Maillard reaction by the characteristic presence of melanoidin, which was also observed in colorimetric results. Thermogravimetric results indicated the samples were thermal stable with the increase of WPI amount. Moreover, the barrier properties and contact angles suggested the films presented major barrier properties and hydrophilic surfaces for samples with WPI. Finally, the addition of WPI in TPP resulted in a potential material for applications in several industries.Practical applicationsPectin and whey protein isolate (WPI) are biodegradable polymers and byproducts of the food industry. The aim of this article was the study the effect of the WPI addition on thermoplasticized extruded/thermo‐compressed pectin film (TPP), in other words, packagings produced by the industrial method. The samples with WPI presented an indicative of Maillard reaction by the presence of melanoidin, which was also observed in color. The addition of WPI in TPP resulted in a potential material for applications in several industries.