Sesame protein based edible films: Development and characterization

Sesame protein isolate prepared from defatted sesame meal can be used as a valuable source for edible film formation. Edible films from sesame protein isolate were prepared and effect of protein concentration (3-9%), pH (9-12), temperature (70-90 degrees C) and plasticizer (10-50% on a protein basis) were evaluated. Response surface methodology (RSM) was employed for optimization of parameters for preparation of edible film and optimized film was further characterized. Water vapor permeability (WVP), tensile strength and solubility were considered as response variables. All independent variables (protein concentration, pH, temperature and plasticizer) significantly (p < 0.05) affected the water vapor permeability, tensile strength and solubility of edible films. WVP of edible films ranged from 0.90 to 1.62 x 10(-11) g m/Pa.s.m(2), tensile strength from 0.47 MPa to 3.03 MPa, and solubility from 51.06 to 87%. Optimized values indicated that the edible films prepared at protein concentration of 9%, pH 12, temperature 90 degrees C and plasticizer 10% (on protein basis) resulted in lower water vapor permeability, maximum tensile strength and lower solubility. DSC curve of film exhibited single Tg of 50 degrees C. TGA scans for optimized film evinced good thermal stability. Film exhibited weight loss in three stages (temperature ranged between 150 degrees C and 590 degrees C). The XRD of film displayed only one main crystalline reflection at 2 theta(0) which indicates the major structure of films was amorphous. (C) 2016 Elsevier Ltd. All rights reserved.