Utilizing sodium caseinate and/or whey protein isolate to create edible films that can be used as packaging materials

Abstract

To assess their potential for use in environmentally friendly packaging solutions, this thesis investigates the production and characterization of edible films made from sodium caseinate (NaCas) and/or whey protein isolate (WPI) with glycerol acting as a plasticizer. The main goal of the present study was to form and evaluate biodegradable films utilizing sodium caseinate (NaCas) and whey protein isolate (WPI) by employing glycerol as a plasticizer. Also, this study investigates how, in various environmental circumstances, glycerol concentration affects the mechanical and barrier qualities of these protein-based films. Comprehensive experimental evaluations show that WPI and NaCas films behave differently in terms of water vapor permeability, mechanical strength, and optical characteristics. Comparing NaCas with WPI films using colorimetric analysis, the former shows greater lightness and a stronger yellow tint, indicating differences in the ways that the protein structures interact with glycerol. These results are corroborated by spectrophotometric studies, which show that NaCas coatings enhance their yellow hue by absorbing more at the blue wavelength. The globular protein structures of WPI films, which may form more cohesive networks when plasticized with glycerol, are responsible for their continuous superior elongation and stress resistance, as demonstrated by mechanical testing conducted at different humidity levels. On the other hand, NaCas films might be favored in applications that demand less flexibility and more stiffness despite their lower mechanical strengths. Water vapor permeability tests demonstrate the compromises between mechanical flexibility and moisture barrier effectiveness by pointing out that WPI films perform less well at the barrier than NaCas. WPI films are most likely better appropriate for applications requiring a higher mechanical strength, such as long-lasting packaging solutions that may be subjected to physical strains while being stored or transported. NaCas films may nevertheless be appropriate for applications where biodegradability, barrier properties, or affordability are more crucial than strength despite their decreased stress resistance. In conclusion, these edible films can be used in many different food products applications within the food packaging sector. Dairy Products, Meat, Chicken, and Seafood are a few examples.