Next Article in Journal
Improvements of Nano-TiO2 on the Long-Term Chloride Resistance of Concrete with Polymer Coatings
Next Article in Special Issue
Microbiological and Physicochemical Properties of Meat Coated with Microencapsulated Mexican Oregano (Lippia graveolens Kunth) and Basil (Ocimum basilicum L.) Essential Oils Mixture
Previous Article in Journal
Synthesis and Characteristics of Zn-Doped CuCrO2 Transparent Conductive Thin Films
Article Menu
Issue 5 (May) cover image

Export Article

Open AccessArticle

Glycerol-Plasticized Films Obtained from Whey Proteins Denatured at Alkaline pH

Department of Chemical Sciences, University of Naples “Federico II”, Complesso Universitario di Monte Sant’Angelo, Via Cinthia 4, 80126 Naples, Italy
Author to whom correspondence should be addressed.
Coatings 2019, 9(5), 322;
Received: 11 April 2019 / Revised: 12 May 2019 / Accepted: 14 May 2019 / Published: 16 May 2019
(This article belongs to the Special Issue Edible Films and Coatings: Fundamentals and Applications)
PDF [1489 KB, uploaded 16 May 2019]


Whey represents the major by-product of cheese industry. One possibility to recycle the whey wastes is the use of their globular proteins as a polymer source for the production of biodegradable plastic materials. Whey protein (WP)-based films are usually obtained by protein heat treatment in the presence of glycerol (GLY) as plasticizer at pH 7, a method which would require commercially high costing process. In this work we explored the possibility of producing manageable whey-derived materials without any heat-treatment but under alkaline conditions. The reported results demonstrated that the casting at pH 12 of the unheated WP film forming solutions (FFSs), containing either 40% or 50% GLY, led to produce more resistant and flexible materials than the ones obtained at pH 7. Film opacity was observed significantly increased, being higher in the samples obtained at alkaline pH without WP heating and with higher GLY concentrations. Finally, moisture content decreased with the reduction of GLY content, both in heated and unheated WP-based films, whereas water uptake of the different films prepared at pH 12 did not significantly change. View Full-Text
Keywords: biodegradable materials; whey; protein-based films biodegradable materials; whey; protein-based films

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Abdalrazeq, M.; Giosafatto, C.V.L.; Esposito, M.; Fenderico, M.; Di Pierro, P.; Porta, R. Glycerol-Plasticized Films Obtained from Whey Proteins Denatured at Alkaline pH. Coatings 2019, 9, 322.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Coatings EISSN 2079-6412 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top