polymers Review Protein-Based Films and Coatings for Food Industry Applications Vlad Mihalca 1,† , Andreea Diana Kerezsi 1,2,† , Achim Weber 3 , Carmen Gruber-Traub 3 , Jürgen Schmucker 3 , Dan Cristian Vodnar 1 , Francisc Vasile Dulf 4 , Sonia Ancut , a Socaci 1 , Anca Fărcas , 1 , Carmen Ioana Mures , an 1 , Ramona Suharoschi 1, * and Oana Lelia Pop 1, *   Citation: Mihalca, V.; Kerezsi, A.D.; Weber, A.; Gruber-Traub, C.; Schmucker, J.; Vodnar, D.C.; Dulf, F.V.; Socaci, S.A.; F ˘ arcas , , A.; Mures , an, C.I.; et al. Protein-Based Films and Coatings for Food Industry Applications. Polymers 2021, 13, 769. https://doi.org/10.3390/ polym13050769 Academic Editor: Antonio Zuorro Received: 11 February 2021 Accepted: 25 February 2021 Published: 2 March 2021 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). 1 Department of Food Science, University of Agricultural Science and Veterinary Medicine, 400372 Cluj-Napoca, Romania; vlad.mihalca@yahoo.com (V.M.); andreeadianakerezsi@gmail.com (A.D.K.); dan.vodnar@usamvcluj.ro (D.C.V.); sonia.socaci@usamvcluj.ro (S.A.S.); anca.farcas@usamvcluj.ro (A.F.); carmen.muresan@usamvcluj.ro (C.I.M.) 2 TERRA Research and Teaching Center, Gembloux Agro-Bio Tech, University of Liege, Department of Food Science and Formulation, Passage des Deportes-2, B-5030 Gembloux, Belgium; adkerezsi@uliege.be 3 Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB, Nobelstraße 12, 70569 Stuttgart, Germany; achim.weber@igb.fraunhofer.de (A.W.); carmen.gruber-traub@igb.fraunhofer.de (C.G.-T.); juergen.schmucker@igb.fraunhofer.de (J.S.) 4 Department of Biochemistry, University of Agricultural Sciences and Veterinary Medicine, 400372 Cluj-Napoca, Romania; francisc.dulf@usamvcluj.ro * Correspondence: ramona.suharoschi@usamvcluj.ro (R.S.); oana.pop@usamvcluj.ro (O.L.P.) † These authors contributed equally to this work. Abstract: Food packaging is an area of interest not just for food producers or food marketing, but also for consumers who are more and more aware about the fact that food packaging has a great impact on food product quality and on the environment. The most used materials for the packaging of food are plastic, glass, metal, and paper. Still, over time edible films have become widely used for a variety of different products and different food categories such as meat products, vegetables, or dairy products. For example, proteins are excellent materials used for obtaining edible or non-edible coatings and films. The scope of this review is to overview the literature on protein utilization in food packages and edible packages, their functionalization, antioxidant, antimicrobial and antifungal activities, and economic perspectives. Different vegetable (corn, soy, mung bean, pea, grass pea, wild and Pasankalla quinoa, bitter vetch) and animal (whey, casein, keratin, collagen, gelatin, surimi, egg white) protein sources are discussed. Mechanical properties, thickness, moisture content, water vapor permeability, sensorial properties, and suitability for the environment also have a significant impact on protein-based packages utilization. Keywords: food package; protein; protein films; protein coatings; functionalization; antioxidant; antimicrobial; antifungal 1. Introduction Since ancient times, humans have tried to find optimal solutions for packing their food products as easily and productively as possible. Along with technological advancements, society found better and more resistant materials to improve food packing. As time passed by, the population started to develop alternatives when discussing packaging. In this regard, the research for new, unconventional materials that can be used for packaging food in a more sustainable and eco-friendly way has seen a constant increase in the last few decades. Packaging has many duties such as: to preserve substances against contamination and perishability, to move easily and keep goods, and to give a constant measure of the contents. A package has three important tasks: to protect the contents, to give good marketing to a product, and to deliver useful information to the customer. A fourth purpose is related to advertisement because easy to use packaging increases market opportunities. Polymers 2021, 13, 769. https://doi.org/10.3390/polym13050769 https://www.mdpi.com/journal/polymers