Foods 2023, 12, 350. https://doi.org/10.3390/foods12020350 www.mdpi.com/journal/foods Review Recent Advances in Cellulose-Based Hydrogels: Food Applications Pinku Chandra Nath 1 , Shubhankar Debnath 1 , Minaxi Sharma 2 , Kandi Sridhar 3 , Prakash Kumar Nayak 4, * and Baskaran Stephen Inbaraj 5, * 1 Department of Bio Engineering, National Institute of Technology Agartala, Jirania 799046, India 2 Haute Ecole Provinciale de Hainaut-Condorcet, 7800 Ath, Belgium 3 Department of Food Technology, Karpagam Academy of Higher Education (Deemed to be University), Coimbatore 641021, India 4 Department of Food Engineering and Technology, Central Institute of Technology Kokrajhar, Kokrajhar 783370, India 5 Department of Food Science, Fu Jen Catholic University, New Taipei City 242062, Taiwan * Correspondence: pk.nayak@cit.ac.in (P.K.N.); sinbaraj@yahoo.com or 138547@mail.fju.edu.tw (B.S.I.) Abstract: In the past couple of years, cellulose has attracted a significant amount of attention and research interest due to the fact that it is the most abundant and renewable source of hydrogels. With increasing environmental issues and an emerging demand, researchers around the world are focusing on naturally produced hydrogels in particular due to their biocompatibility, biodegrada- bility, and abundance. Hydrogels are three-dimensional (3D) networks created by chemically or physically crosslinking linear (or branching) hydrophilic polymer molecules. Hydrogels have a high capacity to absorb water and biological fluids. Although hydrogels have been widely used in food applications, the majority of them are not biodegradable. Because of their functional characteristics, cellulose-based hydrogels (CBHs) are currently utilized as an important factor for different aspects in the food industry. Cellulose-based hydrogels have been extensively studied in the fields of food packaging, functional food, food safety, and drug delivery due to their structural interchangeability and stimuli-responsive properties. This article addresses the sources of CBHs, types of cellulose, and preparation methods of the hydrogel as well as the most recent developments and uses of cel- lulose-based hydrogels in the food processing sector. In addition, information regarding the im- provement of edible and functional CBHs was discussed, along with potential research opportuni- ties and possibilities. Finally, CBHs could be effectively used in the industry of food processing for the aforementioned reasons. Keywords: cellulose-based hydrogels (CBHs); food industry; functional food; biodegradation; food packaging 1. Introduction Gels are networks of polymers that are swollen by a large amount of solvent and have three dimensions. Hydrogels are structures that are mostly made of biopolymers and/or polyelectrolytes and retain a great amount of water [1]. According to the source, there are two types of hydrogels: those that are made from natural polymers and those that are made from synthetic polymers. Based on cross-linking, hydrogels can be put into two groups: chemical gels and physical gels. Physical gels are made when molecules stick together on their own through ionic or hydrogen bonds. Chemical gels are made when molecules stick together through covalent bonds [2]. The first hydrogels were described by Wichterle and Lim [3]. Notably, hydrogels have several potential uses in the fields of food, agriculture, water purification and biomaterials, etc. Recently, researchers have ac- tively contributed to the development of innovative hydrogels for implementations such Citation: Nath, P.C.; Debnath, S.; Sharma, M.; Sridhar, K.; Nayak, P.K.; Inbaraj, B.S. Recent Advances in Cellulose-Based Hydrogels: Food Applications. Foods 2023, 12, 350. https://doi.org/10.3390/foods12020350 Academic Editors: Sara Ghorbani Gorji and Paul J.A. Sobral Received: 3 December 2022 Revised: 6 January 2023 Accepted: 9 January 2023 Published: 11 January 2023 Copyright: © 2023 by the authors. Li- censee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and con- ditions of the Creative Commons At- tribution (CC BY) license (https://cre- ativecommons.org/licenses/by/4.0/).