Recent Advances in Cellulose-Based Hydrogels: Food Applications

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, biodegradability, 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 cellulose-based hydrogels in the food processing sector. In addition, information regarding the improvement of edible and functional CBHs was discussed, along with potential research opportunities and possibilities. Finally, CBHs could be effectively used in the industry of food processing for the aforementioned reasons.

Keywords: biodegradation; cellulose-based hydrogels (CBHs); food industry; food packaging; functional food.

Figure 1

Cellulose sources for hydrogel production (A), and modification of bacterial cellulose using (B) ex situ and (C) in situ methods. Figure 1A is adapted from Chen et al. [41] and is an open access article (Copyright © 2022 by authors) distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license, while Figure 1 (B and C) is adapted with permission (Copyright © 2019 Springer Nature Switzerland AG, Cham, Switzerland) from Sabbagh et al. [42].

Figure 2

Classification of hydrogels. Figure 2 is adapted with permission (Copyright © 2022 Elsevier B.V., Amsterdam, The Netherlands) from Hasan et al. [44].

Figure 3

Different crosslinking methods used to produce hydrogels. Figure 3 is adapted from George et al. [78] and is an open access article (Copyright © 2019 by authors) distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license.

Figure 4

Applications of cellulose-based hydrogels (CBHs) in different fields. Figure 4 is adapted with permission (Copyright © 2010 Elsevier Ltd., Amsterdam, The Netherlands) from Chang and Zhang [163].