The synthesis of novel functional materials from abundant food waste resources has great application potentials and ecological benefits. Nanocellulose is a renewable and sustainable polymer that possesses a modifiable surface, excellent mechanical strength, and high aspect ratio, and it is nontoxic. These unique properties garner nanocellulose a promising prospect for multi-various applications including the food industry. This review presents the structural characteristics and advances in the extraction approaches of nanocellulose, with an emphasis in recent progress on the various applications of nanocellulose in the field of food industry. Finally, the environmental and human health issues related to the production of nanocellulose are evaluated. The scheme to extract and produce nanocellulose from food wastes provides a platform for the sustainable utilization of waste biomass. These nanocelluloses exhibit excellent performances in green food packaging materials, emulsion stabilizers, dietary fiber, nutrition delivery and food three-dimensional (3 D) printing hydrogels. To ensure the security and regulatory issues, validated standards to characterize the structure and evaluate its toxicity are still indispensable to achieve the commercialization of nanocellulose in the food industry.

Cellulose nanofiber (CNF) is renowned for its renewable nature, biocompatibility, and high bioavailability, making them a valuable resource within the food industry. The CNF serves as effective stabilizers in emulsions and hydrogels, with their functionality significantly enhanced through modification and functionalization processes. CNF demonstrates considerable promise in the development of intelligent food packaging and food coatings and in the encapsulation and delivery of active ingredients. This article provides an overview of the research achievements on Web of Science since 2018 and briefly outlines the preparation methods of CNF, including chemical, enzymatic, ionic liquid pretreatment, and mechanical treatments. Furthermore, the current application status of CNF in the food sector is described in detail. It further identifies the technical hurdles associated with CNF utilization, addressing concerns related to energy consumption and pollution during its production, as well as the potential toxicity that may arise during the preparation process and subsequent food industry applications. By highlighting these challenges and concerns, the paper aims to guide future research directions for the application of CNF in the food domain.

As a distinctive biphasic gel system, bigel elaborately combines the advantages of hydrogels and oleogels, exhibiting excellent amphiphilicity, softness, and high biocompatibility. Bigel also possesses a certain degree of plasticity and mechanical strength, thereby offering a broad application prospect in the realm of food 3D printing. This article begins with a comprehensive overview of the structural composition of food bigel and the influencing factors, discussing their feasibility and current practical applications of bigel inks in food 3D printing. Specifically, the oleogel phase and the hydrogel phase of the bigel collaborate to construct a gel network with superior physical stability and rheological properties, making it an ideal 3D printing ink. In the realm of food technology, 3D‐printed bigels serve a versatile role not only as carriers for functional ingredients but also as eco‐friendly substitutes for plastic fats, as specialized formulations for dysphagia‐friendly diets, and as innovations in smart food packaging systems. Future research could further exploit the unique functional advantages of bigels by optimizing the gel phase formation process, overall design, and the substances they encapsulate, as well as employing derivative printing techniques. This could provide innovative solutions for the development of new food resources in the future.