Transforming the Chemical Functionality of Nanocellulose for Applications in Food Pickering Emulsions: A Critical Review

Pickering emulsions (PEs) have garnered wide attention due to their high physical stability as bioactive carrier agents in the food industry. PEs are highly stable against coalescence due to the irreversible adsorption of particles forming a physical barrier at the oil-water interface between the droplets. As a sustainable alternative to conventional emulsifiers, there is an increasing interest in developing food-grade colloidal particles by forming PEs. Cellulose-based nanoparticles have proven to be efficient materials due to their renewable, biodegradable, non-toxic and controllable surface-active characteristics. Nanocellulose can be modified by various topochemical functionalization to modulate wettability and stimuli-responsive behaviour, endowing its vast potential as Pickering stabilisers for food applications. This review highlights the recent studies of protein functionalized nanocellulose for stabilising food PEs. We hope this review will assist in improving the performance and development of nanocellulose in PEs, which is vital for developing new functional foods and delivery systems.