Lubrication plays an important role not only in mechanical systems, but also in biological and consumer-product interfaces, including foods, pharmaceuticals, cosmetics and personal care. In food systems, oral lubrication strongly influences texture, mouthfeel and consumer acceptance, particularly in products reformulated to reduce fat or increase protein content. However, reduced-fat and high-protein foods often suffer from dryness, roughness, poor creaminess and protein-induced astringency, especially when plant proteins are used. Here, we present a plant protein-based aqueous lubrication platform designed to improve oral lubrication and sensory performance in reduced-fat and high-protein foods. The technology is based on protein microgels embedded and intermittently coated within a polysaccharide hydrogel network, creating a microgel-reinforced architecture that promotes interfacial sliding, efficient boundary lubrication and desirable textural properties [1,2]. This approach enables enhanced mouthfeel using a water-based, clean-label and potentially more sustainable formulation strategy, reducing reliance on high levels of fat to deliver creaminess and lubrication. A multiscale characterisation strategy was used to investigate the structural, physicochemical and tribological behaviour of the system, including dynamic light scattering, electron microscopy, rheology, tribology and adsorption analyses. The materials achieved friction coefficients as low as 0.0003–0.01 on both smooth and biomimetic tongue surfaces, demonstrating superlubricity under physiologically relevant oral conditions [2,3]. The platform was shown to be versatile across both dairy and plant based proteins, combined with polysaccharides such as xanthan gum. Application studies in reduced-fat and high-protein formulations demonstrated improved mouthfeel, enhanced lubrication and reduced perceived astringency without compromising nutritional quality [2]. Overall, this work highlights the relevance of tribology beyond conventional machinery applications and demonstrates how sustainable aqueous lubrication strategies can support healthier, protein-enriched and reduced-fat foods with improved consumer acceptance.

[1] Hu, Sarkar et al. (2020). ACS Macro Lett, 9, 12, 1726–1731.

[2] Pabois, Sarkar et al. (2024). Commun. Mater. 5, 158.

[3] Andablo-Reyes, Sarkar et al. (2020). Appl. Mater. Interfaces. 12, 44, 49371–49385.