Carbohydrate-based fat mimetics: A focus on fat-mimicking mechanisms and a tribology perspective

Background

Fat mimetics such as inulin can effectively reduce fat in foods while simulating the fat-like taste and texture. However, there are still significant gaps between fat mimetics and real fat in terms of flavor and texture, and the research of fat-mimicking mechanisms is also insufficient. Therefore, uncovering the mechanism of action of fat mimetics in simulating fat structures is particularly important. This is key to improving their design, enhancing simulation effects, and advancing low-fat, healthy food development to promote public health.

Scope and approach

This review aims to provide an overview of research on carbohydrate-based fat mimetics and the related mechanism. They were summarized as the three-dimensional network structure and microparticulate hypothesis. Furthermore, based on tribology, we proposed a new mechanism in terms of structural strain, oral processing, and sensory perception.

Key findings and conclusions

Carbohydrate-based fat mimetics form a three-dimensional gel network that stabilizes water and provides fat-like lubricity. Meanwhile, natural or processed carbohydrates can form tiny particles that mimic fat globules and replicate fat's smooth texture. Notably, their unique structure enables thixotropic fluid behavior, exhibiting "elastic-sliding-adhesion" strain under chewing forces. This facilitates transitions between boundary, mixed, and hydrodynamic lubrication states, as shown by oral friction coefficient curves. Integrating oral lubrication models with sensory evaluations reveals the mechanisms of smoothness and thickness perception. In a word, this review highlights the dynamic oral processing characteristics of fat mimetics and expands the understanding of fat simulation mechanisms from static rheological models to dynamic tribological frameworks.