Review on fat replacement using protein-based microparticulated powders or microgels: A textural perspective

Abstract

Background: Due to the growing rise in obesity and food-linked diseases, the replacement of calorie-dense fat has been a key focus of food industries in the last few decades with proteins being identified as promising fat replacers (FRs).

Scope and approach: This review aims to provide an overview of animal and plant protein-based FR studies that have been performed in the last 5 years. Protein isolates/concentrates, their microparticulated forms and protein microgels in model and real foods have been examined. Special emphasis has been given on the characterisation techniques that have been used to compare the full fat (FF) and low fat (LF) versions of the foods using FRs.

Key findings and conclusions: Microparticulated whey protein (MWP) has been the preferred choice FR with some success in replacing fat in model foods and dairy applications. Plant proteins on the other hand have attracted limited research attention as FRs, but show success similar to that of animal proteins. Key characterisation techniques used to compare full fat with low fat products containing FRs have been apparent viscosity, texture profile analysis, microscopy, particle size and sensory properties with oral tribology being a relatively recent undertaking. Coupling tribology with adsorption techniques (muco-adhesion) can be effective to bridge the instrumental-sensory property gap and might accelerate the development cycle of designing low/no fat products. From a formulation viewpoint, sub-micron sized microgels that show shear-thinning behaviour and have boundary lubrication properties offer promises with respect to exploiting their fat replacement potential in the future.

Keywords: Fat mimetic; Fat replacer; Microgels; Microparticulated; Plant protein; Tribology.

Graphical abstract

Fig. 1

Number of publications (bars) and citations (lines) of fat replacers (black bar, solid line) and protein-based fat replacers (white bar, dashed line) using search engine, Web of science (ISI) from 1999 to 2018.

Fig. 2

Scanning electron micrographs (SEM) of microparticulated proteins; (a) microparticulated whey protein (MWP), (Liu, Tian, Stieger, van der Linden, & van de Velde, 2016c), (b) microparticulated egg white protein MEWP) (Liu et al., 2018a), (c) microparticulated soy protein (MSP) (Zhang et al., 2020b) and (d) microparticulated hemp protein (MHP) (Beran et al., 2018). Micrographs are reproduced with permission from Elsevier (a, c), J-STAGE (free access) (b) and Longdom Publishing SL (open access) (d).

Fig. 3

Atomic force microscopy (AFM) images of whey protein microgel particles obtained by a (a) top down (Andablo-Reyes et al., 2019), reproduced with permission from RSC (open access) or (b) bottom approaches (Bahri et al., 2019), reproduced with permission from Elsevier.

Fig. 4

Bubble plot illustrating the characterisation techniques, protein types used as fat replacers including microgels with applications in real or model systems discussed in the review, where n = number of studies (see Supplementary Table S1) for raw data.