Marrying oral tribology to sensory perception: a systematic review

Abstract

Oral tribology is rapidly entering into the food scientists' toolbox because of its promises to predict surface-related mouthfeel perception. In this systematic review, we discuss how oral tribology relates to specific sensory attributes in model and real foods focussing on recent literature from 2016 onwards. Electronic searches were conducted in four databases, yielding 4857 articles which were narrowed down to a set of 16 articles using pre-specified criteria. New empirical correlations have emerged between friction coefficients in the mixed lubrication regime and fat-related perception (e.g. smoothness) as well as non-fat-related perception (e.g. pastiness, astringency, stickiness). To develop mechanistically supported generalized relationships, we recommend coupling tribological surfaces and testing conditions that are harmonized across laboratories with temporal sensory testing and multivariate statistical analysis.

Graphical abstract

Figure 1

PRISMA flow-chart of the study selection procedure for qualitative synthesis of articles in the tribology–sensory area published in 2016 and onwards.

Figure 2

Schematic illustration of different tribometers that are used in the area of food research (a) showing a Mini-traction-machine (MTM) with PDMS ball-on-PDMS disc set-up, where U_B and U_D are the speeds of the ball and disc, respectively and W is the load, i) (redrawn from Ref. [6^•]), a Tribo-rheocell accessory that is a ball-on-three plate set-up as an attachment to a controlled stress rheometer, ii) (redrawn from Ref. [30]), an optical tribological configuration (OTC), where F is the frictional force, iii) (redrawn from Ref. [31]), a lab-modified texture analyser with steel ball-on-PDMS disc set-up, iv) (redrawn from Ref. [32]); and a typical Stribeck curve showing the friction coefficient (μ) between surfaces as a function of the combined lubrication parameters of the lubricant viscosity (η), entrainment speed (U) and load (W), (b) (redrawn from Refs. [11^••,14^•]).

Figure 3

Schematic representation of qualitative clusters on correlations between instrumental and sensory parameters for different model and real products, based on studies reported in Table 1. Here μ, η and d₃₂ represent the friction coefficient, viscosity and mean particle size, respectively. The subscripts for μ and η are the speed (mm/s) and shear rate (s⁻¹), respectively.