Food texture modeling

In contrast to the mechanical and rheological properties of materials, which have defined physical meanings, no such definitions exist for the psychophysical assessment of equivalent textural properties of foods. To identify material properties, or combinations of these, which are able to model sensory assessments requires a mixture of theory and experimentation. Scientific studies of food texture began during the twentieth century by the analysis of the rheological properties of liquid or semi-solid foods. In particular Kokini14 combined theoretical and experimental approaches in order to identify appropriate rheological parameters from which to derive mathematical models for textural attributes of liquid and semi-solid foods, namely, thickness, smoothness and creaminess. 

The next area of future development is microstructure analysis. Although numerous attempts have been made to connect crystal stmcture to food texture, a long road still remains ahead before it can be said that a certain type of stmcture leads definitively to certain mechanical properties. Development of methodologies for structure analysis and further developments in analytical modeling of crystalline microstructure are needed. Further, the connection between these microstructural models and food properties related to the crystalline microstructure are important. 

Cutler, A. N., Morris, E. R., and Taylor, L. J. 1983. Oral perception of viscosity in fluid foods and model systems. J. Texture Stud. 14 377-395. 

Moyano, P. C., Troncoso, E., Pedreschi, F. (2007). Modeling texture kinetics during thermal processing of potato products. J. Food Sci., 72, E102-E107. 

A considerable problem for both the food industry and sensory scientists is the degree of individual variation in texture perceptions. The differences in breakdown pathways in the mouth for standard samples may underlie some of the variability. Indeed Brown et al31 have demonstrated an influence of chewing behaviour on texture perceptions in a model food system. Even if all individuals shared a common system for assessing a particular textural characteristic, the differences in the way they masticate a sample may cause them to come to different conclusions regarding its texture. However, there is also the real possibility that subjects may use different measuring systems for assessment of a textural characteristic they... 

We can determine what features of the chewing sequence influence assessment of particular textural characteristics of food by using this approach to examine the interaction between food and consumer during the mastication process. We should then be able to develop mathematical models for perception of textural qualities which take into account different texture combinations (for example, assessment of hardness in both elastic and brittle foods), and different breakdown patterns. Although currently at an early stage, mastication analysis shows promise for enhancing our measurement of perceived texture in foods. 

Figure 8-32 Mechanical Model for Foods as Viscoplastic Materials. Source From M. Tanaka, et al., Measurement of Textural Properties of Foods with a Constant Speed Cone Penetrometer, J. Texture Studies, Vol. 2, pp. 301-315, 1971.

Jones, P.R., Gawel, R., Francis, I.L., Waters, E.J. (2008). The influence of interactions between major white wine components on the aroma, flavour and texture of model white wine. Food Qual. Prefer, 19, 596-607... 

Holdsworth, S. D. 1971. Applicability of rheological models to the interpretation of flow and processing behavior of fluid food products. J. Texture Stud. 4 393-418. 

Ofoli, R. Y., Morgan, R. G., and Steffe, J. F. 1987. A generalized rheological model for inelastic fluid foods. J. Texture SUid. 18 213-230. 

Kokini, J. L. and Dickie, A. 1981. An attempt to identify and model transient viscoelastic flow in foods. J. Texture Stud. 12 539-557,... 

Swyngedau s equation has proven to be a good model descriptor of food powder agglomerate compression (Yan and Barbosa-Canovas, 1997, 2000). Yan and Barbosa-Canovas (1997) converted the Swyngedau model into Equation 17, which allows for the direct use of force-deformation readings recorded from a TA-TX2 texture analyzer. 

The subsequent step consists in training assessors to rate the perceived intensity of some descriptors of foods on an evaluation scale. Panelists learn to quantify their perception, initially by ranking series of single odor or taste or texture stimuli with respect to the intensity of a particular characteristic, then quantifying the perception on the evaluation scale. The test samples used are model systems for instance, a single taste or flavor compound in water or other neutral media or solid or semisolid materials differentiated in their texture properties or samples obtained by spiking product samples with a flavor... 

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