Food texture perception

Edwards, M. 1999. Vegetables and fruit. In Food Texture Perception and Measurement (A.J. Rosenthal, ed.) pp. 259-281. Aspen Publishers, Gaithersburg, Md. 

Some pioneering work has been done on the effect of particle size on mouthfeel and texture perception (31). When particles of food materials are smaller than 0.1 ]lni they impart no sense of substance and the consumer calls the product watery. Particles of 0.1—3.0 ]lni are sensed as a smooth rich fluid, but when the particles exceed 3 ]lni the food is perceived as chalky or powdery. By controlling particle size, deskable creaminess can be obtained (32). 

Multiple senses, including taste, contribute to our total perception of food. Our perception of the flavor of food is a complex experience based upon multiple senses taste per se, which includes sweet, sour, salty and bitter olfaction, which includes aromas touch, also termed mouth feel , that is, texture and fat content and thermoreception and nociception caused by pungent spices and irritants. Taste proper is commonly divided into four categories of primary stimuli sweet, sour, salty and bitter. One other primary taste quality, termed umami (the taste of L-glutamate), is still somewhat controversial. Mixtures of these primaries can mimic the tastes of more complex foods. 

Lurie, S. and Nussinovitch, A. 1996. Compression characteristics, firmness, and texture perception of heat treated and unheated apples. Int. J. Food Sci. Tech. 31 1-5. 

Clearly, it may be possible to define and accurately measure many aspects of the mechanical and rheological properties of foods, but to try and relate these measures to consumer perceptions of the texture of the foods, is fraught with difficulties. Conversely, it is possible to train human subjects to assess textural characteristics of foods in defined and consistent ways (training them to mimic an instrumental response), however this may be missing the diversity of perceptions of food texture experienced by normal consumers. 

Fig. 1 shows, at low magnification, particles of Gouda cheese expectorated after 5 chews. Clearly in this short time span the first subject (top half) has saturated the sample more completely with saliva and caused more extensive melting of the fat, than the second subject (lower half). Such factors may greatly influence the subjects perceptions of the textural character of the cheese. From examination of mastication patterns it may be possible to determine which factors are influential in assessment of food texture. 

DIFFERENCES BETWEEN INDIVIDUALS IN PERCEPTIONS OF FOOD TEXTURE. 

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... 

Bagley (1983) and Blanshard and Lillford (1987) dealing with qualitative structure-property relationships in meats, plant foods and baked products]. Evidence is now accumulating that structure does play a key role in controlling many other attributes important in foods beyond their basic physical or engineering properties. For example, structure is critical in texture perception (Hutchings and Lillford 1988), flavor release (Taylor 2002) and the bioavailability of some nutrients (Aguilera 2005). 

Notwithstanding all the limitations involved, the continuous improvement in precision and reproducibility of physical measurement equipment that relate to parameters perceived by human subjects make their use straightforward and they can provide consistent results. It is important to keep in mind that although instruments allow precise and objective measurements if applied to whole foods, they only can account for the initial structural properties contributing to texture perception. A correlative approach using sensory and instrumental techniques is often necessary. Indeed, there is no reason to determine accurately a mechanical property if it is not relevant to human sensory perception. Sensory methods become essential when calibrating instrumental equipment and are fundamental in product development, especially at early stages. 

Dobraszczyk, B.J. and Vincent, J.EV Measurement of mechanical properties of food materials in relation to texture the materials approach. Food Texture Measurement and Perception, A.J. Rosenthal, ed.. Aspen Publishers Inc., Gaithensburg, 1999, chap. 5. 

A. J. Rosenthal, ed. Food Texture Measurement and Perception. Aspen, Gaithersburg, 1999. 

Food texture is measured by sensory analysis or by an instrumental method. Using a human inspector for a textural evaluation is subject to some errors because of variations in perception, even when trained panelists are used and a well-defined standard is referenced. However, Katz and Labuza (1981) compared sensory results and cohesiveness values from force-deformation curves for potato chips, popcorn, puffed corn curls as well as saltines, and obtained a good agreement between the two sets of data. A similar comparison was made by van Loon et al. (2007) for the crispness of French fries comparable results were also noted. 

Hutchings, S. C., Foster, K. D., Grigor, J. M. V., Bronlund, J. E. and Morgenstem, M. P. (2014). Temporal dominance of sensations A comparison between younger and older subjects for the perception of food texture. Food Quality and Preference, 31, 106—115. 

Mioche, L., Bourdiol, P. and Monier, S. (2002). Changes in chewing behavior induced by aging and consequences in texture perception during meat consumption. In Degraaf (ed.) Tenth Food Choice Conference. Wageningen, The Netherlands. 

The sensory perception of food texture is significantly dependent on the structure of the system (e.g. the nature of the three-dimensional units produced and the nature of the gel produced in the system) as vell as its rheological behaviour. 

Feeding and texture of food (meeting), Vincent J.F.V, Cambridge UP, 1991, 60 Food texture measurement and perception, Rosenthal A.J, Aspen PubL, 1999, 142 Food texture Instrumental and sensory measurement (meeting), Moskowitz H.R,... 

The sensory perception of food texture is significantly dependent on the structure of the system (e.g. the nature of the three-dimensional units produced and the nature of the gel produced in the system) as well as its rheological behavior. In a multiphase food product, such as an oil-in-water emulsion that contains surfactants for emulsification and polysaccharides that are added to reduce creaming, it is essential to relate the structure of the system to its rheology. This allows one to define the quality of the product in terms of its sensorial function (texture and consistency) as well as its technical function such as flow, dosing and storage stability [32]. 

The aroma of fmit, the taste of candy, and the texture of bread are examples of flavor perception. In each case, physical and chemical stmctures ia these foods stimulate receptors ia the nose and mouth. Impulses from these receptors are then processed iato perceptions of flavor by the brain. Attention, emotion, memory, cognition, and other brain functions combine with these perceptions to cause behavior, eg, a sense of pleasure, a memory, an idea, a fantasy, a purchase. These are psychological processes and as such have all the complexities of the human mind. Flavor characterization attempts to define what causes flavor and to determine if human response to flavor can be predicted. The ways ia which simple flavor active substances, flavorants, produce perceptions are described both ia terms of the physiology, ie, transduction, and psychophysics, ie, dose-response relationships, of flavor (1,2). Progress has been made ia understanding how perceptions of simple flavorants are processed iato hedonic behavior, ie, degree of liking, or concept formation, eg, crispy or umami (savory) (3,4). However, it is unclear how complex mixtures of flavorants are perceived or what behavior they cause. Flavor characterization involves the chemical measurement of iadividual flavorants and the use of sensory tests to determine their impact on behavior. 

Different polysaccharides change the perception of flavour, thus xanthan is superior to gum guar in the perception of sweetness. Mixtures of xanthan and locust bean gum have improved flavour release and texture when used in pies and pat s compared to starch. Many foods are emulsions, examples being soups, sauces and spreads. Exopolysaccharides are used to stabilise these emulsions and prevent the phases from... 

Food colorants play an important role in quality perception. Color is often the first notable characteristic of a food and it influences the expectations of consumers buying the product and also influences food handlers who make quality-related decisions, for example, during visual inspections." More specifically, color predetermines our expectations and perceptions of flavor and taste. " Color is interrelated with flavor intensity (detection threshold), with sweetness and salinity sensations, and also with our susceptibilities to and preferences for products. For example, consumers perceived a strongly red-colored strawberry-flavored drink to be sweeter than a less colored version, and yellow was associated with lemon and pink with grapefruit, but by reversing the colors, flavor perception changed." If food color is not appealing, consumers will not enjoy the flavor and texture of the food. ... 

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