Food texture, definition

Describes food texture and viscosity including the definition of TPA characteristics using the GF Texturometer and the Instron. 

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. 

This definition recognizes three essential elements of texture that it is a sensory quality that it stems from structural parsuneters of foods and that it is a composite of several properties. Consideredjle efforts have been made to understand more clearly the complex nature of texture and texture-forming... 

Emulsions are colloidal dispersions of liquid droplets in another liquid phase, sometimes stabilized by surface active agents. Emulsions thus consist of a discontinuous phase, dispersed in a continuous phase. The most common types of emulsions are water-in-oil (W/O) in which oil is the continuous phase, and oil-in-water (OAV) in which water forms the continuous phase. However, this traditional definition of an emulsion is too narrow to include most food emulsions. For example, in foods the dispersed phase may be partially solidified, as in dairy products or the continuous phase may contain crystalline material, as in ice cream. It may also be a gel, as in several desserts. In addition to this, air bubbles may have been incorporated to produce the desired texture. 

Unlike other manufacturing industries, where the produet ean be accurately specified in terms of its performance, food is measured by individuals, and its qualities of appearance, texture and flavour are measured subjeetively against a set of criteria established by experience. We know what we hke, and it is very dependent on our own cultural background and lifestyle. As eonsumers, we detect some qualities instantly with our eyes, nose and mouth, aU of whieh have multiple sensors with stimulus/ response behaviour that is not completely understood. We have to recognise that these qualities are defined subjectively, and are described in words that have, as yet, no clear numerical definition. There are other quaUties such as the efifeet of food on our longer-term health and well-being that as individuals we are not weU equipped to measure. We cannot easily detect the effect of salt on our blood pressure or antioxidants on our cancer resistance. The development of biomarkers for health is outside the scope of this volume. 

The first soybean protein ingredients made commercially available for food use included full-fat and defatted soy flours and grits (3, 7, 8). These products contain ca. 46-59% protein (NX 6.25) on a moisture-free basis and are available with various heat treatments for specific end-use. Soy protein concentrates and soy protein isolates were introduced into the market about 15 years ago (3, 9, 10, II). By definition soy protein concentrates must contain no less than 70% protein (N X 6.25) and isolates no less than 90% protein (N X 6.25), all on a moisure-free basis. In the past several years there has been much activity in the commercialization of textured soy protein products intended for the extension and replacement of meat. These textured products may be obtained through fiber spinning, shred formation, extrusion, or compaction (12, 13, 14, 15). In addition, soybean milk solids and the heterogeneous proteins in soybean whey might serve as useful substrates in chemical modifications for food use. This short recitation of commercial products illustrates the type of crude protein fractions available for practical modification. Many useful functional properties have been ascribed to these new food proteins. 

Definition Mixture of D-glucose, maltose, and maltodextrins obtained by partial hydrolysis of corn starch Properties Aq. syrup Toxicoiogy May cause allergic reaction Uses Nutritive sweetener, dietary supplement, thickener, bodying agent, texturizer, carrier in foods, soft drinks feedstock in fermentation sweetener in pharmaceutical orals in aspirin humectant, solvent in cosmetics Reguiatory FDA 21CFR 131.112, 133.124, 133.178, 133.179, 145.3, 145.134, 145.180,... 

Synonyms Hydrolysates, oat flour Oat flour, hydrolysates Oat flour, hydrolyzed Definition Hydrolysate of oat flour derived by acid, enzyme, or other method of hydrolysis Uses Hair conditioner, skin conditioner in cosmetics fat replacer for low-fat foods, baked goods, salad dressings, etc. thickener, texturizer in foods... 

CAS 26446-38-8 EINECS/ELINCS 247-706-7 Synonyms p-D-Fructofuranosyl-a-D-glucopyranoside monohexadecanoate a-D-Glucopyranoside, p-D-frutofuranosyl, monohexadecanoate Palmitic sucrose ester Saccharose palmitate Sucrose monopalmitate Sucrose palmitic acid ester Definition Monoester of palmitic acid and sucrose Empirical C28HS2O12 Properties M.w. 580.71 nonionic Uses O/w and w/o emulsifier, softener, conditioner, texturizer, and aerating agent in foods protective fruit coatings emulsifier, solubilizer, stabilizer, tablet lubricant, excipient, diluent for pharmaceuticals emulsifier, surfactant, solvent in cosmetics poiymerization emulsifier for food-pkg. film... 

The terms nourishment and enjoyment introduce two important properties of foods the nutritional value and the hedonic value. The former is relatively easy to quantify since all the important nutrients are known and their effects are defined. Furthermore, there are only a limited number of nutrients. Defining the hedonic value of a food is more difficult because such a definition must take into account all those properties of a food, such as visual appeal, smell, taste and texture, which interact with the senses. These properties can be influenced by a large number of compounds which in part have not even been identified. Besides their nutritional and hedonic values, foods are increasingly being judged according to properties which determine their handling. Thus, the term convenience foods . An obvious additional requirement of a food is that it be free from toxic materials. 

The term emulsifier is often used ambiguously or incorrectly in the food industry. In addition to its definition as a substance that promotes emulsion formation by interfacial action, it is also used to describe materials that promote the shelf-life of foods in other ways, or that simply change the texture or mouth-feel of some foods. 

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