Texture viscosity

Because the quality and health aspects of foods cannot be measured by a single index, it necessarily follows that the subject of control methods in the canned food industry is very broad, and includes chemical, physical, organoleptic, and bacteriological tests, only the first of which is discussed here. The measurement of color, odor, optical clarity, texture, viscosity, and chemical composition has been used to evaluate canned foods, but in many cases the methods that are applicable to one product are either not applicable to another, or can be used only after considerable modification. 

Lipstick is one of the decorative cosmetic products that command a unique market. Lipstick contains a variety of emollients, emulsifiers, preservatives, colorants and binders [4]. The quality of lipstick is directly linked to the basic material used in the formulation [5-6]. Varying the ratio of the ingredient used in formulation determines the final product characteristic such as texture, viscosity, hardness and melting point of the lipstick [7-9]. 

With the exception of starch, many biopolymers cannot provide nutrition for humans and other omnivorous animals. In human foods biopolymers are used as additives that can improve texture, viscosity, fiber content, and other properties of prepared foods, without providing direct nutritional values. Examples of such utilization are the addition of pectins, agar, and other gums to foods to achieve thickening and gelling effects. Another example of potential large-scale utilization of cell wall biopolymers is the dramatic improvement in the texture and rising of breads prepared from com and other starches by the addition of xylans (78). 

Compared to most white and red wines, Vin Santo wines, and especially the slightly sweet and sweet styles, are characterized primarily by their flavor and taste, rather than their aroma. Accordingly, in addition to sweetness and acidity, the most used descriptors to evaluate Vin Santo in relation to its perception in the mouth are alcoholicity (warm sensation), texture, viscosity, and overall taste persistence. Among the flavor descriptors, those relating to caramelization (like flavors of honey, milk-honey candy, molasses, caramel) are the most used, as these are more suitable to describe the different Vin Santo. It is estimated that these descriptors... 

The influence of the rheology of a particular food material on the perception of its taste or flavor can have two main origins. A physiological effect due to the proximity of the taste and olfactory receptors to the kinesthetic and thermal receptors in the mouth, since then an alteration of the physical state of the material may have an influence on its sensory perception, and an effect related to the bulk properties of the material (e.g., texture, viscosity), since the physical properties of the material may affect the rate and the extent with which the sensory stimulus reaches the gustatory receptors. 

Starch is a natural polysaccharide that can be derived from inexpensive and renewable resources. Starch films and coatings are primarily used for food packaging. Natural and modified starch films are also used to change the physical properties of food products such as soups and meat products by modifying the texture, viscosity, adhesion, moisture retention, and gel formation (Thomas and Atwell, 1997). Starch molecules are composed of two macromolecules namely amylose and amylopectin. Amylose has excellent film-formabihty, and forms odorless, tasteless, and colorless films. The relative amoimt of amylose and amylopectin depends on the plant source and is a key factor in determining the properties of starch. Generally starch contains 20-25% amylose and 75-80% amylopectin (Jimenez et al., 2012). 

Uses Texturizer, viscosity builder, serum formation inhibitor in set or stirred yogurts and dessert prods. texture improver and emulsifier in convenience foods Features Consistent vise, control soluble and gelling over wide pH range exc. flavor profile suitable for vegetarians Regulatory EU compliant Properties Neutral odor and odor... 

In unmodified forms, starches have very limited use in the food industry, but modified starches by disruption of hydrogen bonding or by chemical substitution, have significantly been playing important roles in the food industry. They have been used to modify physical properties of food products such as soups, sauces, snacks, batters and meat products contributing mainly to texture, viscosity, gel formation, adhesion, binding, moisture retention. 

A good compilation of the functions of fats in various food products is available (26). Some functions are quite subtle, eg, fats lend sheen, color, color development, and crystallinity. One of the principal roles is that of texture modification which includes viscosity, tenderness (shortening), control of ice crystals, elasticity, and flakiness, as in puff pastry. Fats also contribute to moisture retention, flavor in cultured dairy products, and heat transfer in deep fried foods. For the new technology of microwave cooking, fats assist in the distribution of the heating patterns of microwave cooking. 

Since the early 1980s, the viscose-based staple fibers have, like the cuprammonium and viscose filament yams in the 1970s, ceased to be commodities. They have been repositioned from the low cost textile fibers that were used in a myriad of appUcations regardless of suitabUity, to premium priced fashion fibers dehvering comfort, texture, and attractive colors in ways hard to achieve with other synthetics. They are stiU widely used in blends with polyester and cotton to add value, where in the 1980s they would have been added to reduce costs. 

Texture also influences the evaluation of taste. Sweetness in a Hquid is associated with body or viscosity. An artificially sweetened beverage that lacks body, therefore, may be rated quaUtatively lower than one equally sweet but containing sucrose. 

The polyamides are soluble in high strength sulfuric acid or in mixtures of hexamethylphosphoramide, /V, /V- dim ethyl acetam i de and LiCl. In the latter, compHcated relationships exist between solvent composition and the temperature at which the Hquid crystal phase forms. The polyamide solutions show an abmpt decrease in viscosity which is characteristic of mesophase formation when a critical volume fraction of polymer ( ) is exceeded. The viscosity may decrease, however, in the Hquid crystal phase if the molecular ordering allows the rod-shaped entities to gHde past one another more easily despite the higher concentration. The Hquid crystal phase is optically anisotropic and the texture is nematic. The nematic texture can be transformed to a chiral nematic texture by adding chiral species as a dopant or incorporating a chiral unit in the main chain as a copolymer (30). 

Acoustic Wave Sensors. Another emerging physical transduction technique involves the use of acoustic waves to detect the accumulation of species in or on a chemically sensitive film. This technique originated with the use of quartz resonators excited into thickness-shear resonance to monitor vacuum deposition of metals (11). The device is operated in an oscillator configuration. Changes in resonant frequency are simply related to the areal mass density accumulated on the crystal face. These sensors, often referred to as quartz crystal microbalances (QCMs), have been coated with chemically sensitive films to produce gas and vapor detectors (12), and have been operated in solution as Hquid-phase microbalances (13). A dual QCM that has one smooth surface and one textured surface can be used to measure both the density and viscosity of many Hquids in real time (14). 

In the confectionery industry, com symps are used extensively in nearly every type of confection, ranging from hard candy to marshmallows. In hard candies, which are essentially soHd solutions of nearly pure carbohydrates, com symp contributes resistance to heat discoloration, prevents sucrose crystallization, and controls hygroscopicity, viscosity, texture, and sweetness. Maltose symps, high conversion symps, and acid-converted symps (36 and 42 DE) are used for this appHcation. 

Sucrose is widely used in the food industry to sweeten, control water activity, add body or bulk, provide crispness, give surface glaze or frost, form a glass, provide viscosity, and impart desirable texture. It is used in a wide variety of products from bread to medicinal symps. 

Com symp soflds are also dry products, have a smaller average size, and are comparatively sweeter (12). Both maltodextrins and com symp soflds are used to prevent caking enhance dispersibiUty and solubiUty provide body or bulk impart deskable texture bind, carry, and protect flavors control extmsion expansion provide viscosity form films and coatings provide an oxygen barrier inhibit crystallization control sweetness improve sheen improve organoleptic characteristics slow meltdown and improve freeze—thaw stabiUty. 

Precipitation and Purification. During the hydrolysis, control tests are made by turbidimetric titration of samples taken intermittently. When the desired degree of hydrolysis is reached, the ester is precipitated from the reaction solution into water. It is important for the precipitate to have the proper texture for subsequent washing to remove acid and salts for thermal stabilization. Before precipitation, the reaction solution is usually diluted with additional aqueous acetic acid to reduce the viscosity. If a flake texture is desired, the solution is poured into a vigorously stirred, 10—15% aqueous acetic acid. To precipitate the acetate in powder form, dilute acetic acid is added to the stirred reaction solution. In both cases, the precipitated ester is suspended in 25—30% aqueous acid solutions and finally washed with deionized water. The dilution, precipitation temperature, agitation, and strength of the acid media must be controlled to ensure uniform texture. 

The rheologically expected complete regeneration of the viscosity after the shearing experiment is not common for these fruit preparations. The reason for this loss of viscosity must be searched for in the destruction of those parts of texture being caused from a gelation process. 

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