Taste quantitative measurement

There are two types of physical properties qualitative properties and quantitative properties. Qualitative properties are those that caimot be measured, such as smell or taste. Quantitative properties, on the other hand, can be given precise mathematical values, for example, the weight of a certain volume of a substance (density), the temperature at which the substance boils (boiling point), or electrical conductivity. 

The taste of every drink can be quantified using the multichannel taste sensor. In other words, quantitative measurements of taste are possible by the sensor more accurately than the sense of humans because the present taste sensor has higher reproducibility, durability and sensitivity. 

The determination of odors in water was addressed previously under the discussion on taste. Odors in air are determined differently. They are quantitatively measured by convening a panel of human evaluators. These evaluators are exposed to odors that have been diluted with odor-free air. The number of dilutions required to bring the odorous air to the minimum level of detectable concentration by the panel is the measure of odor. Thus, if three volumes of odor-free air is required, the odor of the air is three dilutions. It is obvious that if these evaluators are subjected to the odor several times, the results would be suspicious. For accurate results, the evaluators... 

One of the more perplexing problems in the weak base field is the basicities of the nitriles. In view of the importance of acetonitrile as a solvent for nonaqueous titrations it would be interesting to have a quantitative estimate of its basicity. There is indeed such a rich variety of measurements that one may classify acetonitrile as either fairly basic or quite nonbasic according to his taste. By implication the base strengths of the other nitriles are equally in doubt. Perhaps some of the disagreement arises from the extraordinary difficulty of removing traces of water from these compounds, since most of the quantitative measurements that have been made involve indirect procedures with which water might interfere seriously. 

Reactions are taking place around you all the time. It is important tto be aware of your surroundings and understand how humans interact with these surroundings. Your five senses allow you to observe the world in which you live. In the lab, you only use four senses to make observations. Nothing is ever tasted in the lab. Sometimes tools can extend your senses. When you describe the color, odor, or texture of an object, you are making a qualitative observation. Quantitative observations involve measured quantities, such as 15 g or 2.5 L. It is important not to confuse observations and interpretations in the lab. Observations are made using your senses interpretations are proposed explanations that are based on observations. In this lab, you will be making both qualitative and quantitative observations. 

In addition to the classical symptoms of zinc deficiency mentioned above, the following unusual conditions have been reported liver and spleen enlargement, abnormal dark adaptation and abnormalities of taste. Several laboratory procedures for diagnosing zinc deficiency are available. Measurement of zinc levels in plasma is useful in certain cases. Levels of zinc in the red cells and hair may be used for assessment of body zinc status. More accurate and useful parameters are neutrophil zinc determination and quantitative assay of alkaline phosphatase activity in neutrophils. Determination of zinc in 24 h urine may help diagnose deficiency if sickle cell disease, chronic renal disease and liver cirrhosis are ruled out. A metabolic balance study may clearly distinguish zinc-deficient subjects. 

Development of this sensor was based on a concept very different from that of conventional chemical sensors, which selectively detect specific chemical substances such as glucose or urea. However, taste cannot be measured in those terms even if all the chemical substances contained in foodstuffs are measured. Humans do not distinguish each chemical substance, but express the taste in itself the relationship between chemical substances and taste is not clear. It is also not practical to arrange so many chemical sensors with respect to the number of chemical substances, which amounts to over 1000 in one kind of foodstuff. Moreover, there exist interactions between taste substances, such as the synergistic effect or the suppression effect. A taste sensor should measure these effects the intention is not to measure the amount of each chemical substance but to measure the taste itself, and to express it quantitatively. The recently developed sensor satisfies this request. In fact, this sensor could detect the interactions between saltiness and sourness. 

In order to deal with these complex problems all data from the oral Zn studies obtained in patients with taste and smell dysfunction were organized and submitted to compartmental analysis (68,69) with the subsequent development of a model (Figure 1) which accounted for all the data obtained over the entire period of these studies, both prior to and after treatment with exogenous zinc (69). These results, compared in normal volunteers, demonstrated that not only was absorption of zinc significantly impaired in the patients compared with the normal volunteers (Table IV) but also that the rate at which zinc was absorbed was significantly lower in the patients than in the normals (3j5 6 and that their total body level of zinc was lower than in the normals (6 6. By the use of this model it was also possible to specify those conditions which were both necessary and sufficient to identify patients with zinc deficiency (60.69). With these techniques it was possible to identify, by objective criteria, laboratory tests by which patients with subacute zinc deficiency could be defined quantitatively. It was also possible to measure various tissue and total body zinc levels and to compare patients with normals so that patients with zinc deficiency could be identified. The major problems presented with these techniques are that they are time consuming, cumbersome, expensive and are presently unavailable in many areas of the U.S. 

Data are presented dealing with a zinc model by which total body zinc mass and other parameters of zinc metabolism can be measured quantitatively such that patients with subacute zinc deficiency can be differentiated from normals by a series of laboratory tests, albeit cumbersome and expensive. The major symptom complex of subacute zinc deficiency is related to taste and smell dysfunction and these symptoms are discussed relative to the body distribution of zinc and the dysfunctions of zinc deficiency. Possible mechanisms by which zinc corrects the deficiency are discussed. These results present a new approach to the diagnosis and treatment of zinc deficiency and help to explain the manner by which these syndromes occur, can be diagnosed and treated. 

The numerical value of taste (or odor to be discussed below) is quantitatively determined by measuring a volume of the sample A (in mL) and diluting it with a volume B (in mL) of distilled water so that the taste (or odor) of the resulting mixture is just barely detectable at a total mixture volume of 200 mL. The unit of taste (or odor) is then expressed in terms of a threshold number as follows ... 

Measurement Systems Analysis starts with translating customer and process requirements into metrics (measurable outcomes). These metrics can be based on subjective qualitative data (taste, appearance, etc.), or objective quantitative data (e.g., seconds, number of defects). The type of data determines the type of MSA ... 

Bottle choice. A widely used method for quantitatively monitoring rodent behavior with regard to taste is the bottle-choice assay. An animal is placed in a cage with two water bottles, one of which contains a potential tastant. After a fixed period of time (24-48 hours), the amount of water remaining in each bottle is measured. Suppose that much less water remains in the bottle with the tastant after 48 hours. Do you suspect the tastant to be sweet or bitter ... 

Funasaki, N. Kawaguchi, R. Ishikawa, S. Hada, S. Neya, S. Katsu, T. Quantitative estimation of the bitter taste intensity of oxyphenonium bromide reduced by cyclodextrins from electromotive force measurements. Anal. Chem. 1999, 71 (9), 1733-1736. 

Flavor is the complex effect of three components taste, odor, and feeling factors. It is usually associated with the pleasure of savoring food or beverages and has, subsequently, suffered from considerable imprecision in definition. Flavor is a sensation with multidimensional components involving subjective and objective perceptions. The sensory perceptions are both qualitative as well as quantitative and, therefore, can be measured. Webster s New Collegiate Dictionary defines flavor as the ... quality of something that affects the sense of taste,. .. the blend of taste and smell sensations evoked by a substance in the mouth. This definition is correct, but incomplete, and should be redefined to include feeling factors. 

It is easy to see how monoculture and attention to quantitative yields would fit most comfortably within this paradigm. Monoculture eliminates all other cultivars that might complicate the design, while concern with quantitative yields avoids the thorny measurement problems that would arise if a particular quality or taste were the objective. The science of forestry is easiest when one is interested only in the commercial wood from a single species of tree. The science of agriculture is easiest when it is a question of the most efficient way of getting as many bushels as possible of one hybrid of maize from a "normalized acre. 

A semi-quantitative structure-taste relationship has been derived97 and extended98 for carbosulphamates using Corey-Pauling-Koltun (CPK) space-filling models for measurements of parameters. Structure-taste relationships for heterosulphamates were developed... 

All respirators that rely on a mask-to-face seal need to be annually checked with either qualitative or quantitative methods to determine whether the mask provides an acceptable fit to a wearer. The qualitative fit test procedures rely on a subjective sensation (taste, irritation, smell) of the respirator wearer to a particular test agent while the quantitative use measuring instruments to measure face-seal leakage. The relative workplace exposure level determines what constitutes an acceptable fit and which fit test procedure is required. 

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