Weber-Fechner’s law

The relationship between the concentration and the perceived taste intensity of MSG was logarithmically linear like those of the four common tastes, although the slope for MSG was somewhat less steep than the others. It means that Weber-Fechner s law holds for all of the five taste substances. The relation of the taste intensity (S) to the concentration (x) can be expressed by... 

Recently Buttery et al. (77) showed the importance of logarithmic values of odor units (log [Uo]) in the evaluation of tomato flavor. The logarithmic factor is correlated to Weber-Fechner s law (72) in regard to odor intensity. Weber-Fechner s law is defined in the following equation ... 

The odor threshold (Tc) was classified by the nomenclatures listed in Table II. The odor-detection threshold (Ted) of each component was determined by the same method previously described (15). First, volatile compounds were dissolved in a small amount of methanol. The solution was diluted by deionized water until the solution was judged as odorless. Because the detection threshold of methanol is very high (more than 100 ppm), it does not interfere with determinations of the thresholds of the aroma components in Citrus sinensis OSBECK, cv Shiroyanagi. Each aqueous solution of volatiles was diluted by a factor of ten. Weber-Fechner s law predicts that the human nose can clearly distinguish only ten fold differences of concentration. We made three series (A, B, C) of diluted solutions to test detection thresholds (A 90 ppm, 9 ppm, 0.9 ppm, and 0.09 ppm. B 60 ppm, 6 ppm, 0.6 ppm and 0.06 ppm, C 30 ppm, 3 ppm, 0.3 ppm and 0.03 ppm). Independently, panel members were... 

Weber—Fechner s law relates the reactions of biological systems to external influences of the environment (light, noise, ionizing radiation, mechanical tension, psychostresses, etc ). 

The perception of added stimulus intensity in the presence of an existing stimulus intensity was the subject of work by Weber, Fechner, and Stevens (Smith, 1998). Weber found that the smallest detectable difference in intensity was a fraction of the intensity already present. This finding has been called Weber s Law, and has been shown to be at least approximately true for stimuli as diverse as light, sound, and the discrimination of heaviness (see Table 6.19.1) for moderate intensities. 

Fechner found that Weber s law is not true for extreme sensations, so he postulated a logarithmic relationship between the sensation felt and the physical stimulus intensity ... 

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