The ability, odor and taste Perceiving and identifying substances is a complex process involving multiple senses. The six taste sensations sweet. angry. salty. bitter. umami and greasy are above the palate and tongue gustatory perceived. On the other hand, there are around 10,000 different smells (fragrances) that humans can recognize or, if they have the appropriate experience, could. These are over the olfactory mucosa olfactory perceived.
Odor and taste sensations are also supplemented with haptic (tactile) or trigeminal Tactile, temperature and pain information from the oral cavity. These include, for example hot and sharp which accordingly have nothing to do with "smell" older, but have to do with "feel". The impressions received via the tongue, palate and nose mix into an overall impression in the brain, so that the definitive origin can no longer be clearly or unambiguously understood.
It depends on the amount of the smell and taste substances, from when the substance is perceived. This amount is very different depending on the substance. In the case of the substances causing the missing tones in wine, extremely small amounts in the billionth of a gram range are already sufficient (see a table in this regard below wine faults ). This limit is called the perception threshold (limit) and is divided into four threshold values:
The stimulus threshold (also absolute threshold ) describes the sensation of an indefinite smell or taste. That means you smell or taste something, but it is not yet possible to define the substance. The substance is clearly recognized and defined at the detection threshold . With the saturation threshold, a further increase above the detection threshold is no longer possible. The differentiation threshold relevant for comparison tests of, for example, two wines is the difference in concentration, from which a qualitative difference can also be determined.
In the four terms described, the threshold value is the value that is or can be perceived correctly by wine tasters at least 75% under specified conditions. In these, the ability to perceive and identify correctly is strong. That plays with the wine review or quality control play an important role. Specific examples are the award of the Official test number (Germany) and the State test number (Austria). In the food test procedure increasingly used in wine tasting QDA (Quantitative Descriptive Analysis) tests are also carried out on the perception thresholds of the individual examiners.