A wine tasting (also called blind tasting) where either no parameters are known about a wine or only certain parameters are known. The ultimate goal is an objective assessment, where any influence by knowledge of famous names, locations or producers is excluded. The famous British taster Michael Broadbent (1927-2020) believed that the quality assessment of a wine by blind tasting without any information is the most useful educational method for every wine lover, but often the most humiliating one. However, a distinction must be made between blind tasting in the "literal sense" and one in the "figurative sense". Under certain circumstances, however important a wine without cloudiness may be, the "beautiful appearance" of a wine can lead to a distortion of objectivity. In order to generally exclude the influence of colour or optical stimuli, a literal sense can be useful. This can be achieved by tasting under red light, using black tasting glasses, testing in complete darkness or blindfolded. Literally blind tastings are exceptions, however, not the rule.
A blind tasting in the figurative sense, on the other hand, takes place under "normal" light, but without product information. If several wines are compared with each other, common information such as grape variety, vintage or origin can be announced if necessary. In the interests of fair assessment, tasters must never be informed about the producer, brand name or any other data that may point to the producer. The bottles or glasses are identified by number or code for both types. A distinction is made between horizontal tasting or "blind horizontal" (one region, one year, different producers) and vertical tasting or "blind vertical" or also "château vertical" (one winery, but different vintages). The extreme case that no information is known about the wines is rather the exception, but can be a form of examination. If it is known exactly which wines are involved, but not in which carafe they are, one speaks of a half-blind tasting.
In order to exclude manipulations and to guarantee 100% "blindness", the wines must be prepared. Either the labels are removed from the bottles or they are wrapped in tasting covers. The original corks are replaced with neutral pointed corks. Even safer is the more complex decanting into carafes. An unobserved person fills the wines into carafes and identifies them by means of code labels (e.g. numbers), which are not glued on but placed in front of the carafes concerned. A written note is made about this (e.g. No 1 = wine A, 2 = wine B, etc.). The first person leaves the room with the bottles. Now a second person comes and changes the arrangement of the carafes or not. So he changes the carafes or leaves them in the same position. Now the labels are stuck on the bottles, which of course do not correspond to the list of person 1. A note is also made about the exchanges (e.g. 1 with 6, 2 with 4, no exchange with 3 and 5). This means that neither person 1 or 2 nor anyone else knows which wine is where. After tasting, the identity is established by the two notes. See also under wine address and wine evaluation.