Blind wine tasting

Blinded wine tasting is wine tasting undertaken in circumstances in which the tasters are kept unaware of the wines' identities. The blind approach is routine for wine professionals (wine tasters, sommeliers and others) who wish to ensure impartiality in the judgment of the quality of wine during wine competitions or in the evaluation of a sommelier for professional certification. More recently wine scientists (physiologists, psychologists, food chemists and others) have used blinded tastings to explore the objective parameters of the human olfactory system as they apply to the ability of wine drinkers (both wine professionals and ordinary consumers) to identify and characterize the extraordinary variety of compounds that contribute to a wine’s aroma. Similarly, economists specializing in the wine market have utilized the technique in their research. Some blinded trials among wine consumers have indicated that people can find nothing in a wine's aroma or taste to distinguish between ordinary and pricey brands. Some academics, based on blinded wine tastings, have also cast doubt on the ability of professional tasters to judge wines consistently.

Blind tasting, at a minimum, involves denying taster(s) the ability to see the wine label or wine bottle shape. Informal tastings may simply conceal the bottles in a plain paper bag. More exacting competitions or evaluations utilize more stringent procedures, including safeguards against cheating. For example, the wine may be tasted from a black wine glass to mask the color.

A taster's judgment can be prejudiced by knowing details of a wine, such as geographic origin, price, reputation, color, or other considerations.

Scientific research has long demonstrated the power of suggestion in perception as well as the strong effects of expectancies. For example, people expect more expensive wine to have more desirable characteristics than less expensive wine. When given wine that they are falsely told is expensive they virtually always report it as tasting better than the very same wine when they are told that it is inexpensive. French researcher Frédéric Brochet "submitted a mid-range Bordeaux in two different bottles, one labeled as a cheap table wine, the other bearing a grand cru etiquette." Tasters described the supposed grand cru as "woody, complex, and round" and the supposed cheap wine as "short, light, and faulty."

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