A tastevin is a small, very shallow silver cup or saucer traditionally used by winemakers and sommeliers when judging the maturity and taste of a wine.
The saucer-like cups were originally created by Burgundian winemakers to enable them to judge the clarity and color of wine that was stored in dim, candle-lit wine cellars. Regular wine glasses were too deep to allow for accurate judging of the wine's color in such faint light. Tastevins are designed with a shiny faceted inner surface. Often, the bottom of the cup is convex in shape. The facets, convex bottom, and the shiny inner surface catch as much available light as possible, reflecting it throughout the wine in the cup, making it possible to see through the wine.
With the advent of modern electric lights, tastevins have very little practical use, although sommeliers often wear them on a ribbon or chain around the neck as a nod to tradition.
Wine cups or tastevins are mentioned occasionally in European inventories from 1200 to 1600, although none are known to exist today. Around 1680, silver cups about 3–4 inches in diameter and 1–2 inches deep came into use in France by affluent people. The custom spread and they came into general use among the wealthy around 1720–1750. They were made by master silversmiths, and were often decorated and engraved with the owner's name. Their size and shape allowed them to be carried in a pocket at all times, and they were prized possessions like rings or watches. Each region in France had its own characteristic style. They were mostly male possessions, but in Normandy about 15 per cent were engraved with women's names.
At that time, wine was sold in barrels and served in pitchers. Wine bottles were very little used before 1800. Diners and guests carried their own knives, and ate with their fingers. Louis XIV refused to use the fork which had become fashionable in Italy, so the use of forks didn't even begin in France until about 1730. One could drink using a wooden or terra cotta cup provided by the host, but carrying your own cup was more sanitary and more distinguished.
After the French Revolution, the general use of these cups died out, but winemakers and traders continued their use. After 1840 the design was mostly standardized, to the type shown in the illustration above. A few tastevins were made and used in countries other than France, but only a few. In the twentieth century sommeliers in upscale restaurants sometimes carried tastevins around their necks with a ribbon or chain, and used them to check wine after opening the bottle. That custom has largely died out, but is occasionally still seen in the twenty-first century.