CMS Master Sommelier key terms

A fixed sequence for assessing a wine in silence: sight, then nose, then palate, then initial conclusions on condition, intensity, sweetness, acidity, tannin, alcohol, body, flavor, finish, and quality. Using the same order every time keeps judgments comparable across flights.

A structured way to state a wine's quality level by weighing balance, length, intensity, and complexity together. No single factor decides the verdict; a long, complex wine that is unbalanced still rates below a harmonious one.

A tasting discipline that separates a wine's skeleton (acid, tannin, alcohol, body, sweetness) from its aromatic and flavor notes. Structure narrows the identity of grape and place; flavor alone is easily confused by winemaking choices such as oak or lees contact.

The practice of building a conclusion step by step and stating the evidence for each step: observation, then inference, then the narrowed candidate, then the final identification. Examiners reward a defensible chain even when the final call is wrong.

The degree to which a wine expresses the expected character of its declared grape, region, and style. A wine can be excellent yet atypical; in deduction, atypicality is itself a clue pointing to unusual grape choice, site, or technique.

The sensory signature a site imparts through soil, slope, aspect, and mesoclimate, often described as a sense of place. Tasters use it cautiously, because vintage and winemaking can mask or mimic site character.

The year-to-year differences in a wine caused by weather during the growing season and at harvest. In blind tasting, vintage shows up as shifts in ripeness, acidity, alcohol, and the balance between fruit and structure.

Identifying specific wine defects by their sensory markers and, where possible, their cause. Common examples include cork taint (musty, wet cardboard), oxidation (sherry-like aldehydes), volatile acidity (vinegar, nail polish), and reduction (struck match, cabbage).

Aromas and flavors from yeast cells breaking down during extended lees contact, typically bread dough, biscuit, cream, and hazelnut. It is a primary clue for traditional-method sparkling wine and for white wines aged on the lees.

Infection by Botrytis cinerea under humid then dry conditions, which concentrates sugars and acids and adds honey, ginger, and apricot notes. It is the marker of famous sweet wines such as Sauternes and Tokaji Aszu.

The sugar left unfermented in a finished wine, measured in grams per liter. It drives perceived sweetness and body, and its interaction with acidity decides whether a wine tastes dry, off-dry, or luscious.

The sweetness a taster senses, which residual sugar strongly affects but alcohol, glycerol, and fruity esters can also raise. High acidity can make a wine with measurable sugar taste drier than its analysis suggests.

A sparkling wine process in which the second fermentation happens in the bottle, creating pressure and lees contact before disgorgement. It produces fine bubbles and autolytic complexity and is used in Champagne, Cava, and many premium sparkling wines.

The sweetening liquid added after disgorgement to adjust a sparkling wine's final sweetness and balance. Its level determines labeling categories from brut nature to doux and can round out or expose acidity.

Winemaking that limits oxygen exposure, often with inert gas and stainless steel, preserving fresh fruit and sometimes producing struck-match or sulfur notes. A taster uses these notes to infer technique and to distinguish reductive from faulty aromas.

A legally defined wine-growing area whose rules govern permitted grapes, yields, minimum alcohol, and production methods. Knowing these rules lets a taster test a blind hypothesis against what the law allows in a given place.

Hierarchical vineyard classifications, most famously in Burgundy and Champagne, ranking sites by reputation and, in Burgundy, by legal status. In Champagne the terms denote villages and, separately, named vineyard parcels.

A merchant who buys grapes, must, or finished wine and sells it under their own label. The model explains why a single producer's range can span many appellations and why quality varies within one brand.

Champagne made by estates that farm their own grapes, identified by a small producer code on the label, rather than by large houses blending purchased fruit. Style tends to reflect specific villages and parcels.

The French term for grape variety, used on labels and in appellation rules. Knowing a region's permitted cépages is essential when testing a blind identification against legal constraints.

A vineyard planted with several grape varieties intermingled and usually harvested and fermented together. It appears in parts of Portugal, California, and Alsace and complicates deduction because a single-variety guess may fail.

A fractional blending system in which wine moves through a series of barrels over years, blending young wine with older. It is central to Sherry and also used for Madeira and some spirits, producing consistent house styles.

Adding grape spirit to wine to raise alcohol and, when done during fermentation, to stop it and retain sweetness. The timing of fortification defines styles from dry Sherry and Port to sweet Vin Doux Naturel.

Deliberate exposure of wine to oxygen over time, producing nutty, caramel, and dried-fruit notes and often a paler or browner color. It is a defining feature of Oloroso Sherry, Tawny Port, and Madeira.

A dessert wine made from grapes affected by noble rot, concentrated in sugar and acidity with honeyed and spicy aromas. Classic examples come from Sauternes, Tokaj, and parts of Germany and Austria.

Wine made from grapes frozen on the vine and pressed while still frozen, so water stays behind as ice and juice is concentrated. It yields high sugar and high acidity, notably in Germany, Austria, and Canada.

Fermentation of whole grapes in a carbon dioxide atmosphere, producing fruity, low-tannin wines with banana and bubblegum notes. It is associated with Beaujolais and is a clue when tannin is unexpectedly light.

Contact between grape skins and juice during fermentation, extracting color, tannin, and aroma. Its length and temperature shape a red wine's structure and are a standard variable in comparing two wines of the same grape.

Conversion of sharper malic acid to softer lactic acid by bacteria, usually in red wines and some whites. It lowers perceived acidity and adds buttery, creamy notes, which a taster uses to explain texture.

Agitating settled yeast cells in a tank or barrel to increase texture and add bready, creamy complexity. It is common in white Burgundy, Muscadet, and many premium white wines.

A classified growth, as in the 1855 Bordeaux classification or later rankings in regions such as Saint-Émilion. The term signals a legally or historically recognized estate tier and helps a taster rank candidates.

Pouring wine off its sediment into another vessel, or aerating it by that transfer. It is appropriate for older reds with deposit and for young, tannic wines that benefit from air, but not for fragile mature wines.

Solid deposit in a bottle from precipitated tannins, color matter, or tartrates. It is harmless but bitter, so it is separated by careful standing and decanting, especially in older reds and vintage Port.

Harmless crystals of potassium bitartrate that can form in chilled wine. They are not a fault and are usually prevented by cold stabilization; staff should explain this rather than replace a bottle unnecessarily.

The temperature at which a wine is served, chosen to balance aroma release, acidity, and alcohol. Too warm exaggerates alcohol; too cold mutes aroma and tightens tannin, so sparkling and light whites are served colder than reds.

Choosing a glass shape and size to suit the wine and its serving context. A wide bowl suits tannic reds, a narrower one focuses sparkling and delicate whites, and consistent glassware across a flight keeps comparison fair.

A device that draws wine through a hollow needle past a gas blanket without removing the cork. It allows by-the-glass service from expensive bottles while limiting oxidation, though it is not a substitute for proper storage.

The restaurant procedure for handling a suspected faulty bottle: confirm the fault discreetly, show the guest, offer an alternative, and record the bottle for supplier credit. It protects both guest experience and cost control.

The sequence in which wines are served during a tasting, usually light to full, dry to sweet, and young to old. It prevents a heavy or sweet wine from overwhelming the wines that follow.