I found this PDF of the judging sheet used by the AHA for judging beer competitions. The definitions are quite interesting, especially the definition of “hoppy” – too often these days I tasted IPAs (both in bottles and at the Japan Craft Beer Festival) which are either just bitter or just sweet. I was beginning to wonder if my definition of “hoppy” was wrong – I’m glad it’s not.

Acetaldehyde — Green applelike aroma; byproduct of fermentation.

Alcoholic — The flavor and aroma of ethanol and higher alcohols. Feels warming.

Astringent — Drying, puckering (like chewing on a grape skin) feeling often associated with tannins.

Cooked Vegetable/Cabbagelike — Aroma and flavor often due to long lag times and wort spoilage bacteria that later are killed by alcohol produced in fermentation.

Diacetyl/Buttery — Described as buttery, butterscotchlike.

DMS (dimethyl sulfide) — A sweet, cornlike aroma/flavor.

Fruity/Estery — Similar to banana, raspberry, pear, apple or strawberry flavor; may include other fruity/estery flavors.

Hoppy — Characteristic odor of the essential oil of hops. Does not include hop bitterness.

Light-struck — Having the characteristic smell of a skunk, caused by exposure to light. Some hops can have a very similar character.

Metallic —Described as tinny, coinlike, or bloodlike.

Oxidized/Stale —Winy, wet cardboardlike, papery, rotten vegetablelike/pineapplelike, sherrylike, baby diaperslike. Often coupled with an increase in sourness, harshness and bitterness.

Phenolic — Can be any one or combination of a medicinal, plasticlike, electrical firelike, listerinelike, chlorinelike, Band-Aid like, smoky, clovelike aroma or flavor.

Salty — Flavor associated with table salt. Sensation experienced on sides of tongue.

Solventlike — Flavor and aromatic character of certain alcohols, often due to high fermentation temperatures, especially in high gravity worts. Like acetone or lacquer thinner aromas.

Sour/Acidic — Pungent aroma, sharpness of taste, like vinegar (acetic acid) or lemon (lactic or citric acid). Sensation experienced on sides of tongue.

Sweet — Basic taste associated with sugar. Sensation experienced on front tip of tongue.

Sulfurlike (H2S; hydrogen sulfide) — Rotten eggs, burningmatches.

Yeasty — Yeastlike aroma and/or flavor.

None of the describe the aftertaste I’ve noticed in some IPAs though – the closest would be oxidized or phenolic but I doubt very much it is either of those.