The secret to tasting wine like a professional? Spitting

Once in the mouth, the wine is swirled around or chewed for a few seconds. The taster may then make a “duck face” to allow a bit of air in to detect further characteristics, a step called “grumage”.

Next, the mouthful of liquid is spewed back out in an unapologetic burst into a spittoon.

The first step is to identify the wine’s basic quality: is it bitter, sweet, salty, acid or umami — that elusive taste between acid and sweet that is prized in Asia?

The appraisal then turns to the tactile sensation the vintage creates: coarse, astringent, effervescent? Spitting the wine out is intrinsic to a tasting.

Some object to the sight of good wine seemingly going to waste; others fear looking boorish or foolish, or staining their clothes.

Spitting, when the wine mixes with air coming from the nose, can bring out "other prevalent aromatic notes", Pierre-Jules Peyrat says, calling the phenomenon "retro-olfaction".