Glassware for cider

Surface area governs how much aroma is evaporating at any moment. A wide bowl exposes more liquid, so more volatile compounds enter the headspace. This is why a tannic, closed cider opens up in a wide glass and stays shut in a narrow one, and why swirling — which coats the walls of the glass with a thin film and briefly multiplies the evaporating surface — has a large and immediate effect.

Rim diameter relative to bowl diameter governs what happens to that vapour next. A rim narrower than the bowl concentrates the headspace and delivers it to the nose in a column. A rim as wide as or wider than the bowl lets the vapour disperse before it arrives. A tumbler is the extreme case of the second: it exposes a lot of surface and then throws away most of what evaporates.

Nucleation governs bubbles in a sparkling cider. Carbon dioxide does not form bubbles spontaneously in clean liquid; it needs a site — a scratch, a fibre, a deliberate etched point at the base of the glass. A perfectly smooth, perfectly clean glass produces few bubbles and can make a well-carbonated cider look flat. A glass dried with a cloth that leaves fibres produces streams of bubbles from the fibre, and a residue of detergent flattens the mousse by disrupting the film that holds bubbles together.

Volume and fill level govern the ratio of headspace to liquid, and how quickly the drink warms. A large glass filled to a third holds a substantial vapour space over a small quantity of liquid, which is what a tasting wants. The same glass filled to the brim has almost no headspace and, if it is being held rather than set down, warms a large volume of cider through the hand.

The Asturian sidra glass — wide, thin-walled, straight-sided and unstemmed — is not shaped to concentrate aroma, and it does not. It is shaped for the long pour: a wide target for a stream of cider falling from a metre or more, thin glass so the cider strikes a hard surface and breaks up, and a straight side so the small measure poured can be drunk immediately before the dissolved gas that the pour raised escapes again. It is a functional shape for a specific technique, and outside that technique it does not do much.

The West Country half-pint or pint glass is a licensing and trade convention. Cider in British pubs is dispensed in the same measures as beer because the law and the trade treat it in the same way, not because a pint glass suits cider.

The Basque sagardo glass, the Normandy bolée — a wide, shallow, handled earthenware cup — and the Hessian Geripptes, the ribbed tumbler used for Apfelwein, are all identity objects as much as drinking vessels. The Geripptes ribbing is generally explained as helping a greasy hand keep hold of the glass. The bolée is opaque, which removes appearance from the assessment altogether. Neither improves aroma, and both are entirely legitimate things to use; they are simply not doing what a tulip does.

Stemware is a handling feature. A stem keeps the hand off the bowl, which slows warming and keeps the glass clean for looking through. It has no aromatic function of its own.

A cider that looks flat in one glass and lively in another is usually reporting on the glass. Detergent residue is the commonest cause: surfactants interfere with the protein and polysaccharide film that stabilises foam, so the head collapses and bubbles do not form streams. A glass that has been washed in a machine with rinse aid and not rinsed again is a frequent offender.

The traditional remedy in beer service — a rinse with cold water immediately before pouring — works for cider for the same reason, and has the additional benefit of cooling the glass. Air-drying rather than towel-drying avoids fibres, which act as nucleation sites and make a cider fizz away faster than it should.

None of this is worth anxiety over a domestic glass of cider. It is worth knowing about when a cider is being judged, because a dirty glass will make an adequately carbonated cider look under-carbonated and can be mistaken for a fault in the drink.