Glossary · Sensory
Mousse
Also written head, foam. Each is a name for the same thing, which is why none of them has an entry of its own.
Definition
The foam a sparkling cider forms when poured, and its persistence. Fine, long-lasting mousse is associated with bottle conditioning; coarse, quickly collapsing foam with injected gas.
- Subject
- Sensory
- Also written
- head, foam
In more detail
Foam stability depends on surface-active material — proteins, mannoproteins and polysaccharides — as much as on the quantity of gas, which is why heavily fined and filtered ciders can be well carbonated and still foam poorly.
Related terms
Terms that belong to the same part of the subject, or that this one is routinely confused with.
Cider
Sparkling
Carrying enough dissolved carbon dioxide to form a persistent bead and a distinct prickle, whether from bottle conditioning, tank conditioning or injected gas.
Chemistry
Carbon dioxide
The gas produced alongside ethanol in fermentation, and the gas that makes a cider sparkle. Its solubility falls as temperature rises, which is why a warm bottle foams.
Fermentation
Bottle conditioning
Carbonating cider by fermentation inside the sealed bottle, either from primed sugar or from sugar left over from an incomplete ferment. The yeast deposit remains unless the bottle is disgorged.
Serving
Escanciar
The Asturian pour: the bottle held high overhead and the glass low at the hip, so that a thin stream falls a metre or more and breaks on the rim of the tilted glass.
Where to go next
- Cider glossary — The whole vocabulary, by subject and A–Z.
- Comparisons — Terms that are only really clear when set against the thing they are not.
- Search — Finds terms by their aliases and by their spellings in other languages.
Sources
What this page rests on. Where a source is marked as registered rather than read, CiderHQ is recording that the body is authoritative on the subject without claiming to have worked through the document itself. See our evidence policy for what each state means.
The New Cider Maker’s Handbook: A Comprehensive Guide for Craft Producers
Claude Jolicoeur, Chelsea Green Publishing, 2013. ISBN 9781603584739 · reference work · bibliographic record verified, not opened 2026-08-25
Bibliographic record verified on 2026-08-25 against the Open Library union catalogue: Chelsea Green Publishing, 2013, ISBN 9781603584739, one edition recorded. That establishes the citation points at a real book in a stated edition, which is what a citation needs and is all it establishes. No copy was opened and nothing is quoted from it. The book itself is in print and not digitised in any open collection; where CiderHQ needs a figure from this territory it uses an accessible research source instead and says so.
BJCP Beer Style Guidelines — cider and perry categories
Beer Judge Certification Program · classification framework · retrieved 2026-08-24
Opened on 2026-08-24, and the edition matters. CiderHQ registered the 2015 cider guidelines; BJCP has since published a 2025 cider edition, and the old URL now redirects into the current guidelines index. A competition style guide is a dated framework rather than a standing definition, and citing the wrong edition of one is the same class of error as citing a superseded specification. CiderHQ treats BJCP as one competition framework among several and never as the universal cider taxonomy.