Glossary · Faults
Gushing
Also written fobbing. Each is a name for the same thing, which is why none of them has an entry of its own.
Definition
The violent foaming of a cider on opening, so that a substantial part of the contents is lost. It follows over-carbonation, refermentation in pack, or nucleating material in suspension.
- Subject
- Faults
- Also written
- fobbing
In more detail
Over-pressurised bottles are a genuine safety hazard, not merely a nuisance: glass not rated for the pressure can fail. Bottles suspected of refermenting should be chilled thoroughly and opened with care and eye protection.
Where this is covered properly
The glossary defines; these pages explain. Each is described in its own words.
Fault
Gushing
Cider that erupts from the bottle on opening, either because it is over-pressurised or because something in it is nucleating the dissolved gas violently.
Fault
Bottle over-carbonation
More dissolved carbon dioxide in the bottle than intended or than the glass is rated for — a presentation problem at the mild end and a physical hazard at the severe one.
Related terms
Terms that belong to the same part of the subject, or that this one is routinely confused with.
Faults
Unwanted refermentation
Fermentation restarting in a sealed container that was not intended to be conditioned, producing gas, haze, sediment and, in bottles, dangerous pressure.
Fermentation
Priming
Adding a measured quantity of fermentable sugar at bottling or kegging so that a residual yeast population produces carbon dioxide in the sealed container.
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.
Equipment
Crown cap
The pressed metal closure crimped over a bottle lip, lined with a compressible seal. It holds pressure reliably and is the standard closure for bottle-conditioned cider.
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.
Cider and perry production technical training material
Peter Mitchell / Cider and Perry Academy · reference work · registered as competent for this subject
Searched again on 2026-08-25 and it remains the one printed source here that a bibliographic check cannot fix, because it is not a published work with an edition. It is course material issued to participants of a training programme, so there is no catalogue record to verify, no ISBN, and no lawful public copy. Its state stays `registered` for that reason rather than through inattention.
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.