Glossary · Fermentation
Pasteurisation
Definition
Heating cider to destroy yeast and bacteria, either by flash pasteurisation before filling or by tunnel pasteurisation in the sealed container. It stabilises a sweetened product against refermentation.
- Subject
- Fermentation
In more detail
The trade-off is heat character. Excessive or repeated heating produces cooked, jammy notes and accelerates ageing reactions, which is why flash pasteurisation at a short hold time is generally preferred to prolonged in-pack treatment for quality products. Pasteurisation is also what makes shelf-stable sweet cider possible without preservatives.
Where this is covered properly
The glossary defines; these pages explain. Each is described in its own words.
Production
Pasteurisation
Heating cider enough to inactivate the organisms that would spoil it, either in the sealed package or in-line before filling, at a measurable cost in fresh aroma.
Fault
Cooked character
A stewed-apple, caramel or jam-like character from heat applied to juice or cider, most often through pasteurisation or hot storage.
Related terms
Terms that belong to the same part of the subject, or that this one is routinely confused with.
Fermentation
Sterile filtration
Filtration through a membrane fine enough — conventionally 0.45 micron — to remove yeast and most bacteria, allowing a sweetened cider to be packaged without refermenting.
Fermentation
Back-sweetening
Adding sugar, juice or concentrate to a fully fermented cider to reach a target sweetness. Because the added sugar is fermentable, the cider must then be stabilised or kept cold.
Cider
Real cider
A campaigning definition, established by consumer organisations, for cider made from fresh-pressed juice without pasteurisation, carbonation, concentrate or extensive additions.
Law and labelling
Best before
A quality date indicating how long a product remains at its best under stated storage conditions. It is not a safety date, and drinks above a certain strength are exempt from requiring one.
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.
Hochschule Geisenheim University — beverage technology
Hochschule Geisenheim · university · retrieved 2026-08-24
German beverage-technology research covering apple wine and fruit juice processing, including the enzymology of clarification.