Sensory descriptor
Corked
The damp-cardboard mustiness of TCA from a contaminated cork, affecting single bottles rather than batches.
Also called Cork taint, TCA.
- Aroma family
- Earthy
- Does it indicate a fault?
- It depends on the style it is met in
What causes it
2,4,6-trichloroanisole is formed when fungi in cork bark methylate chlorophenols, themselves usually residues of chlorine-based bleaching or of treated timber in a store. Its odour threshold is a few nanograms per litre, among the lowest of any compound in food and drink, and its effect is twofold: at higher levels it smells of damp cardboard and wet cellar, and at levels below its own detection threshold it suppresses the perception of fruit aroma, so a mildly affected bottle simply seems mute rather than faulty. The related compound TBA arises from brominated rather than chlorinated precursors and can contaminate an entire cellar.
There is no acceptable level, and the most damaging levels are the ones below conscious detection, where the bottle is judged as a dull example of the cider rather than as a faulty one.
What raises it
Processes that increase this character, or preserve it where it would otherwise be lost.
Closure selection
Choosing between cork, crown, screwcap, cage and swing-top, a decision that fixes how much oxygen reaches the cider, whether it can hold pressure, and which faults it is exposed to.
Bottling
Transferring finished cider into glass, where the dominant variable is how much oxygen the liquid picks up in the few seconds it takes to fill and close each bottle.
Cellar storage
Holding packaged cider in conditions that let it change slowly and predictably, where stability of temperature matters more than the temperature itself.
Sanitation
The cleaning and sanitising discipline that underlies every other process, and why removing soil must come before any attempt to kill organisms.
The fault it points at
Meeting this descriptor above a certain intensity is how the fault below is usually noticed first.
Fault
A damp-cardboard, wet-newspaper mustiness from trichloroanisole, usually carried by a natural cork but capable of reaching cider by other routes.
Where it is usually met
Fruit and styles this character is recorded in. A record here is where the descriptor is commonly found, not a claim that every example shows it.
About Corked
Cork taint matters in cider chiefly in the bottle-fermented and traditional-method categories, where natural cork remains standard. It is a closure fault rather than a cider fault, and a producer meets it as a random loss across a batch rather than as a systematic problem.
The single most useful diagnostic is variation between bottles from the same batch: mould taint from fruit affects all of them, cork taint affects some.
Others in the earthy family
Farmyard, wet stone, damp cellar, mushroom.
Farmyard
The composite animal-and-straw note of volatile phenols with short-chain fatty acids, central to traditional farmhouse character.
Musty
A stale, mouldy, damp-loft note from fungal metabolites on the fruit or in storage, recorded as a taint.
Damp cellar
A cool, musty, faintly fungal note from moulds and film organisms in the maturation environment.
Mushroom
A distinctly fungal note from 1-octen-3-ol, produced by moulds on the fruit or by film yeast on the surface.
Wet stone
A cool, damp, faintly mineral impression, in cider a product of low-level sulphur compounds and high acidity rather than of minerals.
Forest floor
Damp leaf, soil and fungal character in aged cider, from the combination of oxidised phenolics with low-level fungal volatiles.
What people ask next
Questions readers ask about the things this page mentions. Each one goes to the section that answers it rather than to a page written to receive the question.
- How do i sterilise cider bottles — Wash them clean first, then sanitise with a no-rinse sanitiser or a sulphite solution, and fill while still wet with it. Bottles that look clean but have dried deposits inside are the usual source of bottle spoilage.
- How should i store cider — Cool, dark and at a steady temperature. Light causes light-strike in clear glass, warmth accelerates oxidation, and temperature swings push cider past the closure of a bottle that is not tightly sealed.
- How do you pour bottle conditioned cider — Stand the bottle upright for a day, chill it, and pour in one continuous movement, stopping when the sediment reaches the shoulder. Some traditions deliberately rouse the sediment instead, and both are defensible.
- What is sidra natural — Sidra natural is the still, dry, unfiltered cider of Asturias and the Basque Country, bottled without added carbonation and poured from a height to rouse it. It is tart, funky and made to be drunk in small measures poured one at a time.
- Can i use screw top bottles for cider — For still cider, yes. For anything carbonated, a reused screw-top wine or juice bottle is not designed to hold pressure and should not be used.
- How is cider bottled
Where to go next
- The sensory model — The thirteen structural dimensions and the twenty aroma families, in full.
- Compounds — The chemistry behind the words.
- Troubleshooting — When a perception turns out to be a problem, this is where it is diagnosed.
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 Science of Cidermaking and associated technical writing
Andrew Lea · reference work · passage verified 2026-08-24
Written by a food chemist who worked at Long Ashton on apple phenolics. Unusual among specialist cider writing in that it is primary-research-adjacent: the author is describing work he did, and cites the literature. This is why it is registered at tier 1 for chemistry while a general cider book is not.
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.