Sensory descriptor
Damp cellar
A cool, musty, faintly fungal note from moulds and film organisms in the maturation environment.
Also called Cellar, Damp.
- Aroma family
- Earthy
- Does it indicate a fault?
- It depends on the style it is met in
What causes it
Cellars and barrel stores support a fungal and bacterial flora of their own, and the volatiles it produces — chiefly 1-octen-3-ol and 1-octen-3-one from moulds, together with geosmin and 2-methylisoborneol where actinomycetes are present — can transfer into cider both through the air above an open vessel and through barrel staves. It is an environmental rather than a fermentation phenomenon, and it is one of the few cider characteristics attributable directly to a building. Wooden vessels stored in damp conditions carry it most readily.
A faint cellar note is part of the character of cider matured in old wood in a traditional store, and producers working that way generally regard it as inseparable from the method. Where it dominates, or where geosmin is clearly present, it is a mould taint and the cellar rather than the cider is the problem to solve.
The organisms that make it
Where a specific organism is implicated rather than the fruit. Naming one answers a different question from naming a molecule: what is in the cellar, rather than what is in the glass.
Aspergillus species
A large genus of storage moulds, more important in warm climates than in northern cider regions, and a source of musty taint and of mycotoxins other than patulin.
Penicillium expansum
The blue mould of stored apples and the principal producer of patulin, the one genuine chemical safety issue that rotten cider fruit raises.
What raises it
Processes that increase this character, or preserve it where it would otherwise be lost.
Barrel ageing
Holding cider in wood — which may mean an old neutral vat used simply as a vessel, or fresh or spirit-seasoned oak used as a source of flavour, and the two are not the same operation.
Cellar storage
Holding packaged cider in conditions that let it change slowly and predictably, where stability of temperature matters more than the temperature itself.
Fermentation vessels
The container a cider ferments in — wood, stainless, plastic, glass or concrete — and how its permeability, thermal mass and resident microflora shape the result.
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
Musty, earthy, cellar-damp or rotten-fruit character carried in from mouldy fruit or from mouldy equipment, and a marker that the patulin question needs asking.
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 Damp cellar
Damp cellar is the descriptor for what a building contributes, and it is worth separating from the cider’s own microflora because the remedies are different: one is addressed by cleaning and ventilating a room, the other by managing a ferment.
It shades into musty and into corked, and the three are frequently confused. Cellar character is diffuse and affects a whole batch; cork taint affects individual bottles.
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.
Corked
The damp-cardboard mustiness of TCA from a contaminated cork, affecting single bottles rather than batches.
Musty
A stale, mouldy, damp-loft note from fungal metabolites on the fruit or in storage, recorded as a taint.
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.
- What should i ferment cider in — Anything inert, cleanable and closable: glass demijohns, food-grade plastic, stainless steel, or a wooden cask if you can keep it sound. Vessel shape and material change how much oxygen the cider sees and how fast it clears.
- 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.
- Should i ferment cider in an oak barrel — A sound, full barrel is a fine maturation vessel; a leaky, half-empty or previously spoiled one is the fastest route to vinegar. Wood cannot be sterilised, so a barrel carries whatever lived in it before.
- What is a traditional west country cider blend — Predominantly bittersweet fruit for body and tannin, with a proportion of sharp fruit for acidity and sometimes a smaller share of bittersharps for both. The exact composition varied by farm and by what was in the orchard.
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.
Peer-reviewed literature on cider fermentation microbiology
Various journals · peer-reviewed literature · registered as competent for this subject
Covers the microbial succession of spontaneous cider fermentation, the role of non-Saccharomyces yeasts in the early stages, malolactic conversion by Oenococcus and Lactobacillus species, and the organisms behind the principal spoilage faults.
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.