Sensory descriptor
Lees
A cloudy, faintly bitter, sedimentary character from yeast and fruit solids carried into the glass.
Also called Sediment, Muddy.
- Aroma family
- Fermentation-derived
- Does it indicate a fault?
- It depends on the style it is met in
What causes it
Lees are the settled solids of a fermentation: dead and dying yeast, fruit pulp fragments, precipitated pectin and tannin-protein complexes. Where they are disturbed into the glass, they contribute a dull, slightly bitter, faintly savoury character quite different from the clean autolytic notes of controlled lees ageing, together with a texture that dulls carbonation. In bottle-conditioned cider the sediment is a designed part of the product and pouring technique determines whether it reaches the glass; in a still filtered cider its presence indicates a stability failure.
A light deposit is normal and expected in unfiltered and bottle-conditioned cider and is not a fault. A heavy, easily disturbed deposit that clouds the glass on any normal pour is recorded as excessive sediment.
The compounds responsible
Where the molecule is established. Some descriptors in this lexicon name a compound the compound register does not yet hold a record for; those are named in the cause above instead.
Tannin–protein complexes
What astringency physically is: long tannin chains cross-linking salivary proteins and precipitating them, which is also the mechanism behind fining, protein haze and the classic cider-and-cheese pairing.
Beta-glucan
The bacterial exopolysaccharide behind ropiness, which turns a cider oily and thread-like without changing how it smells or tastes.
Pectin
The structural polysaccharide of fruit cell walls, which decides how much juice a press releases, whether a cider ever clears, and whether keeving is possible at all.
Amino acids
The largest usable nitrogen fraction in apple juice, and the raw material from which yeast builds both its own protein and most of the aroma compounds a cider carries.
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.
Saccharomyces cerevisiae
The yeast that finishes essentially every cider, whether it arrives in a sachet or from the fruit, the press and the vessel.
Saccharomyces uvarum
A cold-tolerant relative of *S. cerevisiae* recovered from spontaneous cider and wine ferments, associated with low-temperature fermentation and higher glycerol.
What raises it
Processes that increase this character, or preserve it where it would otherwise be lost.
Racking
Moving cider off the sediment it has thrown, which both cleans the liquid and — by taking yeast and nitrogen away with the deposit — slows what is left of the ferment.
Fining
Adding a reactive agent that binds a target colloid and carries it to the bottom, chosen according to whether the problem is tannin, protein or a phenolic taste fault.
Filtration
Passing cider through a porous medium to reach a stated visual brightness, at a real cost in colloidal material, body and aroma.
Bottle conditioning
Carbonating cider by letting a second fermentation finish inside the sealed bottle, so the gas is generated where it is going to stay.
Centrifugation
Separating solids from cider by density in a rapidly spinning bowl, continuously and without a filter medium, at the price of shear and oxygen pick-up.
The fault it points at
Meeting this descriptor above a certain intensity is how the fault below is usually noticed first.
Fault
More deposit in the bottle or vessel than the presentation intends, ranging from a normal conditioning yeast layer to a loose sludge that clouds every pour.
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 Lees
Lees character is one of the places where category expectation does most of the work, and the same visual and sensory observation is a feature of one product and a failure in another.
It is distinguished from the desirable autolytic notes by its dullness: controlled lees ageing gives savoury depth without turbidity, whereas disturbed lees give turbidity and take clarity of flavour away.
Others in the fermentation-derived family
Solvent, nail varnish, bread, yeast, cider-shop.
Nail varnish
The sharp solvent lift of ethyl acetate above threshold, the commonest volatile fault-adjacent note in cider.
Bread dough
A raw, yeasty, faintly sour note from live yeast in suspension, characteristic of unfiltered and bottle-conditioned cider.
Solvent
A general chemical, thinner-like impression from ethyl acetate and higher alcohols together.
Cider shop
The characteristic smell of a working cider house — ferment, wood, fruit and a trace of acetic lift together.
Fresh yeast
The clean, faintly sulphidic smell of an active yeast population, met in young cider and during fermentation.
Fusel
A hot, heavy, spirituous impression from elevated higher alcohols, felt as warmth as much as smelled.
Yeast extract
A savoury, umami, meaty-broth note from yeast autolysis during extended lees contact.
Fermenting vat
The pungent, CO2-lifted smell of a ferment in full activity, met in very young cider straight from the vessel.
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.
- Is cider vegan — Cider itself is a plant product, but some producers clarify it with animal-derived finings such as gelatine, isinglass or chitosan. Vegan status therefore depends on the fining regime, which is why some ciders are certified and others are not.
- Which yeast ferments cider — Saccharomyces cerevisiae finishes almost every cider fermentation, whether it was pitched or arrived from the press house. In a spontaneous ferment it is not the first organism present, only the one that survives the alcohol it makes.
- How is sparkling cider made
- What is racking in cider making — Racking is siphoning cider off the sediment it has thrown into a clean vessel, leaving the lees behind. It clarifies the cider and, in traditional practice, is also used to slow a ferment by removing yeast with the lees.
- 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 does pectin do in cider — Pectin is the structural polysaccharide that holds fruit cells together. In juice it holds haze in suspension, and it is the molecule keeving depends on: strip its methyl groups and it will gel with calcium and float the nutrients out of the juice.
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.
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.
CAMRA cider and perry standards
Campaign for Real Ale · specialist organisation · retrieved 2026-08-24
Opened on 2026-08-24. Registered for the consumer-campaigning vocabulary — "real cider", "full juice" — which is advocacy language rather than legal definition, and is recorded as such wherever CiderHQ uses it.
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.