Fault
Excessive sediment
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.
Also called heavy lees, bottle deposit.
- Severity
- Cosmetic — looks wrong, tastes fine
- Where it starts
- Packaging, Fermentation, Carbonation, Stabilisation, Pressing, Storage
- Can it be fixed?
- Yes, if caught in time
- When you notice it
- Maturation, Packaging, Storage
- Signs
- 5 recorded
What it is
Sediment in cider is normal and often desirable — a bottle-conditioned cider must have a yeast deposit, and an unfiltered cider will always throw something. It becomes a fault when there is more than the presentation can carry: a loose, voluminous deposit that will not stay put, that clouds the cider at every pour, and that in a long-stored bottle can begin to contribute autolytic flavours. The judgement is about quantity, compaction and what the cider was meant to be.
What you notice
Grouped by sense, because that is how the fault presents itself rather than how it works.
To look at
- A thick, loose deposit that rises at the slightest movement
- A deposit that occupies a noticeable proportion of the bottle
How the batch behaves
- Cider that cannot be poured clear even carefully, because the deposit will not stay down
- Fresh deposit appearing after packaging in a cider that was not conditioned — That is a different matter and points to refermentation rather than to carry-over.
On the nose
- Yeasty or savoury autolytic notes in a long-stored bottle
The words for it: Lees. Each links to what produces it.
When it appears. In the bottle or the cask, over weeks. A deposit that continues to grow after the first month is worth distinguishing from one that simply formed and stopped.
The useful question is not how much deposit there is but whether it is still increasing, because a static deposit is a packaging decision and a growing one is a microbiological finding.
Andrew Lea, Peter Mitchell / Cider and Perry Academy
What it is mistaken for, and how to tell
One observation per rival, chosen because it separates them rather than because it describes either. Several of these are not faults at all — a style feature, a normal outcome, or the fruit behaving as it does.
- Yeast haze — Settled or suspended. The same material reads as one or the other depending on whether the vessel has been moved.
- Normal bottle-conditioned deposit — Whether the cider was conditioned. A deposit is the expected consequence of a secondary fermentation in the bottle and is not a fault.
- Unwanted refermentation — A growing deposit with rising pressure is a refermentation; a growing deposit without it is not.
- Microbial haze — A spoilage population produces both, and the haze is the earlier sign.
Sediment is expected in bottle-conditioned cider and in anything unfiltered, and pouring around it is a serving skill rather than a workaround. It becomes a fault when the quantity is such that the cider cannot be poured clear at all.
What is actually happening
The chemistry or microbiology behind it. Understanding the mechanism is what makes the prevention make sense rather than being a list of rules.
Cider deposit is a mixture. Yeast cells dominate, along with fruit solids, precipitated phenolic and protein complexes, calcium salts, and any fining agent that was used. Each component settles at a different rate and compacts differently, and a deposit made mostly of fine fruit solids stays loose while one made of flocculent yeast compacts into a firm layer.
Compaction is what separates a manageable deposit from a troublesome one. Well-flocculated yeast forms a dense layer that stays put when the bottle is moved carefully; poorly flocculating yeast and fine colloidal material form a loose sludge that lifts into the cider with any disturbance. Cold storage improves compaction considerably.
Over long periods yeast cells autolyse, breaking down and releasing amino acids, peptides, nucleotides, mannoproteins and fatty acids into the cider. In small amounts this contributes texture and a savoury complexity valued in traditional-method sparkling drinks. In a heavy deposit over a long period it contributes yeasty, meaty and sulphurous notes that most cider does not want.
The commonest cause of an excessive deposit is simply bottling too early — packaging a cider that had not finished settling, so that the settling continues in the bottle where it cannot be racked away.
How it happens
| Cause | Stage | How often |
|---|---|---|
| Bottling before the cider had finished settling in bulk | Packaging | common |
| A poorly flocculating yeast leaving a loose deposit | Fermentation | common |
| Too much priming yeast or too high a priming sugar addition for a conditioned cider | Carbonation | occasional |
| Fining agent that was not fully racked off before packaging | Stabilisation | occasional |
| Fine fruit solids carried through from a hard-pressed or unsettled juice | Pressing | occasional |
| Refermentation in bottle producing fresh deposit after packaging | Storage | occasional |
Can it be put right?
Most cider faults cannot be reversed. Where that is the answer it is given plainly — an honest 'this batch is what it is' is more useful than a procedure that will not work.
| Option | Effectiveness | What it involves |
|---|---|---|
| Store the bottles upright and cold, and pour carefully in one movement | Reliable | The practical answer for a bottled cider. Cold compacts the deposit, upright storage puts it where it can be left behind, and a single steady pour keeps it there. |
| Decant the cider off its deposit before serving | Reliable | Straightforward and effective, at the cost of some carbonation in a sparkling cider. |
| Accept the deposit as part of the style | Reliable | Usually correct. A bottle-conditioned or unfiltered cider is expected to have sediment, and the answer is to tell people to pour it carefully rather than to remove it. |
| Return the batch to bulk, settle and rebottle | Partial | Possible where the batch is worth it. Costs some cider, introduces oxygen and, for a conditioned cider, means starting the conditioning again. |
| Disgorge the bottles | Partial | The traditional-method solution, freezing the neck and expelling the plug of sediment. It is skilled, equipment-dependent work on pressurised bottles and is not a casual undertaking. |
CiderHQ gives no additive dosage figures. An addition is a food-safety decision that depends on legal limits, on the juice in front of you and on what you are protecting against, and the right figure comes from your supplier’s or regulator’s own guidance rather than from a general reference.
Preventing it
- Rack repeatedly in bulk and let the cider settle properly before bottling; deposit removed from a vessel is deposit that is not in the bottle.
- Settle juice before fermentation so fewer fine solids enter the process at all.
- Let the cider get cold before packaging, which compacts the deposit and improves what can be racked off.
- Where a cider is bottle-conditioned, prime accurately and do not add more yeast than the conditioning needs.
- Rack fully off any fining agent, allowing it the full settling time the supplier specifies.
- Store bottles upright for a period before serving so the deposit compacts at the base.
Sediment is the fault entry that most depends on intention. A bottle-conditioned cider without a deposit has failed to condition; the same deposit in a cider sold as bright is a defect. Nothing about the material itself decides which it is.
The useful distinction is between deposit that stays where it is put and deposit that will not. A firm, compacted layer at the base of an upright bottle is a non-problem: it can be poured past and the drinker never meets it. A loose sludge that lifts with any movement makes the cider unpourable, and that is worth addressing.
Almost all of the addressing happens before packaging. Every racking in bulk removes deposit permanently; every settling period the cider is given in a vessel is settling it does not have to do in a bottle. A batch bottled promptly to free up a vessel will do its clearing in the glass instead.
Fresh deposit appearing in bottles that were bright at packaging is a different observation altogether and should not be filed under this fault. That is an organism at work, and the question becomes whether the bottles are gaining pressure.
The compounds involved
Beta-glucan
The bacterial exopolysaccharide behind ropiness, which turns a cider oily and thread-like without changing how it smells or tastes.
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.
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.
Calcium pectate
The gel formed when calcium bridges de-esterified pectin chains, which floats to the surface as the brown cap of a keeve and carries the juice’s nutrients out with it.
Total phenolics
The single number used to summarise everything phenolic in a juice, useful for comparing fruit and misleading whenever it is used to predict how a cider will taste.
The organisms involved
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 bayanus
A name applied both to a hybrid *Saccharomyces* lineage and, loosely, to a whole class of commercial high-alcohol yeasts, and one of the least stable names in fermentation microbiology.
Where in the process it arises
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.
Juice settling
Letting freshly pressed juice stand cold and undisturbed so that gross solids fall, then racking the cleaner juice off the deposit before pitching.
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.
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.
Cold maturation
Holding cider at low temperature so that it settles bright, sheds colloidal material and stops changing microbially, without any additive or treatment being applied.
Lees ageing
Deliberately holding a cider or perry on its fine yeast deposit so that autolysing cells release material that changes texture and foam behaviour.
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.
Faults it is confused with
These present similarly. What separates them is set out on each page.
Yeast haze
Cloudiness from yeast cells that have not settled out, usually because the strain flocculates poorly or the cider has not been left alone long enough.
Unwanted refermentation
Fermentation restarting in a sealed container, generating carbon dioxide that was not planned for and pressure that a bottle may not withstand.
Microbial haze
Cloudiness caused by a growing population of spoilage organisms, and therefore a symptom of something worse rather than a clarity problem in itself.
Pectin haze
A persistent, slightly viscous haze that will not settle, caused by pectin from the fruit remaining in solution as a colloid.
Where this comes up in a guide
The link lands on the step where the fault arises rather than at the top of the pathway, because that is where the decision that causes it is taken.
Carbonation: where the gas comes from and what it costs
How do I carbonate cider, and how do I do it without breaking bottles?
Diagnosing a batch that has gone wrong
Something is wrong with my cider. How do I work out what?
How to taste cider and perry
How do I taste cider properly?
Your first batch of cider
I have apples and no equipment. What do I actually do?
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.
- How do i clear a cloudy cider
- Why did my sweetened cider start fermenting again — Live yeast met the sugar that was added back. Sweetening is only stable if the yeast has been removed by sterile filtration, killed by pasteurisation, or held in check by sorbate together with sufficient sulphite.
- 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.
Where to go next
- The fault finder — Describe what you can smell and see, and narrow it down from the signs.
- All faults — Grouped by where they come from and how serious they are.
- Cider science — The chemistry and microbiology these faults come out of.
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.
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.
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.