Juice treatment
Juice storage
Holding unfermented juice sound between pressing and fermentation, by chilling, sulphiting, gas blanketing, freezing or aseptic filling.
Also called Holding juice, Aseptic juice storage, Juice preservation.
- Stage
- Juice treatment
- Traditional in
- No single tradition — used wherever it suits
- What it most changes
- Fruit character down
- Safety
- None recorded
What it is
Unfermented apple juice is an unstable material. It is a sugar-rich, mildly acidic, nutrient-bearing liquid at ambient temperature with a substantial wild microflora already in it, and left alone it will begin fermenting within a day or two. Juice storage is the set of practices that hold it in that unfermented state deliberately, for anything from overnight to a full year: refrigeration, sulphiting, blanketing with carbon dioxide or nitrogen, freezing, and sterile filtration into aseptic containers. It exists because the pressing schedule and the fermentation schedule are not the same schedule.
Why it is used
- A press run is governed by when the fruit is fit and when the press and labour are available, while fermentation is governed by vessel space and by when the maker wants the cider; the two rarely coincide.
- Blending at the press requires all the components to be pressed together, so juice from an early cultivar must be held sound until the late fruit is ready.
- Holding juice unfermented allows a producer to ferment through the year at a steady rate rather than committing the entire crop to fermentation in a few autumn weeks.
- Ice cider production depends on holding juice specifically so that it can be concentrated by freezing, which is a storage regime with a purpose attached.
How it works
- Chilling slows everything proportionally — microbial growth, enzymic browning, and the chemical oxidation reactions — without stopping any of them, so refrigerated juice buys days to weeks rather than months.
- Sulphur dioxide binds acetaldehyde and inhibits bacteria and wild yeasts in its molecular form, which is available only at low pH, so a sulphite-based hold is far less effective on a high-pH bittersweet juice than on a sharp one.
- A carbon dioxide or nitrogen blanket displaces air from the headspace, removing the oxygen that drives enzymic browning and that aerobic spoilage organisms such as Acetobacter and film yeasts require.
- Freezing arrests microbial and enzymic activity almost completely and preserves aroma well, but the ice crystals disrupt colloids and the juice may throw a deposit and lose some pectin structure on thawing.
- Sterile filtration into a pre-sterilised aseptic bag removes the organisms rather than inhibiting them, which is the only route to genuine long-term ambient storage but also removes the wild microflora entirely.
What it changes
The direction this step pushes the finished drink in, dimension by dimension. A direction, not a measurement: how far it moves depends on the juice, the temperature and how the step is carried out.
| Dimension | Direction | Why |
|---|---|---|
| Fruit character | Lowers | Even under a gas blanket, esters and aldehydes degrade over time and dissolved oxygen already present continues to react, so held juice arrives at the ferment aromatically flatter than fresh. |
| Oxidative character | Either way | Whether stored juice picks up oxidative character depends entirely on whether oxygen ingress was controlled; a well-blanketed cold hold shows little, a poorly sealed one shows a great deal. |
The chemistry and the organisms
What is actually being changed, and by what. Each entry says what that compound or organism does in cider generally; this page is one place it does it.
Compounds involved
Sulphur dioxide
The antimicrobial and antioxidant on which most modern cidermaking depends, and whose effectiveness collapses as pH rises — which makes every sulphiting decision a pH decision first.
Carbon dioxide
The other product of fermentation, which protects a cider from air while it is being made and, dissolved in the finished drink, changes both its texture and its perceived acidity.
Dissolved oxygen
Essential to a healthy yeast population at the start of fermentation and the principal enemy of a cider from the moment fermentation ends.
Patulin
A mycotoxin produced by the blue mould that rots stored apples, regulated in apple juice worldwide, and the clearest food-safety reason not to press rotten fruit.
Organisms involved
Zygosaccharomyces bailii
A preservative-resistant spoilage yeast that refements sweetened cider and juice, and one of very few organisms able to grow through sorbate and benzoate at cider strength.
Saccharomycodes ludwigii
A large, sulphite-resistant yeast that refements sweet cider in bottle and is one of the classic causes of unwanted secondary fermentation.
Film yeasts
A functional grouping rather than a taxon: the oxidative yeasts that form a skin on cider exposed to air and consume its alcohol and acid.
Acetobacter aceti
An acetic acid bacterium that oxidises ethanol to acetic acid wherever cider meets air, and the organism behind most volatile acidity in cider.
What it is done with
Stainless steel tanks
Stainless steel is inert, effectively impermeable to oxygen, and the only common vessel material that can genuinely be cleaned and sanitised — which is why it displaced wood almost completely in commercial cider making.
Temperature control: glycol, coils and a cold room
Cooling can be applied to the vessel — a glycol jacket or a coil in the liquid — or to the air around it, and for most small producers a cold room, an insulated container or simply a cold building is the cheaper and more reliable answer.
Inert gas: carbon dioxide, nitrogen and argon
Gas is used to push air out of tanks, bottles, kegs and lines, and the three common gases are not interchangeable: carbon dioxide dissolves readily and will carbonate a cider, nitrogen barely dissolves at all, and argon is heavy enough to lie on a surface.
What can go wrong
Faults that begin at this step, or that this step makes more likely. Each one is set out with its causes and whether it can be put right.
Oxidation
The cumulative effect of oxygen on finished cider: fruit aroma flattens, colour deepens towards amber, and a bruised-apple or sherry-like character replaces the fresh one.
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.
Volatile acidity
The measurable fraction of acidity that can be steam-distilled off, dominated by acetic acid and read as vinegar sharpness in the nose and a hard, hot finish.
Acetification
The active conversion of a cider’s ethanol into acetic acid by acetic acid bacteria at an air interface — the process, running in the vessel, that produces volatile acidity.
Ethyl acetate taint
A solvent, nail-varnish or pear-drop aroma from ethyl acetate, the most abundant ester in cider and the one that turns from lift to fault over a narrow range.
Styles it produces
Categories in which this step is characteristic or required. Some name it in their definition; for others it is simply how they have always been made.
Modern mainstream cider
The industrially produced, consistent, carbonated cider that accounts for most of what is sold worldwide, generally made partly from concentrate and finished to a fixed specification.
South African cider
Cider from South Africa, where a very large mainstream category built on Western Cape dessert fruit dominates and a small craft sector works alongside it.
More on juice storage
The reason juice storage exists at all is a scheduling mismatch that no amount of planning removes. Fruit is fit when it is fit; a standard orchard drops its crop over a few weeks; hired press capacity comes when it comes. Fermentation, by contrast, is limited by vessel space and by how much cider the producer wants to have finishing at once. Somewhere between those two the juice has to wait. How long it must wait determines which technique is appropriate, and the techniques are not interchangeable — a chilled tank is fine for a fortnight and useless for a season, while sterile-filtered aseptic storage is capable of a year and completely unavailable to a producer without the equipment.
Each method works by removing a different requirement of the organisms. Cold removes the rate; sulphite removes the tolerance, but only at a pH where the molecular form actually exists, which is exactly the caveat that makes it unreliable for low-acid bittersweet juice; a gas blanket removes the oxygen, which stops browning and stops the aerobic spoilage organisms but does nothing at all about fermentative yeasts, which are perfectly content anaerobically. That last point catches people out: a carbon dioxide blanket on a warm tank of juice prevents oxidation while the juice quietly starts fermenting underneath it. The methods are usually combined for this reason — cold plus sulphite plus a blanket is a far more robust hold than any one of them alone.
Freezing deserves separate mention because it does two jobs. As pure storage it is excellent, holding aroma better than any other method available at small scale, at the cost of freezer capacity and some colloidal disruption on thaw. As a production step it is the basis of cryoconcentration and of Quebec ice cider, where the juice is frozen precisely so that the sugar can be concentrated by drawing off the unfrozen fraction. A maker freezing juice should know which of the two they are doing, since a juice frozen and thawed whole is a storage operation and a juice frozen and fractionated is a concentration one.
The failure modes are mostly about neglected detail. A partially full tank is the classic one: a large headspace of air over juice will give browning and, given warmth, a film yeast or an Acetobacter population on the surface within days. Aseptically filled bags fail at the fitment rather than in the body, so handling and connection discipline matters more than the bag itself. And juice that was already carrying a high microbial load from poor fruit or dirty equipment cannot be stored successfully by any means, because every technique here is a holding action against what is already present rather than a cure for it.
Related processes
Steps that sit alongside this one, replace it, or depend on it having been done.
Juice treatment
Sulphiting
Adding sulphur dioxide to juice to suppress spoilage organisms and oxidative browning, at a level that only means anything once the juice pH is known.
Juice treatment
Juice pasteurisation
Heat treatment of juice before fermentation, which inactivates enzymes and microorganisms, and in doing so removes the wild flora that would otherwise ferment it.
Stabilisation
Sterile filtration
Membrane filtration at a rating that retains viable yeast and bacteria, which is what allows a sweet cider to be shelf-stable without heat or preservative — provided the filling that follows is aseptic.
Concentration and speciality
Ice concentration
Freezing pressed juice and drawing off the unfrozen fraction, so that water is removed as ice and everything else in the juice is left behind more concentrated.
Storage
Cold chain
Keeping an unpasteurised, unfiltered or back-sweetened cider refrigerated from the packaging hall to the point of sale, because refrigeration is the only thing holding it stable.
Juice treatment
Juice blending
Combining juices from different cultivars before fermentation so that the blend ferments as a single batch, as against fermenting separately and blending later.
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.
- Does cider need to be refrigerated — Unopened, no — cool and dark is enough for most cider. Unpasteurised, unfiltered cider keeps far better cold, and anything opened should go in the fridge.
- Why is sulphite added to cider — Sulphur dioxide suppresses spoilage bacteria and wild yeast before fermentation and protects the finished cider from oxidation. How much of it is active depends strongly on pH, which is why low-acid juice is harder to protect.
- Does cider contain sulphites — Most does. Sulphur dioxide is added to protect juice and finished cider, and fermentation itself produces a small amount even when none is added. European labels must declare it above 10 mg per litre.
- Why does my cider taste like vinegar — Acetic acid bacteria have reached the cider and, given air, are converting its alcohol into acetic acid. The cause is almost always oxygen — an unfilled vessel, a leaking bung, or a slow transfer.
- What are carbon dioxide, nitrogen and argon used for in cider making, and how dangerous are they — Air is what damages finished cider, and the cheapest way to remove air is to displace it with a gas that will not react with the cider. That is the whole purpose of inert gas in a cider house.
- What should i know about stainless steel fermentation tanks — A stainless tank is a welded vessel, usually cylindrical, in an austenitic stainless grade chosen for corrosion resistance in acidic, chloride-containing conditions. It contributes nothing to the cider and lets no oxygen in.
Where to go next
- How cider is made — The whole sequence, stage by stage, with the choices open at each one.
- Cider science — The chemistry and microbiology the methods on this page rest on.
- Troubleshooting — What goes wrong, how to recognise it, and whether it can be reversed.
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.
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.