Packaging
Bag-in-box
A collapsing laminate bladder in a card outer, the standard farmgate and draught format, which keeps air out during dispense but lets oxygen through the film over weeks.
Also called BIB, bag in box, cider box.
- Stage
- Packaging
- Traditional in
- Somerset, Herefordshire, Gloucestershire
- What it most changes
- Oxidative character up, carbonation down
- Safety
- None recorded
What it is
Bag-in-box packs cider into a flexible multi-layer plastic bladder fitted with a tap, protected by a cardboard outer that carries the labelling. As liquid is drawn, the bag collapses on itself and no air enters to take its place, which is why a box can be served over days without the rapid deterioration of a broached cask. It dominates farmgate sales, cider festivals and much of the British traditional draught trade, and it is the normal format for unpasteurised, unfiltered farmhouse cider. Its limitation is the film itself, which is not an absolute barrier.
Why it is used
- The collapsing bladder means no headspace forms during dispense, so a box can be served from over several days where an open cask of the same cider would already be oxidising badly.
- It is cheap, light, needs no deposit, requires no cellar equipment and no gas, which puts draught cider within reach of farm shops, festivals and small producers with no packaging line.
- It suits live, unfiltered cider that could not be canned or bottled safely, because the bag is not a pressure vessel and any modest gas production simply inflates it rather than building pressure.
How it works
- The bag is a laminate of several polymer layers, typically combining a strong outer film with a sealant inner and sometimes a metallised or barrier layer, and it is filled through the tap fitment with the air expelled beforehand.
- Dispense works by simple gravity with the bag collapsing behind the liquid, so unlike a vented cask there is no continuous air interface at which acetic acid bacteria and film yeasts can colonise.
- Every polymer film has a finite oxygen transmission rate, and a bag presents a large surface area relative to its volume, so oxygen crosses the wall steadily throughout the box’s life whether or not it has been opened.
- The tap fitment and the heat seals are additional ingress points, and the tap is also the one part of the package exposed to handling and to whatever it drips onto once in service.
- Live cider filled into a bag will continue to ferment slowly, and because the bag has no rigid volume the result is a visibly inflated pack and a cider that has gained gas the maker did not intend.
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 |
|---|---|---|
| Oxidative character | Raises | Oxygen permeating the film accumulates over weeks and months even in an unopened box, so oxidative character develops on a fixed schedule set by the packaging rather than by anything the maker does afterwards. |
| Carbonation | Lowers | The pack cannot hold pressure, so dissolved carbon dioxide equilibrates out through the film and the fitment; a cider that went in petillant will be flat well before the film’s barrier life is exhausted. |
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
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.
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.
Acetic acid
The vinegar acid, made by bacteria oxidising ethanol whenever air reaches a cider, and the one fault in cider that no later processing can undo.
Organisms involved
Where it is traditional
The places this step belongs to as a matter of practice. It is not a claim of exclusivity — a method can be traditional in one region and perfectly ordinary in another.
What it is done with
Bag-in-box and canning
Bag-in-box collapses as it empties so no air replaces the cider, which suits still cider dispensed over days; canning excludes light and oxygen completely but depends entirely on a correctly formed double seam and a liner that resists an acidic drink.
Bottling lines and fillers, small and large
Filling is where a finished cider is most exposed: oxygen picked up in the last two minutes can undo a year of care, and carbonated product needs a filler that keeps it under pressure until the closure is on.
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.
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.
Film yeast growth
A pale, powdery or wrinkled film of aerobic yeast growing on the surface of a standing cider, consuming alcohol and acid and producing acetaldehyde.
Unwanted refermentation
Fermentation restarting in a sealed container, generating carbon dioxide that was not planned for and pressure that a bottle may not withstand.
Plastic and packaging taint
Plastic, rubber, adhesive or chemical notes picked up from unsuitable containers, liners, hoses, gaskets or cleaning residues.
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.
Traditional draught cider
Cider dispensed from cask, bag-in-box or gravity without added gas, in the form that British cider has historically been drunk in pubs and at the farm gate.
West Country farmhouse cider
Cider made on the farm from tannic bittersweet fruit, wild-fermented in wood and sold still and unfiltered, in a tradition whose variability is one of its defining features.
Scrumpy
A colloquial West Country word for rough farm cider that has never had a fixed definition and now carries as much marketing weight as descriptive meaning.
Unfiltered cider
Cider packaged without filtration, retaining suspended yeast and fine solids and the body and aroma that come with them.
Still cider
Cider with no perceptible dissolved carbon dioxide, presented as a fermented fruit drink whose texture rests on body, acid and tannin alone.
Still perry
Perry without carbonation, in which the fruit’s sorbitol sweetness and its texture carry a drink that has no bubble to lean on.
More on bag-in-box
The virtue of the format is genuinely mechanical and worth understanding on its own terms. A cask, once broached, admits a volume of air for every volume of cider drawn, so its contents begin oxidising and acetifying from the moment the vent is opened; a bag draws down on itself and admits none. That single difference is why an opened box outlasts an opened cask by a wide margin and why it became the default for farmgate and festival sale of exactly the live, unpasteurised, full-juice ciders the traditional trade is built on. Nothing about it requires gas, refrigeration, cellar cooling or returnable containers, which suits a producer selling from the farm gate rather than into a national account.
Its limitation should be stated as plainly as its virtue. Polymer film is a barrier, not a wall. Oxygen crosses it continuously, the rate depends on the laminate specification and on temperature, and a bag has a great deal of surface area for the volume it holds. Unopened shelf life in this format is therefore short compared with glass or can — a matter of months at ambient temperature rather than years — and the cider inside does not simply hold still and then fail; it drifts, losing fruit character and gaining oxidised, cardboard and eventually acetic notes across its life. Storing boxes cool slows all of this substantially, which is why the cold-chain question matters more here than for any rigid format.
Practically, the failure a customer meets most often is a box kept too long. Farm shops and festival bars turn stock over quickly and the format works; a box bought and left in a warm kitchen for months does not, and the fault is the package rather than the cider. Live cider brings a second consideration, since a bag that has inflated has been fermenting, and while it is not a pressure hazard in the way a bottle is, the tap can spray when opened and the contents will have changed. Producers using the format generally date it conservatively, advise cool storage, and accept that this is a package for cider to be sold and drunk within a defined window rather than kept.
Related processes
Steps that sit alongside this one, replace it, or depend on it having been done.
Packaging
Kegging
Filling cider into a sealed keg for gas dispense or into a vented cask for gravity and handpump service — two formats whose difference is not the container but whether the cider ever meets air.
Packaging
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.
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.
Storage
Shelf-life management
Establishing how long a cider stays acceptable in its package and setting a durability date that reflects evidence rather than convention.
Juice treatment
Sanitation
The cleaning and sanitising discipline that underlies every other process, and why removing soil must come before any attempt to kill organisms.
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 long does cider last — An unopened commercial cider is usually at its finest within a year of packaging, and filtered, pasteurised products carry a stated date. Strong, tannic, bottle-conditioned ciders can improve for several years.
- 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.
- 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.
- 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.
- How much acetic acid is normal in cider — A small amount is present in every cider and contributes lift. Sound Asturian sidra natural has been measured at 0.2 to 0.3 g/L, and a clean modern cider much above about 0.7 g/L is generally showing a fault rather than a style.
- What is oxidation in cider
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.
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.