Fermentation after bottling
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The fact that makes this property different from everything else in the estate: you are selling a container with a live process inside it.
The bottle is a fermenter
A live-cultured drink bottled with residual sugar has everything it needs to keep going: organisms, food and time.
What it does not have is your supervision. The fermentation continues on a shelf, in a van, in a customer's cupboard, at whatever temperature those places happen to be.
And it produces two things as it goes: alcohol, which is the legal threshold, and carbon dioxide, which is pressure.
Both failures come from the same cause, which is why this page sits under the legal section and is read by people worried about exploding bottles.
Three things that decide it
Residual sugar. The fuel. A drier product has less to work with, and a sweeter one has more.
Live organisms. Whether anything is still active, and how much.
Temperature. The rate control, and the only one that changes after the bottle leaves you.
The first two you set. The third you can only influence, which is why it is the one that decides outcomes.
Controlling it
Cold, from filling to the customer. The primary control for a live product, and it has to be genuine: a refrigerated van, a chilled shelf and a customer who knows.
Ferment further before bottling, so less sugar remains and the drink is drier.
Remove or reduce the organisms, by filtration or by heat, which makes the product stable and makes it not a live product, which is a positioning decision as much as a technical one.
Sweeten after stabilizing rather than leaving fermentable sugar with a live culture.
And test the worst case: a bottle held warm for the full shelf life, then measured.
Why this is a packaging page
Because every control above is expressed through the package.
The container has to hold the pressure the remaining fermentation will generate.
The closure has to seal against that pressure and not fail before the bottle does.
The label has to carry the storage instruction, and the distribution has to honor it.
A beverage maker choosing a bottle is choosing how much reaction the package can survive, which is not a question any other property in this estate has to ask.