The infusion fermented

What it tells you

That the botanical brought water and fermentable material with it and that nothing stopped the organisms using them. In a properly acidified product this should not happen, so it is a question about the batch and the method rather than about one bottle.

Pressure is a handling issue in its own right

A fermenting bottle builds pressure behind a closure that was not designed for it. Open one carefully if you open it at all, and do not taste it. Nothing you learn from tasting is worth what you risk in a product class with a botulism hazard attached.

Go to the records, not to the bottle

Which acidification solution, what ratio, how long the soak, who carried it out and on what date. If the answer to any of those is unclear for that batch, you have found the problem and the scope of it is the batch rather than the complaint.

Treat the whole batch as suspect

Signs appear at different times in different bottles depending on how much material each one got and where it was stored. A single fermenting bottle is a sample from a batch, not an outlier within one.

The absence of this sign proves nothing

Worth stating plainly, because it is the dangerous inference. The organism this whole section is about does not announce itself with bubbles, a smell or a taste. A quiet, clear, normal-looking bottle from a batch whose control was not applied is not evidence that the control was unnecessary.

Decide what you tell customers before you need to

Write the response while nothing is wrong: what you say, what you ask for, what you replace and how you reach people who bought the batch. A policy written calmly is better than one improvised on the day, and in this product class the day is one where being slow and vague is expensive.

References