Had grains going happily for eight months. Switched to coconut sugar about three weeks ago because I had a bag to use up, and now every batch smells like vomit. Rancid butter at best, baby sick at worst.
The grains look normal, not slimy, no fuzz anywhere. Do I throw the grains out and start again, or is this recoverable, and was the sugar really the whole problem?
Do not drink the batch you have and do not use it for a second ferment either. A vomit smell is not an acquired taste.
The grains go in the bin rather than through a reset if you see fuzzy spots of any colour, if they have gone slimy and are falling apart, or if the smell comes back every batch despite the reset. Yours sound salvageable on all three counts.
Also check nothing else changed. Over-fermenting in a warm kitchen or fruit left rotting in the jar does the same thing.
Once they are healthy again, if you still want some mineral content, add it back one variable at a time: a small piece of dried fruit or a very small proportion of unrefined sugar, and keep the rest the same so you know what caused what.
That is the habit worth taking from this. You changed one thing three weeks ago and could name it immediately, which is why the diagnosis took one comment. Change two things and you would still be guessing.
@butyric_acid · last wk. · 3 replies
The sugar was the whole problem and the smell has a name: butyric acid, which is what rancid butter and vomit have in common. Certain bacteria produce it when conditions favour them over the normal yeast and bacteria in the grains, and coconut sugar is one of the commonest triggers people report, along with very dark sugars and molasses.
So something tipped the balance of your culture, and you know exactly what. Plain white sugar is the boring reliable answer.
Reply
Report
@coconut_sugar_swap · last wk.
Grains look fine so I would rather not bin them. What does a reset actually involve?
Reply
Report
@reset_the_grains · last wk.
Pour the liquid away. Rinse the grains gently in cool filtered or dechlorinated water. Wash the jar properly in hot water with no soap residue left. Fresh batch with plain white sugar and filtered water, ferment short, twenty four to forty eight hours, then smell it. Repeat for a few batches until they are themselves again.
Reply
Report