Shop bought cherries in kirch fermenting

[Flourpower]

I got my other half a big jar of cherries in kirsch for Christmas. They are mainly in syrup with 5% kirsch. He has eaten about half of them but noticed earlier today that they have started to ferment.

Basically the whole jar is bubbling and the cherries have swelled up. He ate one of the cherries to see what it's like and it's fizzy tasting and very alcoholic. The syrup tastes like extremely strong cider now.

My question is what do we do? Can we rescue them? For eg can we add sugar and make alcohol?

In the meantime we have loosened the lid of the jar to let the Co2 escape.

[MKG]

You're already making alcohol from the sugar in the syrup. The question is, how far will it go? It all depends upon how sugary that syrup is and what the total liquid volume is. At some point (either when the sugar runs out or the liquid becomes too alcoholic for the fermentation to continue), everything will stop. It certainly won't be more than 15% by volume - which is plenty.

Keep your eyes on it, though (or rather, your nose). If it continues to smell OK, then fine. If it begins to smell in any way "wrong" - rotten eggs, overboiled cabbage, that kind of thing - then dump the lot (there are more little beasties than just yeast which can start a fermentation).

Have a look at the label and see if it actually tells you a sugar content. You can then work out probable final alcohol at 1 lb of sugar = 5% alcohol IN ONE GALLON. If you really wanted to experiment then, you can adjust sugar and water content to suit.

Mike