Rotten taste in berry wine

[Ericphotoart]

The last batch of Dragon Blood was fermenting in primary for 10 days. Fruits were in a mash bag and the bag was not tightened, just over the rim of the bucket. It was soaked with wine and exposed to air for those 10 days. I noticed a rotten smell of the wine when I racked to the secondary. Is there anything I can do now? Other batches I did were done with the sack tightened and submerged in wine. I didn’t have this problem with the rotten taste. It is not strong but can be easily noticed.

 

[Rice_Guy]

“Rotten” taste?
* Berries that are exposed to air without mixing can develop mold. (mold requires oxygen) I would say the taste frequently has fruity notes from mold growth. You can’t get rid of mold flavor.
* sewage like would be from part of the ferment doing an anaerobic break down resulting in sulfur compounds/ aromatics and bitter flavor notes. You might be able to deal with sulfur by treating with ascorbic acid and reduless. ,,,,, I will be interested in what others say.

 

[Ericphotoart]

This wine was made in 3 separate buckets and combined in 14.5 gallon carboy. Only 1 bucket was fermented the way it developed a slightly rotten taste. Now how dangerous it is for the whole batch if it is indeed a mold. Can I bottle it safely after some time? What else this mold can create?