A postscript:

I gave up on the blackberry wine for a couple of months, fully expecting
to destroy it eventually. But I gave it a sniff recently and found no
trace of the hydrogen sulfide odor present earlier.

I do think the oxygenation helped, but I guess I was too impatient for
results.

Marshall

Marshall Jose wrote:
> Steve Peek wrote:
>> "Marshall Jose" > wrote in message
>> ...
>>> I picked and froze blackberries from a neighbor's plants, and when I
>>> had enough (about 3kg) I prepared my must for the primary. After
>>> crushing the fruit I added the usual things, including 1.5 tsp of
>>> yeast nutrient in the form of food-grade urea. I also sulfited with
>>> two Campden tablets primary must, which by this time was nearly 2
>>> gallons. This sat for 24 hours.
>>>
>>> I then pitched the yeast, Lalvin RC212 (Bourgovin), per their
>>> directions, which involved dissolving some of the yeast in warm water
>>> and letting sit for 15 minutes before adding it to the must. I
>>> noticed at the time that the yeast solution smelled a little
>>> off-putting.
>>>
>>> Within 24 hours of pitching, my must acquired a thick bouquet of
>>> hydrogen sulfide, and 5 days later it's still as bad.
>>>
>>> This happened last year when I made wine from the same plant's
>>> berries., but then I'd used Red Star's Premier Cuvee. I eventually
>>> drove out the H2S with agitation, but it made me wonder what went
>>> wrong. This time I was very attentive to sanitation, and I'm rather
>>> disappointed that the H2S presence has recurred with such vigor.
>>>
>>> After doing some internet searches, I get the impression diammonium
>>> phosphate might have been a better nutrient. Does anybody have other
>>> suggestions? There's still plenty of berries to pick this season, and
>>> I might be able to re-try a batch this season.
>>>
>>> Marshall
>>
>> Give it a good stir with a copper rod. I often have a similar problem
>> with apple wine and the sulphur seems to bind with the copper. It
>> could be your yeast nutrient causing the odor, but some yeasts are
>> known for H2S production.
>> Steve
> I made a "frond" with some 16 ga. copper wire and scoured it, then
> swished it around in the must. Sadly, there was no apparent reaction.
>
> I've since transferred it to the secondary, and I'll be periodically
> oxygenating it using an aquarium pump and a bubble stone until the odor
> is inoffensive.