Sunday, November 16, 2008

Of Rotten Eggs and Burnt Toast

So our Pinot smells stinky; and not in that cool natural wine stinky smelling way. We have a bit of hydrogen sulfide (H2S) in our wine which smells like "morning breeze" or rotten eggs. Most likely created when the cap in the puncheons got too big and heated up. The 2-foot cap had a higher temp than the must and the yeast in the cap got over stressed. Apparently this happens with Pinot Noir and we now realized we should have gone with 3 puncheons or controlled the cap and temp more during fermentation.
There is no "damage" per se. Just an odor. After some research and soul searching we decided to use a small amount of copper sulfate to convert the H2S into copper sulfide which will percipitate out. I took 3 semesters of chemistry in college and surpisingly I can following what is happening. After some bench testing we agreed that we'd use a 0.1 ppm addition. The plan is to do another test next week to see if we need anything more. There should be no trace of copper in our final wine; however, it is a bit annoying dealing with this issue.

The following is a quick moving of the addition and a small sample of Aaron's dance moves...


davy said...

Does the hydrogen sulfide come from anaerobic bacteria because the yeasts get depressed and don't want to work?

dan-O said...

i think our copper bailout plan is working.