Unable to raise free SO2

jkr · May 23, 2014

I'm having a bit of a problem that I haven't run into before and I was hoping to see if anyone out there had any experience with a similar situation.

I have a red wine with a PH of 3.3 and I'm shooting for a free SO2 value of 16 to get a molecular value of 0.5.

Since January I have added a total of 105ppm of SO2 to the wine, 60ppm of which has been added in the past month, across 4 additions after testing at 0ppm free, in preparation for bottling.

I realize that the SO2 will keep binding to an extent before there's any free SO2, however I feel like I should've seen some results by now after adding so much.

I verified my results by sending a sample out to a lab before the two most recent additions and I also verified that my reagents are good by testing another wine I've made and getting results exactly as expected. The method for testing I'm using is aeration oxidation.

Has anyone else added this much without seeing an increase in free SO2? I'm quite afraid of over-sulfiting this wine. Thanks for the responses.

jensmith · May 28, 2014

I'll be no help with this question, but am bumping the thread in case someone with knowlege just missed the post.

I'm one of those weirdoes who uses very little sulfa in my wines....

Sent from my iPod touch using Wine Making

Turock · May 28, 2014

It just doesn't make sense to me unless the testing method is at fault. Is your indicator solution fresh? If you got the kit from Morewine, you can call them and talk with them. They are very good at helping people who are having problems.

whackfol · May 28, 2014

Just searching for a reasonable answer...how are you adding SO2 and is it full strength?

Calamity Cellars · May 28, 2014

Never mind. I didn't fully read your post.

sdelli · Jun 2, 2014

Your ph is so low it should not take much at all to raise the so2 level.... Just a gram of kmeta should make a significant difference! So2....... Could only be a couple things... Test results are off.... Kmeta you are using is bad.... Or... You have some wine that is a little sick and binding it all up.

Ok..... Three things.......

Sam