SO2 Testing

[homer]

I bought the Midwest SO2 testing kit and I'm starting to wonder how accurate the results are so I tested some "store bought" wine. The 2006 Italian Chianti showed zero, I mean zero, the $2 (actually it was $3 bucks) buck chuck showed about 8-10ppm, some two year old white wine from a local commercial vinter showed less than 10ppm. I don't know what do you make of this? I wish I had some buffer solution to test my SO2 tests. bk

 

[Runningwolf]

Exactly what kit did you buy? Is it a aireation /oxidation kit?

 

[ibglowin]

LOL, yes what is a Midwest SO2 test kit!

 

[homer]

It is the Master Vinter Aeration Oxidation Free SO2 Testing Kit from Midwest Supplies, $99.99

What does LOL mean? bk

 

[Runningwolf]

Ok that test should give you a very accurate reading. I was just wondering if you were using titrets from Hanna.

 

[homer]

I'm going to call Midwest tomorrow and ask why their instructions say to use 3% H2O2 but the Valley Vinter dilutes the H202 to .3%. bk

 

[Gedanken]

I put together my own aeration-oxidation system using several documents on the Internet and the information provided by "The Homebuilt Winery" book. They all list 3% H2O2.

 

[knockabout]

homer: lol = laugh out loud

 

[homer]

Spoke with the Valley Vinter today about his You Tube video on So2 testing, his first question was, am I testing for total So2 or free So2, OK I give, with my testing equipment what am I testing for? bk

 

[captainl]

Huh....I was under the impression you needed to spend several hundred dollars to test so2 levels. I wrote off testing so2 as too expensive but this might change that. Any reviews on accuracy are appreciated.

 

[ibglowin]

Your testing for free SO2 if your test is aeration/oxidation. You can use plain old peroxide from the store. What you need to do is only order small amounts of NaOH as needed 100ml, not 1000ml as it does have a shelf life.

No, you don't have to spend hundreds of $$ to test for SO2. More Wine has one as well for ~$100 same thing aeration/oxidation. This is one of the most accurate test out there but it does have a learning curve. More Wine has some excellent videos as well on You Tube.

 

[SBWs]

Agree with Mike, there is a learning curve. Best to make up a stock solution of a known value and then run some test until you get the right results.

Also good to keep chemicals refrigerated.

 

[Crinton]

Homer - I have the same testing kit and wondered how accurate the results were too. I made up a control solution, targeting 35 ppm and kept getting results 1/2 or 1/3 as high as they should have been. Repeatedly. I couldn't figure out what was off.

Turned out my potassium metabisulfite was old. Once I switched to an unopened pack, I reached 30ppm.

Make sure you refrigerate your hydrogen peroxide and that you don't contaminate your solutions as you reuse pipettes...

 

[homer]

Never thought about storing H2O2 in the ice box, will from now on. One trick I did to stop contamination was label the pipettes and always rinse out the 20ml with the wine I'm testing. bk