New winemaker has campden tablet question!

[daveofnorway]

Im making my first wine using a locally made wine kit from a local wine store here in Norway. Im wondering about adding campden tablets. Ive followed the kit instructions (which are in Norwegian!) So far chemical wise ive added potassium metabisulfite E202 and Sulfur E244 as a fermentation stopper.
Then I added abit later what they roughly describe as a clearing mix, it has sat so far in this state for 4 days so far. Apart from yeast at the start nothing more is to be added by this kits instructions. The kit is a red wine and came with about 2L of juice. Tommorow I need to rack this into another container and let it sit for a further 5-6 days for it to be fully cleared. So in total less than two weeks of clearing time. Then it gets bottled. My feeling is that I should add some campden tablets to this. Any thoughts?

 

[DoctorCAD]

Campden is potassium metabisulfate pressed into a tablet, so you already added it.

If you plan on keeping the wine longer than a year, add one crushed tablet per gallon before bottling. It acts as an anti-oxidant.

 

[mdbrewer1]

I have my very first kit in my basement and this has been a question I've been researching myself. It sounds like there really isn't a universal answer since each wine has different levels of "free" SO2, which is what acts as an anti-oxidant and also protects against microbes.

Here is an article I found recently that discusses the sulfite question.

The short answer is that you need to test your wine in order to know the right amount of campden/sulfite to add. The article states that wine should be in the 25-50 mg/L range. If you wine already has high levels of free SO2, adding an entire tablet per gallon will be too much and may give your wine a sulfur taste or smell. From the article...

A minimum free SO2 concentration should always be present to effectively protect wine, but without exceeding prescribed nominal levels. You should have enough sulfite to protect the wine from microbial spoilage but not so much that it can be detected when drinking it. The taste or smell of sulfite is considered a serious wine fault.

Outside of testing both the free SO2 concentration and pH of your wine, it will hard to give you a firm answer. Here is a calculator that can be used if you are able to measure those variables.

 

[DoctorCAD]

1 tablet per gallon at bottling is a standard "rule-of-thumb" that gives the average home wine maker a pretty good amount of free SO2 for protection.

Short of buying a $300 tester, this works just fine.

 

[mdbrewer1]

1 tablet per gallon at bottling is a standard "rule-of-thumb" that gives the average home wine maker a pretty good amount of free SO2 for protection.

Short of buying a $300 tester, this works just fine.

$40 for a Free SO2 test kit that can do 10 samples. $11.51 for 100 pH test strips. The pH strips are probably not even needed for kits.

I'm glad it's worked fine for you, but for about $5 per batch, one can be much more confident than relying on rule of thumb. Some people are more sensitive to sulfites or to the smell/taste of sulfur, so to me it makes sense to make sure the proper amount is added. One could always go with the rule of thumb and hope for the best. If it doesn't work, they would end up needing to buy another wine kit, which would be much more expensive than just buying the testing equipment in the first place.

I probably over-do things, but spending $5 to make sure the $60-$120 kit is treated properly is a good investment in my eyes.

 

[DoctorCAD]

Those test kits are notoriously inaccurate. The pH strips are useless for red wines. I have testing products and the "1 per gallon" tests out very well every time, maybe not to the exact ppm that is targeted, but never so far off that it causes any concerns.

Whatever, I was only trying to answer a simple question to a beginner...

 

[daveofnorway]

Thanks for the info, much appreciated