What are Campden Tablets?

January 27, 2008 at 5:44 pm (Thoughts, Winemaking, Winemaking Tips) (campden, homemade wine, metabisulfite, sulfites, Winemaking)

Let me start by saying … “Who came up with this?” Okay, I get the idea, it’s the stuff we use to kill wild yeast, but it comes in pill form?!? I find that kind of bizarre and creepy.  This is one totally toxic pill.

Look, Campden tablets are Potassium Metabisulfite, or at least they are supposed to be. Sometimes they are Sodium and not Potassium. Here’s what I recommend. Buy a small jar of Potassium Metabisulfite in powder form. It’s inexpensive ($3) and you can make however much you want at whatever concentration you want.

It’s very hard to control the dosage with a pill, so I make a 2.5% solution by adding 28 grams (approximately 4 teaspons) of powder to one liter of water. I typically make half liter batches, you want the solution to be fresh.  I bought a small jewelers scale on eBay, but you can get them all over the place now for like $12. It’s so much easier to deal with chemicals if you can weigh them accurately.

I have a table that tells me how much of the 2.5% solution to add to get the desired level of sulfites. When I am making my own wine, I will typically add 50 ppm of sulfites to the must.  That means I need 17 ml of 2.5% sulfite solution per gallon, or 100 ml to a 6-gallon batch.  Scale accordingly or email me if you have questions.

I also use the solution in the airlocks.  I once had a problem with mold in the airlock, but that won’t happen if you use the sulfite solution.  Even if the liquid draws back into the wine, it won’t hurt anything.

More on this topic another time.