Reaction to potassium metabisulphite

Adam,

It sounds like you got a whiff of sulfur dioxide gas from your solution.

What you went through wasn't an allergic reaction, just a normal reaction to a very irritating substance. Perhaps you breathed in a bit of bisulphite dust, or maybe gas came out of your strong solution, but it's something to be cautious of in the future. Many people prefer to handle their bisulphite only in a well ventilated place. I've had a whiff or two over the years, but it sounds like you had a memorable one.

Good Luck

Adam, I would agree with everything Mike mentioned but would comment on the strength of your solution. It sounded incredibly strong, 1/4 teaspoon in 5 gallons = roughly 50 PPM. It sounds like you mixed up a 1 to 2% solution. I wouldn't take a wiff of that, it's a whole lot of sulfur, it should have taken your breath away.

You can probably use more like 1/4 teaspoon in a quart, but it's actually more effective at lower pH so it's common practice to use some citric acid to drop that.

I use a teaspoon of citric and 1/2 teaspoon K2SO4 in a quart spray bottle as a sanitizer for everything. I do make beer and just spray the caps in a bowl, flip them around and spritz again. I may not be as sensitive to is as you but that seems to work for me.

Joe

Adam - For my beer making I used to soak caps in Iodophor. Then I used Vodka. Finally, now days I don't sanitize them at all but I do keep my fingers away from the inside. And, if they drop on the floor I don't use them. K metabisulfite is probably OK as a sanitizer for beer caps but if you're really concerned I would use Iodophor. AFAIK mine never rusted. Like Joe said be sure to acidify your sanitizing solutions...even the Iodophor. My KC area water is pH 9 and K metabisulfite is worthless at that pH.

Bill Frazier Olathe, Kansas USA

I double checked the packet and it claimed for a sanitizer, I should use

I have a sore throat right now and I'm debating if I actually got sick instead. It was just bad timing. But a whiff of that did burn me up a bit.

Also, this morning when I checked the bowl--I had left it out with two caps in it--the fluid was orange. What is that?

Adam,

My guess is that the acidic solution leached out some iron from the caps, and the iron later oxidized to orange rust. Much the same as some people find in their toilet tanks.

To use metabisulfite for sanitizing it does take a strong solution so there are better sanitizers out there imho. Using it in wine for its antioxidant and antimicrobial properties it is used in much less concentration but still can give you a nasty blast when you're mixing it up.