What's on the bottom of my kettle?

[Eskimo Spy]

I've noticed this after each AG batch, but some PBW in a 30 minute soak has taken it off before. I just finished soaking it for 30 minutes in 2 gallons of hot water with 4 oz. of PBW, and it isn't coming off this time. It's a 40 quart SS kettle.

So first, any idea what it is? Second, would it be better to put 4 oz. in 2 gallons of water and let it soak overnight?

 

[Clonefarmer]

What kind of metal is the kettle?

Doh just saw the SS.

 

[Eskimo Spy]

I am using Ozarka spring water to brew with, I'm not sure if it's minerals from the spring water or not, but FYI.

Also, it really doesn't collect on the sides, just on the bottom of the inside of the kettle.

 

[Clonefarmer]

Could be calcium.

 

[IrregularPulse]

I would scrub real good and try a different water source. I'd say it'd have to be something water related.

 

[Baldy_Beer_Brewery]

Are you sure it is stainless? That looks more like my aluminum kettle than it does my stainless kettle. But I have had that in my pots before and a little scrubbing takes it right off. I still don't know for sure what the hell it is. I've always assumed it was cooked on trub.

 

[enderwig]

Bar Keepers Friend is your friend, wal-mart has it for less than $2 a can.

 

[Wayne1]

What is on the bottom of your kettle is known as beer stone or calcium oxylate.

An alkaline cleaner, such as PBW, will not remove it.

You will need an acid cleaner to get rid of it. A nitric/phosphoric acid blend is what will work best. Five Star makes such a cleaner. They call it Acid 5.

You should get in touch with your LHBS to see if they can order it from Five Star.

Acid 5 should take it off very quickly. If you cannot find it, you can use most acids. Phosphoric alone will work, but it will take longer. Even a long soak with vinegar will remove it.

Remember, alkaline cleaners remove organic material, such as trub, etc. Acids are for inorganic material. Like beer stone.

 

[Eskimo Spy]

Yes, it's stainless, I bought it new about two months ago.

I understand the chemistry, what I didn't know was what I was dealing with.

Star San should be strong enough to remove it, how long of a soak do you think it would take to remove it? Thanks!

 

[Wayne1]

Star San is a sanitizer that uses a small amount of phosphoric acid.

Using it undiluted, with a scrubby, may work. Make sure you wear gloves if you try this.

You can also try an overnight soak.

Typically, a nitric/phosphoric acid blend is used to remove beer stone in commercial breweries. That is what I am most familiar with.

 

[Eskimo Spy]

Since it's such a small amount, I'll try the Star San first. If that fails, I'll get some Acid 5 or something like it. Fortunately, one of my good friends is a chemist, so I'll consult her as well. Thanks a lot!

 

[DeafSmith]

I have some stuff that looks like that at the bottom of mine after each brew. I just pour a little white vinegar in there and rub it around with a sponge for a minute or two, then rinse - it comes right out and the kettle looks like new.

 

[conpewter]

Won't hurt anything to leave it there either.

 

[Eskimo Spy]

The overnight soak using diluted Star San took it off.

 

[Jhenjum]

You can also try a dilute vinegar solution and that will be acidic enough to remove beerstone.

 

[DeafSmith]

You can also try a dilute vinegar solution and that will be acidic enough to remove beerstone.

I don't even dilute it. I put in enough full strength vinegar to just cover the bottom, and as I said in my earlier post, rub it around for a minute or two, then dump it out and rinse thoroughly.

 

[Lil' Sparky]

Bar Keepers Friend. I think it's oxalic acid or something like that. GREAT at cleaning up stainless.

 

[beerthirty]

For light deposits like that I take a lemon off my neighbors tree, cut it in 1/2 and rub the lemon on it. A wipe down with a paper towel and its done. The neighbor still doesn't know.

 

[DeafSmith]

For light deposits like that I take a lemon off my neighbors tree, cut it in 1/2 and rub the lemon on it. A wipe down with a paper towel and its done. The neighbor still doesn't know.

I was just thinking that lemon juice would probably work and would sure smell a lot better than vinegar.

 

[Eskimo Spy]

Good suggestion all, thanks so much for the help. Plus, a lemon is cheaper than anything else I've been using!