Coffee-stain filter.

May 8, 2006 5:38 PM

How do I get the coffee stain out of the stainless steel carafe?

The inside of the stainles steel carafe that the coffee brews into has a nasty brown stain on it that so far has resisted all efforts to take it off. I wouldn't care except that along with the stain goes the smell of old coffee and it's making fresh-brewed taste bad.

Now, the bad part - the carafe has a narrow neck *and* is quite tall as shown in the link above, so there's no way of getting a hand in there to scrub it and a rag on a stick can't get enough force. Does anyone know of something that will take the gunk out, or at least neutralize the smell? I've already tried vinegar, CLR, dilute ammonia, and letting it sit with stainless-steel cleaner in the bottom. So far, no joy.

posted by Dipsomaniac to Home & Garden (17 answers total)

Crazy - I scraped the hell out of my knuckles doing this exact thing yesterday (trying the rag-on-a-stick method on a stainless steel coffee thermos with an old coffee patch in it).

I would suggest that you do what I'm going to do - get a bottle-brush, or even a (brand new, of course) toilet brush for this job.
posted by sluggo at 5:45 PM on May 8, 2006

Best answer: I use an oxygenated cleanser sold by homebrew stores under the name One-step. All I do it put a teaspoon full in my 0.5 liter thermos, fill it with warm water and let it sit for 30 minutes. When the time is up, pour it out then rinse it out. It works like a charm, and no scraped knuckles. I imagine something like Oxy-clean would work as well.
posted by mollweide at 6:07 PM on May 8, 2006

Best answer: As a homebrewer, I use a product called One Step to clean my carboys, hoses and whatnot. I iinvariably have a sinkful of the stuff when I am done. I have found that soaking my stainless steel carafe in the stuff for about an hour removes the stain easily. Good stuff.
It's pretty much the same as Oxy-Clean. You might want to try that if you have access to it. Sodium Percarbonate...mmmm.
posted by Seamus at 6:09 PM on May 8, 2006

My mom uses baking soda + narrow scrubber for this purpose. She cleaned my travel mug months ago and I'm still surprised every time I take off the lid and see it all shiny inside.
posted by librarina at 6:39 PM on May 8, 2006

I use baking soda for the travel mugs. You can't use soap on them as the plastic absorbs the soap taste very soon.
I just dump a bunch of baking soda in the mug, soak, and rinse. It kills the taste and smell, and doesn't leave any chemical or soap flavors behind.
posted by deep_cover at 6:59 PM on May 8, 2006

Well, I can tell you what we did for the glass caraffes when I used to work in restaurants and bars -- YMMV on steel. We'd toss in a generous scoop or two of ice, shake in good amount of salt, and squeeze in a little lemon juice, then just... shake 'em and swirl 'em till the stains just sort of melted away. Then we'd turn out the whole dirty ice/lemon/salt sludge, rinse thoroughly, and they were ready to go.
posted by scody at 7:00 PM on May 8, 2006

Oils and suspended very fine coffee solids can easily become trapped in the microscopic finish imperfections common in many kinds of stainless steel, as well as in the joints and lid areas of the carafe assembly. In most cases, you'll need to provide a fair amount of mechanical agitation/abrasion to remove caked buildup, and you want to do this before applying any kind of bleaching cleanser, since the coffee stained deposits are your primary visual indication of where the deposits you are trying to remove are. If you apply a bleaching cleanser too early in your cleaning process, the whitened deposits are hard to see, and you won't remove them, but they will restain easily when fresh coffee is put in, leading to the impression that the carafe is getting dirty faster than it once did, when actually, it just wasn't thoroughly cleaned in the first place. A wadded up Scotchbrite pad, a bottle brush, hot water, and strong detergent is best for this first step. Stuff in the Scotchbrite pad, force it around with the bottle brush, and keep up until you've removed all visible build up lines and the worst of the staining.

Finish with a 2nd wash with automatic dishwasher detergent liquid, which will typically have a high level of chlorine bleach and surfactants, to bleach the remaining discoloration, and remove any rancid coffee smell. Rinsing with hot water, as soon as the carafe is emptied of coffee in use, will remove a lot of oils and fine solids before they dry to cake, and make your cleaning intervals much longer.

Glass lined thermal carafes can be cleaned more easily, and will do a bit better job at keeping coffee warm longer. You wouldn't want to use a Scotchbrite pad on them.
posted by paulsc at 7:09 PM on May 8, 2006

I use a little bit of Clorox in water for this in stainless steel carafes and mugs -- a couple of spoonfuls and fill it up with water.

The stains (and the smell, taste, etc.) will be gone in a very short time (I usually leave it sit an hour or two).

Flush very well with water afterwards, and it should be reasonably safe to drink from (note -- not a guarantee; I'm an amateur chemist at best, do this at your own risk, etc.)

My only other caveat is that I try to be a little careful getting this on rubber/plastic seals and other parts; chlorine is tough on that stuff, and might prematurely age it -- use a good detergent on any non stainless parts.

That being said, I've got several SS mugs and carafes that I've been doing this with for 4 - 5 years now with no noticable bad effects.
posted by nonliteral at 7:14 PM on May 8, 2006

Oops -- should have previewed. What paulsc said.
posted by nonliteral at 7:14 PM on May 8, 2006

Why not use what the professionals use? Urnex will work wonders, and should be available at any local coffee shop that sells brewing equipment. Also available online.
posted by jgee at 7:16 PM on May 8, 2006

Response by poster: I tried our generic oxygenated cleaner (Oxy-prö) and it turned all that brown crap into a suspension of brown crap, which poured out and down the drain. Good call. Now I'm trying the baking soda soak to get rid of the last lingering odour.
posted by Dipsomaniac at 7:17 PM on May 8, 2006

I second Urnex (Cleancaf for me) .. I clean the espresso machine and grinder then soak what needs to be soaked in the not-so-dirty leftover if need be.
posted by kcm at 7:42 PM on May 8, 2006

Dip-It works wonders. I work for a large chain restaurant, and we soak all our coffee pots, coffee mugs, tea urns, and tea pitchers in the stuff weekly, then have them run through the dishwasher (thoroughly washing the stuff off before using anything that's been cleaned with it is a must).
posted by Cricket at 8:43 PM on May 8, 2006

I third Urnex. I work for that big coffee chain and it does wonders for us. Also, I have a stainless steel carafe at home and less than a tablespoon of Urnex brought it from "never been cleaned" condition to "never been used" condition, effortlessly.
posted by dirtdirt at 9:38 PM on May 8, 2006

A fourth for Urnex. I also work for the bux and we use it constantly. It's a godsend.
posted by sara is disenchanted at 10:12 PM on May 8, 2006

Response by poster: As a (probably) final update, I have actually made coffee and it tastes like coffee, not like last week's coffee. I had looked for cleaning products such as Urnex but never saw any around here - the oxy cleaning solution seems to have worked well, however. It's much less bitter and doesn't smell bad today.
posted by Dipsomaniac at 6:57 AM on May 9, 2006

So many responses; can't believe I'm the first with this. The traditional coffee urn cleaner is Cream of Tartar -- it's the only reason I have a bottle on my spice shelf, don't know what else it's good for. (Or maybe that's just for aluminum coffee urns?)
posted by Rash at 9:43 AM on May 9, 2006