How come my dishwasher doesn't get tea stains off mugs?

My dishwasher is new-ish. About 3 years old, Kitchenaid, not cheap. It does an OK job with most things, but for some reason, it will not get stains out of mugs used for tea. I’m not talking big horrible stains - if I pull a stained mug out of the dishwasher, it takes a quick wipe of a wet dishrag to get the stains off. No elbow grease, soap, or effort of any type involved.

Other dishes get clean. For example, were I to use a mug for soup and put it in the same spot in the dishwasher, it gets clean.

But tea stains? I might as well hand wash all tea mugs.

What’s going on?

Tea is pretty much a dye. People use varieties of teas to dye things. It’s not as water permeable or soluble as the rest of the junk/gunk in the dishwasher. Giving some light abrasion (scrubbing/wiping/sponge) is what breaks the grip it has on the mugs/cups/whatever.

Why doesn’t the paint on some dishes come off? It’s even tougher than the tea stain, but get some sand paper and take the abrasion to an extreme… it’ll come off. :slight_smile:

Concur: the tea stains are not just sitting on top of the surface like dried-on scrambled eggs, they’ve actually been absorbed by the surface. I’ve got two quart-size Rubbermaid bottles that I’ve used to bring tea to work in almost every day for the past, oh, six months or so, and they are markedly more tea-colored than they were when I started. The two one-gallon pitchers I use to make the tea in, also.

ETA: Hell, even the 8-quart sauce pot I use to brew the tea in is stained, and it’s metal.

I’ve cleaned the inside of a drinks machine before, and let me tell you, tea really stains.

I’ve found that bleach works pretty well for Rubbermaid bottles. Throw a couple tablespoons in the bottle, then fill with warm water. Let it sit for a couple hours, then rinse.

Cleaning the inside of a mug or bottle in a dishwasher can be a crapshoot – the jets have to hit a fairly small area (the opening), so if the object is in at the wrong position the jets can fail to hit some or all of the dirty interior.

Yes. Also, your dishwasher isn’t really a dishwasher, more of a dish sanitizer. Anything that you can get off your plates and glassware with a faucet sprayer, the dishwasher will probably get off. But things that need to be scrubbed off will probably not disappear in the machine - it doesn’t really have that ability.

The idea of drinking bleach residue worries a lot more than stained plastic, but thanks for the tip. :wink:

Bleach is soluble and won’t leave any significant residue, certainly no more than your (already chlorinated) tapwater. There’s no need to worry.

Not true. My dishwasher regularly gets off things that require scrubbing if I do them by hand. But, the dishwasher cycle is long enough to soften up dried on food, and take a look at dishwasher soap some time. It’s rather gritty, and I’m sure it does some of the scrubbing. A plumber once told me to run a spa tub with dish washer soap in it, in order to clean out the pipes for the jets. Yep, it works.

What kind of detergent are you using? I use those cascade complete tablets, and don’t have a problem with tea glasses. Also agree with Tastes of Chocolate, my dishwasher cleans things that would require significant scrubbing.

Modern dishwashers do a lot more than the ones I grew up with. My Father has a brand new one that even has it’s own disposal in it. He can put a pan half full of oatmeal on the bottom rack, and wine glasses on the top rack, and it all comes out looking beautiful.

Have you tried putting tea mugs on the bottom rack? Not a good idea for the rubbermaid bottles mentioned above, but shoudl eb fine for mugs?

An overnight soak with Pepsi has removed coffee/tea stains in my cups. I’ve heard it works really well for cleaning toilet bowls too!

Those little effervescent tablets for cleaning dentures are also a good way to clean off tea stains. (Also for funny-shaped vases you can’t reach into.)

Ooo good tip!

Before I had a dishwasher, many of my mugs and cups had tea stains. I guess I didn’t scrub them enough in the sink. However, since using the dishwasher, I never have stained mugs or cups. They get completely clean.

Dishwashing powder is quite strongly alkaline (pH around 9-10) which is necessary for thorough cleaning. The hydraulic action of the water jets is not going to remove tea or other relatively persistent stains.

This is the part I don’t get. I have tea stains and once in a while I just clean them with a little bleach. It doesn’t make sense that you can simply wipe it off but your dishwasher can’t clean it.

Mean Green is really good at removing tea stains.

That makes two of us. I could see it if it took some elbow grease to clean, but literally, it just takes a wet rag and next to no pressure.

I am inclined to think this may be related to the correct amount of soap in the dispenser, hard water, something like that. Because a true tea stain cannot be wiped off with a wet rag. I think you are dealing with some other kind of residue that correlates to tea.