Like mojavean states, the grates are coated with a porcelain enamel, almost a glass like substance. It will wear, and it might be susceptible to attack by "some" of the stronger dishwashing detergents that have potassium or sodium hydroxide in them. I quote one sentence from Wikipedia under the topic 'dishwasher'-"glass dissolves slowly in alkaline aqueous solution."... you can read the article yourself. I mentioned before, it's like the porcelain coating on French cast iron ovens, such as Le Creuset and Staub. Having said that, it would probably take years to have much of an effect. Still, I would rather have the bottom of my pans wear out this coating. The grates will take a seasoning, you just wipe them with the smallest amount of oil, and turn the burner back on. Some oils smoke less than others, refined light olive oil is good, this seasoning may burn off and stick to the bottom of your expensive copper pan, especially if it's a fresh seasoning....otherwise, not a problem, and in fact it probably protects the porcelain from wear. The big thing with cast iron, even porcelain cast iron, is to keep it dry. Sometimes you'll see a light 'bloom' of rust on it, just wipe it off. But if rust gets under the porcelain, it will lift it off and chip it. To clean, I use an almost dry scrubby sponge, and leave the bowls on the cooktop. If I spill a mess of flour, or manage to make a complete mess, I do take the bowls to the sink and rinse them there.

I have cast iron grates (I don't know if you have the same). The manual says for removal of burned on food; place the grates in a covered container or plastic bag. Add 1/4 c ammonia and soak for 30 min. Wash, Rinse and Dry. Maybe this helps???

My grates are black, and when they look a little goey I toss them in the dishwasher. And boy that does the trick they look like new again. I have heard (don't quote me) that this can cause them to rust. I wonder if this would be the case with SS grates. Mine are some black metal, not sure what they are made of. Bosch Range. ~boxerpups This is from Good Housekeeping Magazine Ask Helouise Is there an easy way to keep burners from getting grimy? -- Elizabeth Malvey, Wakefield, MA If you cook, there's really no way around it -- but you can give burners a thorough cleaning. Start by wiping grates and burners with a damp sponge. Remove grates and soak in hot, soapy water for 30 minutes. Add a teaspoon of ammonia to the sink water to help loosen the grime. Scrub them with a stiff brush to remove any remaining gunk. To minimize future messes, keep an eye on pots so they don't boil over.

Some people make their cooktop choice based on performance, not ease of cleaning. We did - we have one in the mid-range - gas burners with more BTUs than a normal household model, a bit less so than a true restaurant model. We're very happy with it. As others have said, cast iron grates can be wiped but really need no cleaning. The burner pans underneath can use attention from time to time, but the best way to keep those clean (on any stove) is to avoid boil-overs. While I haven't tried an induction range, I very much dislike the traditional electric ones. Heat control is too difficult, pan scorching and boil-overs are too common.