Look at this pot:
Last night, there was about half a centimeter of very burnt rice stuck to the bottom (I didn’t turn down the heat when the water started boiling…). And it was really stuck. Letting it soak in water in the sink and then rubbing with a sponge, and then scraping with a spatula, got nowhere. Occasionally a black fleck would come off – but at that pace it would have taken years of continuous scrubbing to get it clean.
So, after searching on the internet, I tried several approaches. I boiled water in the pot. I boiled water, ketchup, salt, and baking soda. I boiled just salt and baking soda. I boiled just baking soda. I let the pot full of baking-soda-boiled-water sit for several hours. Finally, things were looking uphill, so I boiled more baking soda and water in the pot and then let it sit overnight. Finally, this morning, with the help of a spatula, I was able to get it clean. Success! I used like half a box of baking soda, though.
This makes sense. We use a more powerful base, potassium hydroxide, in the lab to do something similar. The polymeric organic residues at the bottom of your pot were probably gradually saponified or maybe just dissolved by the hot base. Sodium bicarbonate is not very soluble in water, so the heat probably helped with that, too. Salt should help because it increases the ionic strength of the water, dissolving more bicarbonate. In my family, however, a more traditional approach is to simply soak the pot in water for a day and then scrub the bottom with steel wool. Trying to do some cleaning right after the rice has been boiled seems to help, too.
ReplyDeleteSee, I tried soaking the pot for a little while (like, at least an hour), but it seemed like that alone wasn't going to do much. And I didn't have any steel wool on hand, but I did have a baking soda surplus. And I think by the time I figured out that the rice was totally burned on the bottom it was too late to do any early cleaning.
ReplyDeleteIt was pretty cool when I was boiling ketchup, salt, baking soda, and dishwashing soap (plus water) on high in the pan at once. What it did, basically, was instead of doing little bubbles like boiling water, the whole mixture did one BIG bubble that rose rapidly in the middle of the pan. (I had to keep dumping some out at that point because otherwise I think there would have been an explosion/mess.) Next time I kill a pan I will have to do some more experiments to really optimize my systems.