Magic eraser by Mr Clean, it is the best thing to keep around to cleans things you never thought of to clean to get the satins off.
Besides doing a great job to clean my sink and tub. Even white wall tires it works great.
I used my chopper with carrots. The chopper turned orange from the carrots. The magic took the stain off. Si it works for stains on your plastic that just will not come off after stained.