I have a Tupperware container that held spaghetti sauce sometime in 2024 and has been orange ever since. I kept using it because I was too lazy to deal with it. Every time I pulled it out of the cabinet I would think, “I should really do something about that,” and then I would put leftovers in it anyway.

Last month I finally cracked. Five minutes of effort and that container looks brand new. Here is what actually works on the kind of stains that have been baked in through dozens of dishwasher cycles.

The baking soda paste method (my first try, and it worked)

Make a thick paste with baking soda and a few drops of water — you want it grainy, not runny. Smear it all over the stained areas and let it sit for 15-20 minutes. Then scrub with a damp sponge or, for stubborn spots, a damp paper towel with more baking soda on it.

Baking soda is mildly abrasive so it physically scrapes off the stained layer without scratching the plastic deeply. It also absorbs odors, so bonus: the container stops smelling like last month’s chili.

The sunshine trick (weird but it works)

After scrubbing with baking soda, if there is still a faint orange tint, put the container in direct sunlight for a few hours. UV light naturally breaks down tomato-based stains. I thought my friend was making this up when she told me, but I tried it on a particularly stubborn lid and the last bit of red disappeared.

This works best on clear or translucent plastic. Opaque containers take longer because the light cannot penetrate as well.

The vinegar and water soak

Fill the container with equal parts white vinegar and warm water. Drop in a splash of dish soap too. Let it sit for an hour, or overnight for really bad stains. The vinegar dissolves the oils and acids from tomato sauce and curry that have bonded to the plastic.

Pour it out, scrub with a sponge, rinse. If the stain is still there, repeat but add a tablespoon of baking soda to the vinegar — it will fizz dramatically, which is normal and actually helps lift the stain.

What does not work (save yourself the time)

Dishwasher alone. If the stain has survived even one dishwasher cycle, running it through ten more will do nothing. The heat sometimes sets tomato stains deeper.

Bleach. It might lighten the stain temporarily but it can weaken and pit the plastic over time, and the stain often comes back. Plus your leftovers should not taste like a swimming pool.

Lemon juice alone. It helps with odors and mild discoloration, but it is not strong enough for that deep orange-red that has been there since the Obama administration.