Here's the best tip for dealing with tomato based stains: Never use hot water to treat them. If your first efforts don't get the spot out, don't place a stained, wet garment in your dryer, either. Heat sets tomato stains permanently. Sauces with a tomato base like marinara sauce, ketchup, barbecue sauce, pizza sauce and salsa can all be treated the same way. Try these steps:
- Soak the stain in cold water to which you've added 2 tablespoons of white vinegar and a tablespoon of dishwashing liquid. Soak time is important, so let the mixture work for at least half an hour. Rub the spot to help release any lingering discoloration. Rinse.
- If the stain is still there but lighter, repeat the process above. As long as you haven't applied heat, you still have a good chance of getting the stain out with continued effort.
- If the stain is very noticeable, treat it with a commercial stain remover. There are a number on the market. Follow the manufacturer's directions for presoaking.
When all else fails, you can get more aggressive by using dry cleaning solution. You can also try the DIY approach with WD-40, a spray lubricant you may have in your garage. Test an inconspicuous section of the material first. If you do try WD-40, make sure to remove any oily residue in cold, soapy water after application.