 How to Remove Mustard Stains from Clothes Hello and welcome to Video Jug. Mustard, like its counterpart ketchup, can produce a vivid stain. You should treat mustard stains similarly to ketchup stains, but there are a few key differences, so pay attention. You will need clear or white dish washing liquid, white vinegar, hydrogen peroxide, glycerin, light-colored cloths, dark colors can lead onto fabrics, and a knife for a spoon. Step 1. Scrape away. Just as with ketchup stains, you will want to scrape away any excess mustard from the fabric. Use a dull knife for spoon and work from the outside inward to avoid spreading the spill. Step 2. Get underneath the stain. When possible, work from the inside out. This helps the stain to lift off of the fabric instead of through the fabric. Fold the light-colored cloth and place it underneath the stain to prevent the stain from spreading to the other side of the shirt. Step 3. Pre-treat. Before throwing it in the laundry, pre-treat the stain with a solution made of clear or white dish washing liquid and lukewarm water, as opposed to cold water with ketchup. Then wash the shirt in the hottest water recommended by the care label. Just don't dry or iron the item until the stain is completely gone. Step 4. Stubborn Stains. If the stain hasn't lifted, try treating it with a mixture of warm water and white vinegar, then washing it again. You can also bleach the stain with hydrogen peroxide, as long as the fabric is color-fast. It's a good idea to test on a hidden area before going to the stain. Step 5. Old Stains. If the stain is older-dried, treat the stain with glycerin and let sit for 30 minutes before trying the other treatments. glycerin is good at loosening the stain and rehydrating it, making it easier to lift. One or a combination of these methods should do the trick. If it doesn't happen right away, don't let mustard get the best of you, some stains just take persistence, so hang in there. Done.