I come from an Italian family and know how easily tomato sauce can stain our clothing! To rid this, the best way is to remove any excess food, then flush the stain through and through with cold water. No scrubbing! If this happens while you are out, when you return home soak the stained area in a bowl filled with equal parts of water and 3% hydrogen peroxide for about a half an hour. Rinse with cool water then wash as usual.