I can't encourage readers enough to make their own salad dressing. If you keep good olive oil, vinegar, mustard, and lemons on hand you can whip up a small amount of dressing in a couple of minutes. If your dressing contains vinegar and/or citrus like lemon juice...it will store in the fridge safely for a couple of weeks. No preservatives. No cheap oils like store- bought. As Nike says...JUST DO IT!