A brothy solution
Have you ever checked the ingredients of your everyday broths -- chicken, beef, vegetable? I've seen all sorts of things that I know aren't natural, and even items like MSG! And for us cooking for allergy sufferers, you're sure to find dairy, gluten, soy, corn, etc. So, the best answer is simple. Make it yourself. Once a month, I make chicken broth once a month, using a crockpot, a fryer chicken and a few veggies -- carrots, onion, celery, parsley, salt. Set on low and come back 6-8 hours later. I strain this, then chill overnight. Skim fat away the next day and freeze in ice cube trays.