<<Disclaimer: Verify this information before applying it to your situation.>>

The following products are gf.  I called each company.

Cook's Pure Premium Quality Vanilla Powder, Fine Bourbon Vanilla, 4.5 oz
Bourbon vanilla is the type of vanilla bean that is used.  Ingredients:
Vanilla bean extractives in a dextrose base (sugar, when I asked the
question).  Cook Flavoring Company 1/800/735-0545

Nature Made -- Calcium and Magnesium with Zinc Mineral Supplement 100
Premium Tablets.  States on the bottle "no chemical solvents, yeast,
starch or gluten" so I called 1/800/276-2878.  I also checked about the
maltodextrin that they use.  It is not manufactured using gluten-based
grains.

Mary in Northern California