The National Foundation for Celiac Awareness addressed two concerns for those that need to avoid eating gluten, a protein found in wheat, barley and rye.
There is some confusion about vinegar and gluten avoidance. For those with celiac disease or gluten sensitivity distilled vinegar is OK and can be used. The vinegar distillation process breaks down and eliminates any gluten protein fragments. If you are still concerned, rice, apple cider and wine vinegars are gluten-free. Malt vinegar, made by fermenting barley, should be avoided
Though oats are gluten-free, oat crops are often rotated with barley. Leftover barley kernels may contaminate the oat crop. To be sure that oats are gluten-free be sure the oats you use are from a certified gluten-free source.