People with gluten allergies and intolerances should avoid types of grains that avoid gluten, as well as their byproducts. The vinegar-making process often begins with a gluten-containing grain, but does this necessarily mean people with gluten allergies must avoid vinegar?
People with gluten allergies have difficulty in digesting foods containing gluten. In fact, allergic reactions to gluten will occur in the small intestine and lead to malnutrition. Symptoms of a gluten allergy can include heartburn, constipation, diarrhoea, gassiness and weight loss. If you suspect you have a gluten allergy see your physician so you can be tested. If you do have an allergy, once gluten is removed from your diet your small intestine will heal and you will begin to feel better. However, the change in your diet will need to be permanent--which can be challenging.
Wheat, rye, barley and many other grains all contain gluten. Ingredients made directly from the flour of these grains are obviously off limits. However, gluten can be a hidden ingredient in the form of dextrin, modified food starch, monoglycerides, diglycerides and many ingredients in spice mixes. Thus, any product that is derived from grains containing gluten should be avoided. Many vinegar manufacturers use grain as their base for vinegar (although vinegar can be made from gluten-free starches such as corn or potatoes) which led to the false belief that, since it was derived from gluten, it should be completely avoided. This has since been found to be untrue.
Although the vinegar-making process often begins with a gluten-containing grain, the manufacturing process removes the toxic gluten proteins from the vinegar, rendering it safe to include in a gluten-free diet. Most vinegars--white, apple cider, white wine, red wine and balsamic--are distilled and do not contain gluten and are also safe to consume.
An exception is malt vinegar, which is made from barley and not distilled. Malt vinegar is usually not a component of any other product (e.g., ketchup) but can be used alone as a condiment. Because of its strong flavour it is commonly used on fish and chips. Malt vinegar can also be used during pickling.
Vinegar is a common ingredient in many condiments, including salad dressings, ketchup (and ketchup-based products like baked beans) and mustard. However, these are usually made with distilled vinegar and should be safe for consumption.