Vinegar is a controversial subject in the gluten-free world, so bear with me.
On the one hand, many experts consider almost all types of vinegar including vinegar created from gluten grains to be safe on the gluten-free diet, because the vinegar distillation process breaks down and eliminates the gluten protein fragments.
But other experts question the safety of anything that starts out its life as gluten grains, noting that the available testing technology for gluten doesn't always pick up fragments of the protein that may nonetheless cause people to react.
And finally, you've got people with celiac disease and gluten sensitivity who absolutely, without question, suffer a gluten reaction when they consume vinegar derived from gluten grains, regardless of what either group of experts says.
So Who's Right About Gluten and Vinegar?
Well, really, everyone is.
Vinegar yes, even vinegar from gluten grains tests well below the less than 20 parts per million gluten threshold that is considered "gluten-free" in the United States, Canada, the United Kingdom and Europe. So those who say vinegar is gluten-free are correct ... it qualifies for that distinction based on testing results.
But those who say they react to gluten grain-based vinegar are not imagining their reactions, either. A substantial minority of people with celiac and gluten sensitivity react both to distilled alcohol and distilled vinegar that are originally derived from gluten, even though most experts agree those substances are "gluten-free."
It's not clear what percentage of people this involves there haven't been any studies on it but it's enough that I advise those who are newly diagnosed to proceed very carefully when dealing with those types of alcohol and vinegar until they can determine for themselves whether they react or not.
Learn more about distilled alcohol and the gluten-free diet: Is Alcohol Gluten-Free?
Which Vinegars Are A Potential Problem?
Here's a rundown of the different types of vinegar, and whether each is safe to consume on the gluten-free diet:
- Malt vinegar. This is the only vinegar that everyone agrees is strictly off-limits on the gluten-free diet it's made from barley-based ale that's not distilled, so it definitely contains gluten.
- Distilled white vinegar. White vinegar is the controversial one, as it can be made from almost any starch source or combination of sources, including gluten grains. If you react to distilled alcohol that's crafted from gluten grains, you're at risk for reacting to distilled white vinegar, as well. Proceed with caution.
- Apple cider vinegar. Since this vinegar is based on apple cider, not gluten grains, it should be safe on the gluten-free diet.
- Wine vinegar. Like apple cider vinegar, vinegar made from either red or white wine should be okay to consume.
- Balsamic vinegar. Balsamic vinegar starts out as grapes and is aged in casks made from wood. There's a very small possibility that the paste used to seal those casks (generally wheat or rye flour) could contaminate a batch of balsamic vinegar, but only those most sensitive to trace gluten would notice. Otherwise, balsamic vinegar should be safe on the gluten-free diet.
- Rice vinegar. This type of vinegar commonly used in Japanese cooking is okay for people with celiac or gluten sensitivity to consume as long as it doesn't contain any other types of grains. Be wary of this, though: I had a horrible reaction once from "rice vinegar" I had on a salad at a Japanese restaurant that turned out to also contain barley malt.
- Cane vinegar. Cane vinegar is made from sugar cane, and is considered gluten-free in fact, one small manufacturer of certified gluten-free products uses cane vinegar in a variety of condiments.
- Flavored vinegars. In this case, check the ingredients many of these are safe, but some are not. For example, Heinz Tarragon Vinegar contains barley.
What Else Should I Know About Vinegar?
Here are a few more facts about vinegar and gluten:
- In many countries, malt from barley is used to make most distilled white vinegar, but in the U.S., corn is the most commonly used substance. Heinz, for example, uses corn as the source for its distilled white vinegar.
- When vinegar is used in condiments such as mustard, ketchup and relish, the manufacturer does not need to specify what type of vinegar the condiment contains.
- Similarly, manufacturers do not need to disclose the presence of wheat (one of the top allergens) as a starting ingredient in distilled white vinegar because distillation is considered to break down and remove all the allergenic proteins. Therefore, you can't depend on the label to warn you about wheat-based vinegar you'll need to call the manufacturer to be sure.
- The rice used to make sushi usually contains some vinegar it's generally rice vinegar, but you may want to check the ingredients. (Ever since my bad experience with "rice vinegar" in a Japanese restaurant, I've asked sushi places to make my order with plain rice.)
- A few people who are extremely sensitive to trace gluten seem to react to almost all vinegars, including the ones I listed above as safe. In that case, the culprit could be gluten cross-contamination in the manufacturing facility, or possibly trace gluten contamination in the ingredients used to make the vinegar itself.
The vast majority of people don't need to worry about this, but if you can't seem to find a vinegar that doesn't cause you to react, you might want to try making your own. Here's an article that explains the process: Making Vinegar from Wine.