The Malting Process: How Barley Becomes Malt (and What That Means for You)

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Malt starts out as ordinary barley. Three controlled steps turn it into malt: soak the grain, let it sprout, then dry it with heat before it can grow into a plant. Maltsters call those steps steeping, germination, and kilning [Barley in the Production of Cereal-Based Products, Plants, 2022].

Almost everything else about malt follows from those three steps. The sprouting is what builds the enzymes. The heat is what stops the sprouting and creates the color and the toasted aroma. And because the grain underneath is barley, the malting process leaves you with an ingredient that contains gluten — the single most important thing to know about malt if you have celiac disease.

Here is how each step works, what malt actually does in your food, and where it is worth being careful.

The three steps of the malting process

1. Steeping

Dry barley is dormant. Steeping wakes it up. The grain is soaked in water until it has taken up enough moisture to begin germinating — a matter of hours, not days.

2. Germination

The wet grain is spread out and allowed to sprout under controlled temperature and humidity. This is the step everything depends on, because a germinating seed builds the tools it needs to feed its own embryo. Chief among them are amylase enzymes, which start cutting the grain’s stored starch into sugar. Germination is deliberately allowed to run until the grain has opened up as much extractable material as possible [Plants, 2022].

Barley is malted more than any other cereal, though wheat, rye and oats can be malted too [Plants, 2022]. If you want the fuller picture of the grain itself, see our guide to barley nutrition and traditional uses.

3. Kilning

Warm air dries the sprouted grain — “green malt” at this stage — which halts germination while leaving the enzymes largely intact. Drying temperature is what gives each malt its identity: pale, crystal, coffee, chocolate and black malts are the same grain taken to progressively higher heat [Plants, 2022]. The dried rootlets are rubbed off afterward, and the finished malt is either milled into flour or extracted with water.

That water extract has a legal definition worth knowing. Malt syrup and malt extract are interchangeable terms for a viscous concentrate of a water extract of germinated barley [FDA, Gluten-Free Food Labeling Final Rule Q&A, 2022].

The forms of malt you will actually run into

Malt reaches your kitchen under several different names, and they are not interchangeable — the difference between an enzyme-active malt and a deactivated one changes what the ingredient is for.

Form of malt	What it is	Where you meet it
Malted barley flour / diastatic malt powder	Milled malt with its enzymes still active	Added in small amounts to bread, bagel, pizza and pretzel doughs as a conditioner
Non-diastatic malt powder or extract	Heated enough to deactivate the enzymes; used for flavor and color	Malted milk powder, malt balls, cereals, cookies, some breads
Malt syrup / malt extract	A thick concentrate of a water extract of germinated barley	Baking, brewing kits, some cereals and snack bars
Malt vinegar	Made by fermenting a barley malt infusion, without distillation	Fish and chips, chips and crisps, marinades, dressings
Malt beverages	Fermented drinks made from malted grain, with or without alcohol	Beer, non-alcoholic beer, malt drinks, malted milkshakes

Diastatic malt flour is added to doughs that need more enzyme activity; non-diastatic malt is used for flavor, color and sweetness, since it carries a significant amount of its own sugar [Plants, 2022].

Is malt actually good for you?

Malt is best understood as a flavor and a sugar, not a health food. That is not a knock on it — it is a genuinely useful baking and brewing ingredient — but the health claims attached to it are weaker than they sound. Here is how the evidence sorts out.

Well established: malt is mostly sugar

The point of malting is converting starch into sugar, so the concentrated products are sugary by design. In the U.S., barley malt syrup used to sweeten a product counts as an added sugar. The Dietary Guidelines for Americans recommend keeping calories from added sugars under 10 percent of your daily total, and the Daily Value used on the Nutrition Facts label is 50 grams a day on a 2,000-calorie diet [FDA, Added Sugars on the Nutrition Facts Label, 2023]. Malt syrup is not meaningfully better for you than other syrups.

Not supported: malt as a digestive aid

Malt has a long reputation as something that “aids digestion,” and you can see where it came from — the grain’s enzymes really do pre-digest starch. But they do that work in the dough or the brewing mash, before you eat it. Your own body already supplies the enzymes that break down starch: saliva contains one, and the pancreas delivers more into the small intestine [NIDDK, Your Digestive System & How It Works]. There is no good clinical evidence that eating malt improves digestion in a healthy adult, and non-diastatic malt — the kind in most foods — has had its enzymes deactivated anyway. Treat this claim as unproven.

Promising but limited: sprouting and nutrients

Germination does change a grain’s nutrition. Barley sprouts have been reported to make more nutrients available than mature grain, including folate, iron, vitamin C, zinc, magnesium and protein [Plants, 2022]. Two caveats keep this from being a reason to eat malt. Sprouts are not the same product as kilned malt or malt syrup, and the quantities of malt in a bagel or a bowl of cereal are small. If you are after the documented benefits of this grain — the cholesterol and blood-sugar effects tied to barley’s beta-glucan fiber — whole or minimally processed barley is the food to reach for, not malt extract.

Malt and gluten: the part that matters most

Malt is barley, so malt contains gluten. The Celiac Disease Foundation lists malt in all its usual forms — malted barley flour, malted milk, malt extract, malt syrup, malt flavoring and malt vinegar — among the gluten-containing ingredients to avoid [Celiac Disease Foundation, Sources of Gluten].

U.S. labeling law backs that up. The FDA has stated plainly that malt extract and similar malt-derived ingredients come from a gluten-containing grain that has not been processed to remove gluten, so they cannot be used in any food carrying a “gluten-free” claim. Malt vinegar falls under the same restriction, because it is fermented rather than distilled [FDA, 2022]. A product labeled gluten-free should not contain malt at all; if you see malt in the ingredient list of something labeled gluten-free, that is a labeling problem, not a safe exception.

Malt hides in places people do not expect. Watch for it in:

• corn flakes and puffed rice cereals, which often use malt extract or malt flavoring
• malted milkshakes, malted milk powder and malt-ball candies
• potato chip seasonings, salad dressings and marinades containing malt vinegar
• brown rice syrup, which may be produced using barley enzymes
• beer and any malt beverage that is not explicitly labeled gluten-free

All of the above appear on the Celiac Disease Foundation’s list of gluten sources and foods that need label checking [CDF].

If you are building a gluten-free kitchen, our guides to foods to avoid with celiac disease and naturally gluten-free foods cover the wider shopping list.

Malt beverages, beer, and what “non-alcoholic” really means

Malt exists at industrial scale mostly because of fermentation: yeast converts the sugars malting created into alcohol. Beer is the familiar result, and whiskey starts the same way.

“Malt beverage” is also a regulated category in the U.S., and the labeling rules are more interesting than they look. A malt beverage may only be called “non-alcoholic” if the statement that it contains less than 0.5 percent alcohol by volume appears right next to the claim. Only a product containing no alcohol at all may be labeled “alcohol free” [TTB, Malt Beverage Labeling: Alcohol Content, 2023].

The practical takeaway: non-alcoholic does not mean alcohol-free. If you are pregnant, in recovery, avoiding alcohol for religious reasons, or taking a medication that interacts with it, read the label rather than the marketing, and ask your doctor or pharmacist if you are unsure.

Who should be careful with malt

• Anyone with celiac disease or a diagnosed gluten sensitivity. Malt in any form is off the list. This is not a moderation situation.
• People managing blood sugar. Malt syrup, malted milk drinks and malt-sweetened cereals are concentrated sugar. Our guide to diabetes-friendly food choices is a better starting point than any single ingredient swap.
• People who are pregnant or breastfeeding. Ordinary malt in bread or cereal is not the concern; alcohol is. Check the label on anything malt-based that you drink, and ask your doctor about alcohol during pregnancy rather than relying on a “non-alcoholic” claim.
• Anyone avoiding alcohol entirely. See the labeling rules above — the trace amount in a non-alcoholic malt beverage may still matter to you.
• Parents of young children. Malted milk drinks are marketed as nourishing, and they are largely sugar. Read the added sugars line.

Malt has no meaningful drug interactions of its own. Where interactions come in is alcohol: many common medications, including some antibiotics, sedatives, painkillers and diabetes drugs, carry alcohol warnings. If a malt beverage contains alcohol, your pharmacist is the right person to ask.

When to talk to a doctor

If eating foods that contain malt, barley, wheat or rye reliably leaves you with diarrhea, bloating, stomach pain, fatigue or mouth ulcers, see your doctor rather than experimenting on your own.

One detail matters enormously here: do not go gluten-free before you are tested. Celiac blood tests look for antibodies your immune system only produces while you are eating gluten, and NIDDK notes that accurate results require the patient to be on a gluten-containing diet [NIDDK, Celiac Disease Tests]. Cutting gluten first can turn a positive into a negative and cost you a diagnosis.

Seek urgent or emergency care — urgent care, the ER, or 911 if it is severe — for any of these:

• severe or persistent abdominal pain
• vomiting you cannot keep down, or signs of dehydration such as dizziness, confusion or very little urine
• black, tarry or bloody stools
• unintended weight loss, or a child who stops growing or gaining weight normally
• swelling of the lips, tongue or throat, trouble breathing, or hives after eating — signs of an allergic reaction, which is different from celiac disease and needs immediate care

HEALTH DISCLAIMER: This article is for general education and is not medical advice, diagnosis, or treatment. Celiac disease and gluten sensitivity are medical conditions that need a proper evaluation — do not diagnose yourself, and do not remove gluten from your diet before talking with your doctor, because testing is more accurate while gluten is still being eaten. If you are pregnant, breastfeeding, managing diabetes, taking prescription medication, or avoiding alcohol for any reason, talk with your doctor, registered dietitian, or pharmacist before making changes based on anything you read here.

Frequently Asked Questions

References

1. Lukinac, J., & Jukić, M. (2022). Barley in the Production of Cereal-Based Products. Plants, 11(24), 3519. doi:10.3390/plants11243519 (PMID 36559630). → View source
2. U.S. Food and Drug Administration. Questions and Answers on the Gluten-Free Food Labeling Final Rule. Content current as of June 30, 2022. → View source
3. Celiac Disease Foundation. Sources of Gluten. → View source
4. Alcohol and Tobacco Tax and Trade Bureau (TTB). Malt Beverage Labeling: Alcohol Content. TTB G 2023-2. → View source
5. National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Your Digestive System & How It Works. → View source
6. National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Celiac Disease Tests. → View source
7. U.S. Food and Drug Administration. Added Sugars on the Nutrition Facts Label (August 2023). → View source