E575 - Glucono-delta-lactone

At a glance

• Names you might see: glucono-delta-lactone, GDL, gluconolactone
• What it does: gentle acidulant, leavening acid, sequestrant (binds metal ions), firming and curing aid
• How it works: slowly releases acid as it hydrates, giving smooth, even acidification
• Where it’s used: tofu, baked goods, processed meats, sauces, dairy-style products
• Regulatory status: allowed in the U.S. as Generally Recognized as Safe (GRAS) and listed in the EU as E575

Why is Glucono-delta-lactone added to food?

GDL provides a slow, steady release of acidity. This helps set textures and develop flavor without a harsh sour taste. It serves as a leavening acid in baking (it reacts with baking soda to make carbon dioxide gas) and as a sequestrant, which means it binds trace metals that could cause off-flavors or color changes.¹ It is recognized by U.S. regulators as a multipurpose ingredient used under good manufacturing practice as a pH control agent, leavening agent, curing and pickling aid, and sequestrant.¹

What foods contain Glucono-delta-lactone?

You may find GDL in:

• Tofu and similar soy products, where it helps form a smooth, tender gel
• Baked goods and batters, paired with sodium bicarbonate for controlled leavening
• Processed meats and fish, as part of curing or pickling blends
• Cheese-style and cultured dairy-style products, where gentle acidification is useful
• Sauces, dressings, and ready-to-eat meals that need mild pH adjustment

In the European Union, it appears on labels as E575, confirming it is an authorized food additive.²

What can replace Glucono-delta-lactone?

Alternatives depend on the job you need done:

• For pH control or a sharper sour taste: citric acid or lactic acid
• For leavening systems: diphosphates such as disodium diphosphate, often used with sodium bicarbonate
• For firming or pickling help: salts like calcium chloride in some applications

Note that these substitutes act faster or taste more sour than GDL, so recipes may need adjustment.

How is Glucono-delta-lactone made?

Commercial GDL is produced by fermenting a carbohydrate, usually glucose, with safe food-grade microorganisms to make gluconic acid. The gluconic acid solution is then purified and crystallized to form GDL, which is the cyclic ester (lactone) of D‑gluconic acid.¹ In water, GDL gradually hydrolyzes back to gluconic acid, explaining its slow acid release.³

Is Glucono-delta-lactone safe to eat?

In the United States, GDL is affirmed as Generally Recognized as Safe (GRAS) when used in line with current good manufacturing practice, and its identity and permitted functions are defined in federal regulations.¹ In the European Union, it is listed as E575 in the food additives framework and has official purity specifications, which means it is authorized for use subject to EU rules.²⁴

Does Glucono-delta-lactone have any benefits?

• Gentle flavor: It acidifies slowly, which can reduce sharp, immediate sourness compared with stronger acids.
• Texture control: The gradual pH drop can produce smoother gels in products like tofu and help set dairy-style textures.
• Reliable leavening: In baking, its controlled reaction with sodium bicarbonate supports even rise and crumb structure.

Who should avoid Glucono-delta-lactone?

Most people do not need to avoid GDL. It is not a common allergen, and it is used at low levels. If you are on a physician-prescribed low-acid diet or have specific sensitivities to acidic foods, check labels and discuss with your healthcare professional.

Myths & facts

• “It’s a harsh acid.” False. GDL is a mild acidulant that releases acidity slowly as it converts to gluconic acid.³
• “It’s not allowed in the EU.” False. It is authorized as E575 with defined specifications.²⁴
• “It always tastes sour.” Not necessarily. Because its acid release is gradual, many foods use it to fine‑tune texture with minimal sharpness.

Glucono-delta-lactone in branded foods

On ingredient lists, look for “glucono-delta-lactone,” “GDL,” or “gluconolactone.” In the EU, the name may appear with its E‑number, “E575.” You’ll most often see it in tofu, cake mixes, refrigerated doughs, cured or pickled meats, and some sauces and dairy-style products. Related ingredients made from gluconic acid, like potassium gluconate and calcium gluconate, may appear in mineral-fortified foods.

References

Footnotes

1. 21 CFR 184.1318 — Glucono delta-lactone. ecfr.gov https://www.ecfr.gov/current/title-21/chapter-I/subchapter-B/part-184/subpart-B/section-184.1318 ↩ ↩² ↩³ ↩⁴

2. Regulation (EC) No 1333/2008 on food additives — European Union. https://eur-lex.europa.eu/eli/reg/2008/1333/oj ↩ ↩² ↩³

3. Glucono-1,5-lactone — PubChem, National Institutes of Health. https://pubchem.ncbi.nlm.nih.gov/compound/Glucono-1_5-lactone ↩ ↩²

4. Commission Regulation (EU) No 231/2012 (specifications for food additives) — European Union. https://eur-lex.europa.eu/eli/reg/2012/231/oj ↩ ↩²