acidity regulator INS 529

Calcium Oxide E529

processing aid, pH adjuster — Primarily mineral-derived.

🇪🇺 EU: Approved
🇺🇸 USA: Approved
🇯🇵 Japan: Approved
🇦🇺 AU/NZ: Approved
🇨🇦 Canada: Approved
Scientific Name

Calcium oxide (CaO)

CAS: 1305-78-8

Data verified: 2026-04-04

Factual Regulatory Reference

This database provides factual regulatory information compiled from official government sources. It does not constitute medical, nutritional, or safety advice. Regulatory status varies by country and is subject to change. Always refer to your local regulatory authority for the most current information.

? Did You Know?

Beyond food, Calcium Oxide is also used in cosmetics, medicine, industrial applications, household products. Its versatility makes it one of the most multi-purpose chemical compounds in everyday life.

In the EU, Calcium Oxide has a "quantum satis" authorization — Latin for "as much as needed." This means there's no specific maximum limit; manufacturers use only what's technologically necessary.

Detailed Regulatory Assessment

🇪🇺

European Union (EFSA)

approved Max: quantum satis mg/kg

Used as processing aid; typically hydrated to calcium hydroxide upon contact with moisture in food.

Official EFSA Link
🇺🇸

United States (FDA)

approved GRAS

Limited use; typically converts to calcium hydroxide in food applications.

🇯🇵

Japan (MHLW)

approved Cat: 指定添加物

Compliant with Japanese food sanitation law.

Acceptable Daily Intake (ADI)

International Standard (JECFA)

not specified (acceptable for use, converts to calcium hydroxide in food)

mg/kg body weight per day

European Standard (EFSA)

not specified (no safety concern)

Natural Occurrence

This additive is not known to occur naturally in significant quantities.

Manufacturing

Method: thermal decomposition of mineral

Produced by heating limestone (calcium carbonate, CaCO3) to very high temperatures (above 825°C) in a lime kiln. This drives off carbon dioxide, leaving calcium oxide. When water is added, it becomes calcium hydroxide (slaked lime).

Applications Beyond Food

Cosmetics

Rarely used.

Medical

Rarely used directly; converted to calcium hydroxide for pharmaceutical use.

Industrial

Steel manufacturing, cement production, glass manufacturing, paper production, water treatment.

Household

Historical use in lighting (limelight), hot packs (exothermic reaction with water).

Frequently Asked Questions

What is Calcium Oxide (E529)?
Calcium Oxide (E529) is a acidity regulator used in food products. It is processing aid, pH adjuster and mineral-derived. Calcium oxide does not occur naturally in free form (it reacts with moisture). It is produced by heating limestone (calcium carbonate) in kilns.
What is the ADI for Calcium Oxide?
The Acceptable Daily Intake (ADI) for Calcium Oxide is not specified (acceptable for use, converts to calcium hydroxide in food) as established by JECFA (Joint FAO/WHO Expert Committee on Food Additives). ADI represents the amount that can be consumed daily over a lifetime without appreciable health risk.
What foods contain Calcium Oxide?
Calcium Oxide is used in various food categories including Canned or bottled vegetables. It is used as a acidity regulator in these products.
Is Calcium Oxide the same as Quicklime?
Yes, Calcium Oxide is also known as Quicklime, Burnt lime, Unslaked lime, Calx. These are different names for the same substance.