acidity regulator INS 526

Calcium Hydroxide E526

firming agent, processing aid, pH adjuster — Primarily mineral-derived.

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

Calcium hydroxide (Ca(OH)2)

CAS: 1305-62-0

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?

Calcium Hydroxide occurs naturally in Portlandite mineral (rare) and Formed when calcium oxide reacts with water. Many people consume it daily without realizing it's also a listed food additive.

Beyond food, Calcium Hydroxide 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 Hydroxide 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

Permitted as processing aid and firming agent; excess is washed away or neutralized.

Official EFSA Link
🇺🇸

United States (FDA)

approved GRAS

Widely used in traditional food processing, especially nixtamalization and pickling.

🇯🇵

Japan (MHLW)

approved Cat: 指定添加物

Used in traditional food processing.

Acceptable Daily Intake (ADI)

International Standard (JECFA)

not specified (acceptable for use, mostly removed during processing)

mg/kg body weight per day

European Standard (EFSA)

not specified (no safety concern at current use levels)

Natural Occurrence

While calcium hydroxide can form naturally, commercial production is by reacting quicklime (calcium oxide) with water. The calcium oxide itself comes from heating limestone.

Portlandite mineral (rare)Formed when calcium oxide reacts with water

Manufacturing

Method: chemical synthesis from mineral

Produced by reacting calcium oxide (quicklime) with water in an exothermic 'slaking' reaction. The calcium oxide is obtained by heating limestone (calcium carbonate) to high temperatures. Food-grade calcium hydroxide is purified to remove impurities.

Applications Beyond Food

Cosmetics

Rarely used; pH adjuster in some formulations.

Medical

Dental applications (root canal treatment), antacid formulations.

Industrial

Cement and mortar, water treatment, leather tanning, soil stabilization, plaster.

Household

Traditional whitewash, pickling (making pickles crisp).

Frequently Asked Questions

What is Calcium Hydroxide (E526)?
Calcium Hydroxide (E526) is a acidity regulator used in food products. It is firming agent, processing aid, pH adjuster and mineral-derived. While calcium hydroxide can form naturally, commercial production is by reacting quicklime (calcium oxide) with water. The calcium oxide itself comes from heating limestone.
Where is Calcium Hydroxide found naturally?
Calcium Hydroxide is naturally found in Portlandite mineral (rare), Formed when calcium oxide reacts with water. While calcium hydroxide can form naturally, commercial production is by reacting quicklime (calcium oxide) with water. The calcium oxide itself comes from heating limestone.
What is the ADI for Calcium Hydroxide?
The Acceptable Daily Intake (ADI) for Calcium Hydroxide is not specified (acceptable for use, mostly removed during processing) 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 Hydroxide?
Calcium Hydroxide is used in various food categories including Canned or bottled vegetables, Fresh pastas and noodles. It is used as a acidity regulator in these products.
Is Calcium Hydroxide the same as Slaked lime?
Yes, Calcium Hydroxide is also known as Slaked lime, Hydrated lime, Pickling lime, Cal (Spanish/Latin American), Calcium hydrate. These are different names for the same substance.