What is E529?
Calcium oxide (E529) is an acidity regulator and processing aid used in specified food applications. Goodnessly rates E529 Safe, while food-category permissions and the relevant regulator assessment still apply.
Calcium oxide (E529) is an acidity regulator and processing aid used in specified food applications. Goodnessly rates E529 Safe, while food-category permissions and the relevant regulator assessment still apply. Check the food category, amount and full formulation rather than judging one ingredient in isolation.
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Read the FAQ →
What is Calcium oxide?
Calcium oxide is a strongly alkaline calcium compound also known as quicklime. In food processing it can adjust acidity or support particular preparation steps when the applicable food standard permits it.
What's it used for?
- Adjusting acidity in permitted foods
- Supporting processing steps such as treatment of some foods
- Providing a calcium source in specified applications
- Helping manage pH in permitted formulations
Where you'll find E529 on the shelf
You may see E529 in selected processed foods, food ingredients or nutrient-related formulations where an alkaline calcium compound has a permitted technical or nutritional role.
Is E529 permitted? What the regulators say
E529 is listed or permitted in the three systems checked, with category, level, purity and specification conditions applying.
| Region | Status | What this means |
|---|---|---|
| AU/NZ Australia & New Zealand (FSANZ) | Permitted with conditions | FSANZ lists 529 calcium oxide in the Food Standards Code; Schedule 15 food-category conditions and levels apply. [FSANZ/source] |
| EU European Union (EUR-Lex) | Authorised with conditions | The Union list includes E529 calcium oxide for specified food uses and conditions. [FSANZ/source] |
| US United States (FDA) | GRAS with GMP conditions | FDA affirms calcium oxide as GRAS for direct human food use under 21 CFR 184.1210, subject to current good manufacturing practice. [FSANZ/source] |
Goodnessly rates E529 Safe within its rating system. The rating does not remove the need to consider the product category, amount or full formulation.
- JECFA assigned calcium oxide an ADI of “not limited” at its 9th meeting in 1965; Codex records the same assessment.
- EFSA has an ongoing data and use-level programme for E529; no new final EFSA ADI has been published in the checked sources.
- An ADI or “not limited” conclusion is a population risk-assessment reference, not a statement that every product or use is interchangeable.
This section is checked periodically rather than continuously — confirm the current primary source before relying on a regulatory detail.
Who might want to limit or avoid it
- People comparing acidity regulators
- People checking the form and amount of added calcium in a product
- People who want to consider the whole formulation and serving pattern
Goodnessly rates E529 Safe as a practical prompt to understand the ingredient, the product and the overall formulation.
How to spot it on a label
Look for:
- Calcium oxide
- 529 or E529
- Acidity regulator (529)
- Acidity regulator (E529)
Ingredient labels may use the name, the number, or the additive class followed by the number.
Related additives
Frequently asked questions
What is E529?
E529 is calcium oxide, an acidity regulator and processing aid used in specified food applications.
Is E529 permitted?
E529 is permitted with conditions in Australia/New Zealand and the EU. FDA affirms calcium oxide as GRAS for direct human food use under current good manufacturing practice.
Does calcium oxide have an ADI?
JECFA lists an ADI of “not limited” for calcium oxide. EFSA has an ongoing data and use-level programme, with no new final ADI in the checked sources.
How does Goodnessly rate E529?
Goodnessly rates E529 (calcium oxide) as Safe within its rating system.
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