E529 — Calcium Oxide

Calcium oxide (CaO), commonly known as quicklime or burnt lime, is an inorganic compound used in various industrial and food processing applications. It appears as a white, caustic, alkaline, crystalline solid at room temperature. 

Danger Level: 3 — Hazardous

Purpose in Products

In the food industry, calcium oxide serves several functions:

  • Acidity Regulator: It adjusts the pH levels in food products, ensuring proper acidity.
  • Processing Aid: Calcium oxide is used in the production of white sugar to remove impurities. 
  • Firming Agent: It is utilized in the preparation of certain foods, such as pickles, to maintain firmness. 

Health Considerations

Calcium oxide is a strong alkaline substance that can cause severe chemical burns upon contact. However, when used in food processing, it is typically present in very low concentrations, and the final product contains negligible amounts, making it safe for consumption. The European Food Safety Authority (EFSA) has not established an acceptable daily intake (ADI) for calcium oxide, indicating no safety concern at the reported uses and use levels. 

Impact on Children

Calcium oxide is safe for children when present in food products at the levels typically used in food processing.

Impact on Taste

Calcium oxide is tasteless and odorless, making it an ideal ingredient for various food products without altering their flavor profiles.

Compatibility with Other Additives

Calcium oxide is compatible with various other food additives, including sugars and other hydrocolloids. Its water-binding properties make it suitable for use in products requiring moisture retention.

Natural Occurrence

Calcium oxide is not naturally occurring in foods but is synthetically produced for use as a food additive.

Alternatives and Substitutes

For those seeking alternatives to E529, options include:

  • Calcium Hydroxide (E526): Used as an acidity regulator and firming agent.
  • Magnesium Oxide (E530): Serves as an acidity regulator and anti-caking agent.

Regulation

Calcium oxide is approved for use as a food additive in many countries, including the European Union, where it is designated as E529. Regulatory bodies such as the European Food Safety Authority (EFSA) have evaluated its safety and concluded that it poses no health concerns when used within established limits. 

Conclusion

Calcium oxide (E529) is a versatile and safe food additive used primarily as an acidity regulator, processing aid, and firming agent. Its unique properties make it valuable in various food products, enhancing texture and stability. While generally safe, individuals with specific sensitivities should exercise caution.