What is E170 (Calcium Carbonate)?
E170 is the European food additive code for calcium carbonate, a natural mineral compound found in sources like limestone, chalk, and marble. It is a fine, odorless, and tasteless white powder that is a common substance both in nature and for industrial uses. The compound is practically insoluble in water, which makes it effective for specific functions in food processing. Due to its natural origins and versatile properties, it has been used in food and pharmaceutical products for many years. While the designation E170 most commonly refers to calcium carbonate, there is also a subtype, E170(ii), for acidic calcium carbonate, though this is less common.
Versatile Uses of E170 in Food
The versatility of calcium carbonate is why it's found in such a wide range of products. It serves multiple functions, often helping with texture, stability, and nutritional value.
As a Food Colorant and Opacifier
As a brilliant white powder, E170 is often used as a colorant to whiten and brighten certain food items. This makes it a natural alternative to synthetic dyes, which is appealing to many consumers.
- Examples: White confectionery, icings, and glazes.
As a Nutritional Supplement
Calcium carbonate is an excellent source of dietary calcium, an essential mineral for bone health. Many products are fortified with E170 to boost their calcium content.
- Examples: Calcium-fortified beverages like orange juice and non-dairy milks, as well as breakfast cereals.
As an Acidity Regulator
E170 is a base that can neutralize excess acid in food products, helping to control the pH level. This can be crucial for extending shelf life and ensuring consistent product quality.
- Examples: Some baked goods and canned foods.
As an Anti-caking Agent
In powdered food products, calcium carbonate prevents clumping and ensures that the powder flows freely. Its fine particle size helps keep the product from sticking together.
- Examples: Spices, baking mixes, and table salt.
As a Firming Agent and Stabilizer
E170 is used to maintain the texture and firmness of certain foods, especially canned fruits and vegetables. It helps prevent them from becoming soft or mushy during processing.
- Examples: Canned fruits, preserves.
As a Flour Treatment Agent
In the baking industry, E170 is added to flour, especially white flour, to replace calcium lost during the refining process. This helps improve dough handling and baking performance.
How E170 is Sourced and Produced
The calcium carbonate used in the food industry is primarily sourced from geological deposits or produced synthetically for high purity.
Natural Sourcing
Most industrial calcium carbonate is extracted from mined rock sources like limestone, chalk, and marble. For food-grade applications, the material is then purified to meet strict regulatory standards.
Synthetic Production
Another method is the precipitation process, which produces a highly pure form known as Precipitated Calcium Carbonate (PCC). This involves treating calcium oxide with water to form calcium hydroxide, then passing carbon dioxide through the solution to precipitate the calcium carbonate. This process ensures a consistent and high-quality product for sensitive applications like food and pharmaceuticals.
Regulatory Status and Safety of E170
Calcium carbonate (E170) is approved for use in food products by major regulatory bodies globally, including the European Food Safety Authority (EFSA) and the U.S. FDA. In its re-evaluation, EFSA found no safety concerns at current usage levels and concluded there is no need to set a numerical acceptable daily intake (ADI) for calcium carbonate itself. However, EFSA did note concerns regarding the presence of aluminum impurities and requested further data on this.
Potential Side Effects and Considerations
While generally considered safe, consuming excessive amounts of E170 as a supplement can lead to side effects. These are typically associated with extremely high doses and are relatively rare in food applications. Common side effects can include:
- Upset stomach
- Constipation
- Belching or bloating
- Nausea
Furthermore, high calcium levels (hypercalcemia) from excessive intake can lead to more serious issues like kidney problems over time. It is also explicitly stated that E170 is not intended for use in foods for infants and young children, particularly those under 16 weeks.
E170 and Dietary Restrictions: Halal and Vegan Considerations
For those following specific dietary guidelines, the origin of E170 is an important factor. As it can be sourced from both mineral deposits and animal products like shells, verification is sometimes necessary.
- Vegan: For vegans, the source is critical. Calcium carbonate can be derived from ground rock (limestone, marble), which is vegan-friendly. However, it can also be sourced from animal materials like crushed snail shells, eggshells, or oyster shells. While most commercial food-grade E170 is derived from geological sources for cost-effectiveness, it is best to check for a vegan label or contact the manufacturer to be 100% certain.
- Halal: According to some Islamic authorities, E170 is considered halal if it is obtained from a mineral rock source and used as a dry powder. If used as a liquid, the solvent must also be halal.
Comparison of Food Additives: E170 vs. E509
To illustrate E170's unique properties, here's a comparison with another calcium-based additive, E509 (Calcium Chloride).
| Feature | E170 (Calcium Carbonate) | E509 (Calcium Chloride) |
|---|---|---|
| Primary Function | Colorant, anti-caking, acidity regulator, firming agent, nutritional supplement | Acidity in taste, protein-decomposing effect, gelling aid |
| Appearance | Fine, odorless, tasteless white powder | Colorless, solid crystalline substance |
| Solubility | Practically insoluble in water | Highly soluble in water |
| Effect in Food | Whitens, prevents clumping, regulates pH, firms texture, adds calcium | Enhances gelling in jams, treats water, affects taste |
| Common Uses | Baked goods, cereals, spices, milk alternatives | Cheese making, brewing yeast production, canned foods |
Conclusion
E170 is the food additive code for calcium carbonate, a safe and versatile mineral compound with many applications in the food industry. From acting as a white pigment in confectionery to serving as an anti-caking agent in powdered goods, its functions are diverse. It is also an excellent source of dietary calcium for fortification. While generally safe, sourcing matters for vegans, and excessive intake should be avoided. As a widely regulated and approved additive, E170 remains a common and beneficial ingredient in a variety of processed foods, but understanding its properties helps consumers make more informed choices about their diet. For the most up-to-date information on regulatory matters, refer to official sources like the European Food Safety Authority.
This article is for informational purposes only and does not constitute medical or dietary advice. Always consult a healthcare professional for health-related decisions.
