E250

E250 is the European food additive designation for sodium nitrite (chemical formula NaNO2). It is a white to pale yellow crystalline solid used primarily as a curing agent and preservative in meat and fish products. As a nitrite, it helps prevent the growth of certain bacteria and contributes to the characteristic pink-red color of cured meats.

In food processing, E250 serves two main roles. It acts as an antimicrobial agent, especially against Clostridium botulinum, and it functions as a color fixative by reacting with myoglobin to form stable nitrosyl compounds that give cured meats their distinctive appearance. It is commonly used together with nitrate-containing curing systems and is typically applied at regulated, product-specific levels.

Regulation and safety considerations. In the European Union, E250 is approved as a food additive with purity specifications and usage limits that vary by product type. The European Food Safety Authority has established an Acceptable Daily Intake (ADI) for nitrites of 0–0.07 mg per kilogram of body weight per day (as nitrite). Labeling requirements apply to products containing nitrite, and certain products or organic certifications may restrict or prohibit its use.

Health considerations. High nitrite exposure can cause methemoglobinemia, a condition that reduces the blood’s ability to carry oxygen. Nitrites can also react to form nitrosamines, compounds that have raised cancer risk concerns under some conditions; the formation is mitigated by limiting nitrite levels and adding antioxidants such as ascorbic acid. Proper storage, cooking, and adherence to regulatory limits help manage potential risks.

See also: food additive, nitrite, nitrate, curing salt.