E466

E466 is the European food additive designation for carboxymethylcellulose (CMC), a cellulose-derived thickener and stabilizer used in a wide range of processed foods. The additive is most commonly used in its sodium salt form (CMC-Na), though calcium and potassium salts are also used in some applications. CMC provides viscosity, helps suspend particles, and improves texture without adding flavor.

Chemistry and production: Carboxymethylcellulose is produced by etherification of cellulose with monochloroacetic acid in alkaline conditions, yielding water-soluble carboxymethylcellulose salts. The resulting polymer is a long, highly hydrated chain that forms viscous solutions and gels over a broad pH range. The degree of substitution and the counterion (sodium, calcium, etc.) influence its thickening and stabilizing properties.

Applications: In foods, E466 acts as a thickener, stabilizer, and emulsifier in products such as ice cream, yogurt, dressings, sauces, custards, and gluten-free baked goods. It is also used in non-food products, including cosmetics and personal care items, pharmaceuticals as a binder or suspending agent, and various industrial formulations where rheology modification is needed.

Safety and regulation: Carboxymethylcellulose is widely regarded as safe for consumption at approved use levels. Regulatory assessments, including those by EFSA and the FDA, support its safety as a food additive, and no numerical acceptable daily intake is established because it is not absorbed and contributes negligible calories. However, very high intake may cause digestive discomfort or laxative effects in some individuals.