Three samples must be taken from the traced product in order to check on homogeneity. The analytical procedure described detects all substances absorbing at a wavelength of 440 nm. The apparent level of apo carotenic ester measured will be increased by these substances. The Expert Chemist Group of the EC Milk Management Committee set the specification limit to allow for the contribution from background absorption at 22 mg/kg for butter and 24 mg/kg for concentrated butter.
