SUMMARY— The melting point and 1 1% cm‐values of a‐bixin, β‐bixin, and a‐norbixin were determined and the stability of a‐bixin examined under different conditions. The total pigment content of butter colors was determined. a‐Bixin was the principal pigment; in addition, at least eight different pigments were present. The content of a‐ and β‐bixin in butter colors was also determined. Because of complex formation of bixin and norbixin with a yellow pigment, the simple chromatographic method became rather laborious. This complex formation did not occur in the annatto suspensions in oil and fat. These preparations were more concentrated, while the amount of decomposition products of a‐bixin was relatively slight. The stability of the pigments in butter colors appeared to be great. Investigation of annatto cheese colors showed that these extracts contain at least seven color components. The total amount of red pigment and the principal pigment a‐norbixin were determined.