(a) Identity. (1) The color additive soy leghemoglobin is a stabilized product of controlled fermentation of a non-pathogenic and non-toxicogenic strain of the yeast, Pichia pastoris, genetically engineered to express soy leghemoglobin protein. Soy leghemoglobin protein is the principal coloring component of the color additive and imparts a reddish-brown color.

(2) Color additive mixtures made with soy leghemoglobin may contain only those diluents that are suitable and are listed in this subpart as safe for use in color additive mixtures for coloring foods.

(b) Specifications. Soy leghemoglobin shall conform to the following specifications and shall be free from impurities, other than those named, to the extent that such impurities may be avoided by good manufacturing practice:

(1) Soy leghemoglobin protein purity on protein basis (weight/weight), not less than 65 percent, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

(2) Lead, not more than 0.4 milligrams per kilogram (mg/kg) (0.4 parts per million (ppm)).

(3) Arsenic, not more than 0.05 mg/kg (0.05 ppm).

(4) Mercury, not more than 0.05 mg/kg (0.05 ppm).

(5) Cadmium, not more than 0.2 mg/kg (0.2 ppm).

(c) Uses and restrictions. Soy leghemoglobin may be safely used in ground beef analogue products such that the amount of soy leghemoglobin protein does not exceed 0.8 percent by weight of the uncooked ground beef analogue product.

(d) Labeling. The label of the color additive and of any mixture prepared therefrom intended solely or in part for coloring purposes must conform to § 70.25 of this chapter.

(e) Exemption from certification. Certification of this color additive is not necessary for the protection of the public health, and therefore batches thereof are exempt from the certification requirements of section 721(c) of the Federal Food, Drug, and Cosmetic Act.