21 CFR § 184.1271 - L-Cysteine.
(a) L-Cysteine is the chemical L-2-amino-3-mercaptopropanoic acid (C3H7O2NS).
(b) The ingredient meets the appropriate part of the specification set forth in the “Food Chemicals Codex,” 3d Ed. (1981), pp. 92-93, which is incorporated by reference. Copies may be obtained from the National Academy Press, 2101 Constitution Ave. NW., Washington, DC 20418, or may be examined at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.
(c) The ingredient is used to supply up to 0.009 part of total L-cysteine per 100 parts of flour in dough as a dough strengthener as defined in § 170.3(o)(6) of this chapter in yeast-leavened baked goods and baking mixes as defined in § 170.3(n)(1) of this chapter.
(d) This regulation is issued prior to a general evaluation of use of this ingredient in order to affirm as GRAS the specific use named.