[Code of Federal Regulations] [Title 21, Volume 3] [Revised as of April 1, 2001] From the U.S. Government Printing Office via GPO Access [CITE: 21CFR172.180] [Page 35] TITLE 21--FOOD AND DRUGS CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) PART 172--FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION--Table of Contents Subpart B--Food Preservatives Sec. 172.180 Stannous chloride. The food additive stannous chloride may be safely used for color retention in asparagus packed in glass, with lids lined with an inert material, in an amount not to exceed 20 parts per million calculated as tin (Sn).