<< Back to Abstract Listing by Category Board Number: I-31 Title: The Determination of Semicarbazide (N-aminourea) in Commercial Bread Products G. O. Noonan 1 , C. R. Warner 1 , W. Hsu 2 , T. H. Begley 1 , G. A. Perfetti 1 , G. W. Diachenko 1 , 1 CFSAN, FDA, College Park, MD , 2 JIFSAN, FDA, College Park, MD                     Recently semicarbazide has been found in food in jars sealed with cap liners that were manufactured using azodicarbonamide as a blowing agent.  These reports raised the concern that the use of azodicarbonamide-an approved dough conditioner-may result in semicarbazide residues in bread.  To answer this question, a method based upon the previously reported HPLC/MS determination of the semicarbazone of o-nitrobenzaldehyde (NBA) was utilized.  The method adopted for this work includes an extensive cleanup and reaction with NBA at pH 3.5, rather than with the widely used 0.1 M HCl (HCl), to form the semicarbazone derivative.  Stable isotope dilution assay (SIDA) was used to determine the free semicarbazide present in the bread products.  Levels of semicarbazide ranged from 10 ppb to 1200 ppb in commercial bread products with azodicarbonamide listed among their ingredients. Category: I. Analytical Chemistry: Methods Development and Applications