Article

Semicarbazide formation in azodicarbonamide-treated flour: A model study

Food Research Division, Bureau of Chemical Safety, Health Products and Food Branch, Health Canada, Address Locator 2203D, Ottawa, Ontario K1A 0L2, Canada.
Journal of Agricultural and Food Chemistry (Impact Factor: 3.11). 10/2004; 52(18):5730-4. DOI: 10.1021/jf0495385
Source: PubMed

ABSTRACT Semicarbazide was previously found in foods that were in contact with rubber gaskets foamed at high temperatures with a blowing agent azodicarbonamide. Because azodicarbonamide is an approved flour additive in certain countries, we set out to ascertain if semicarbazide is formed during the baking process from flours containing that additive. The levels of semicarbazide in baking flour treated with azodicarbonamide and bread baked from such flours were determined by isotope dilution (13C15N2-semicarbazide) liquid chromatography electrospray tandem mass spectrometry (LC-MS/MS). The samples were homogenized with HCl, extracted with n-pentane, derivatized with 2-nitrobenzaldehyde, and the derivative was extracted with ethyl acetate. After solvent exchange to 10% acetonitrile in water containing 0.1% acetic acid, the samples were analyzed using a 2.1 mm x 150 mm C18 column eluted with 2 mM ammonium formate in water/methanol (40:60). Semicarbazide was formed during the dry heating of commercial azodicarbonamide-containing flours at temperatures of 150-200 degrees C reaching levels of 0.2 mg/kg. Similar levels of semicarbazide were found in the crusts of breads made from azodicarbonamide-treated flour.

2 Followers
 · 
470 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: The recently instituted and easily accessible Rapid Alert System for Food and Feed (RASFF) has been tested on the semicarbazid (SEM), the residue of veterinary antibiotic nitrofurazone, using the RASFF Data- base Portal launched in July 2009 by the European Commission. The database holds weekly overviews, published by the EU for 30 years from 1979 and offers a number of other possibilities, such as searching for subjects of notification, the date of notification, notifying countries and product categories, countries of product origin and distribution. There is no doubt that the new database portal is an important contribution of the European Union to food safety and consumer protection.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: This study was conducted to establish a method to analyze biurea decomposed from azodicarbonamide in processed foods such as wheat flour and bread. New method was developed using high performance liquid chromatography mass/mass spectrometry to determine biurea in wheat flour and bakery products. The recovery rate was 94.3-112.5%. The limit of detection for biurea was 0.003 mg/kg, and the limit of quantification was 0.01 mg/kg. The monitoring results for biurea content using established methods showed that biurea was detected at 2.76 mg/kg in the azodicarbonamide-detected flour (detection rate, 2%). The detection rate in processed foods such as baked goods was 27% (16/59). The detection range was 0.19-18.01 mg/kg (average, 3.79 mg/kg). However, it was thought that the detection level was safe due to much lower values than the standard (45 mg/kg). As a result, the newly established biurea analytical method will contribute to the management of azodicarbonamide in processed foods such as wheat flour and bakery products.
    01/2010; 42(4).
  • [Show abstract] [Hide abstract]
    ABSTRACT: Herein voltammetric behaviors of semicarbazide (SEM) are investigated by employing a graphene modified working electrode, which displays attractive electroanalytical properties. In the acetate buffer solution of pH 4.00, there is a well-defined oxidative peak of SEM, attributing to the irreversible and adsorption-controlled electrode reaction with 2 electrons participation. The values of apparent heterogeneous electron transfer rate constant k′s with the redox are 0.0061 s−1 and 0.0009 s−1, respectively, for two scan rate section. After the experimental parameters, which influence the voltammetric responses of SEM, including supporting electrolyte, pH, accumulation time and accumulation potential, etc., are optimized, it is found that the anodic peak current of SEM is proportional to its concentration in the range of 4 - 40 μmol/L with a detection limit of 1 μmol/L (S/N = 3). Then, an electrochemical method for detecting SEM quantitatively is developed successfully. The concentrations of SEM in fortified tap water samples are tested with satisfactory recovery, indicating that the novel method is strongly promising in the environmental monitoring application.
    06/2014; 61(6). DOI:10.1002/jccs.201300530