Nonenzymatic deamidation of food proteins

W E Riha1, H V Izzo, J Zhang

  • 1Department of Food Science, Cook College, Rutgers, State University of New Jersey, New Brunswick 08903, USA.

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Amides to Carboxylic Acids: Hydrolysis

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Acid-catalyzed hydrolysis:
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Secondary amines react with nitrous acid to form N-nitrosamines, as depicted in Figure 1. Nitrous acid, a weak and unstable acid, is formed in situ from an aqueous solution of sodium nitrite and strong acids, such as hydrochloric acid or sulfuric acid, in cold conditions. In the presence of an acid, the nitrous acid gets protonated. The subsequent loss of water results in the formation of the electrophile known as nitrosonium ion.
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Protein Denaturation

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