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Stability of Tryptophan in Peptides Against Oxidation and Irradiation

  • H. Steinhart
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 294)

Abstract

Tryptophan (trp) is an essential amino acid for humans and most animals. It is, however, not the first and second limiting essential amino acid, but about 30% of the plant proteins used for human nutrition show a deficiency of trp. Besides cysteine, methionine and lysine, it belongs to the most reactive amino acids, which are endangered especially during food manufacturing processes. Friedman and Cuq (1988) recently reviewed the transformations of trp in foods. They report a lack of information of data concerning the stability of trp against industrial or home processing. Processing techniques, however, can cause losses in the trp content of food. Oxidations are of high significance. The most important reason for the instability of trp, especially against oxidizing agents and irradiation, is the bulky nonpolar aromatic side chain.

Keywords

Degradation Product Essential Amino Acid Aliphatic Amino Acid Amber Vial Neighboring Amino Acid 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Press, New York 1991

Authors and Affiliations

  • H. Steinhart
    • 1
  1. 1.Institute of Biochemistry and Food ChemistryUniversity of HamburgHamburgGermany

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