albumin - publications
Heat-induced cross-linking and degradation of wheat gluten, serum albumin, and mixtures thereof.
J Agric Food Chem. 2012 Sep 5;
Authors: Rombouts I, Lagrain B, Delcour JA
Some wheat-based food systems, such as cakes, cookies and egg noodles, contain mixtures of animal and plant (gluten) proteins and are processed under (mildly) alkaline conditions. Although changes in these proteins during processing can impact end product quality, they have seldom been studied. We investigated protein cross-linking and degradation during heating (0-120 min, pH 8.0, 50-130 °C) of (mixtures of) wheat gluten and bovine serum albumin (BSA). The decrease in protein extractabilities in sodium dodecyl sulfate containing buffer under (non-)reducing conditions and the levels of (cross-linked) amino acids were measured. No indications for polymerization at 50 °C were found. Below 100 °C, BSA polymerized more readily than wheat gluten. Above 100 °C, the opposite was observed. The kinetics of heat-induced polymerization of a 1:1 gluten-BSA mixture were similar to that of isolated gluten implying that gluten decelerated BSA denaturation. Severe heating (130 °C, >15 min) induced degradation reactions in gluten but not in BSA. At all conditions used in this study, disulfide (SS) bonds contributed to the extractability loss. In addition, above 110 °C, β-elimination of cystine led to non-SS cross-links. Intramolecular SS bonds more often transformed in intermolecular non-SS bonds in BSA than in gluten.
PMID: 22950662 [PubMed - as supplied by publisher]