TY - JOUR
T1 - Influence of salt and pH on the solubility and structural characteristics of transglutaminase-treated wheat gluten hydrolysate
AU - Agyare, Kingsley K.
AU - Xiong, Youling L.
AU - Addo, Kwaku
PY - 2008/4/1
Y1 - 2008/4/1
N2 - Hydrolyzed wheat gluten (GH, 77-85% protein) was prepared by limited chymotrypsin digestion at 37 °C for 4 h (degree of hydrolysis = 6.4%) and 15 h (degree of hydrolysis = 10.3%). Microbial transglutaminase (MTGase) treatment (55 °C for 1 h, or 5 °C for 18 h) effect on the solubility and structural characteristics of GH was examined under selected food processing conditions (pH 4.0-7.0, 0-0.6 M NaCl). The MTGase treatment increased solubility of GH by 3-29-fold (P < 0.05) within pH 4.0-7.0. Addition of 0.6 M NaCl or changing the conditions of MTGase incubation did not significantly alter solubility characteristics of GH. The MTGase treatment decreased surface hydrophobicity, and increased carboxyl groups in GH, suggesting cross-linking and deamidation. Fluorescence and UV spectra attributed the improved GH solubility to MTGase-induced polar environment, and partial masking of some nonpolar aromatic amino acids possibly due to high-molecular-weight polypeptides formed.
AB - Hydrolyzed wheat gluten (GH, 77-85% protein) was prepared by limited chymotrypsin digestion at 37 °C for 4 h (degree of hydrolysis = 6.4%) and 15 h (degree of hydrolysis = 10.3%). Microbial transglutaminase (MTGase) treatment (55 °C for 1 h, or 5 °C for 18 h) effect on the solubility and structural characteristics of GH was examined under selected food processing conditions (pH 4.0-7.0, 0-0.6 M NaCl). The MTGase treatment increased solubility of GH by 3-29-fold (P < 0.05) within pH 4.0-7.0. Addition of 0.6 M NaCl or changing the conditions of MTGase incubation did not significantly alter solubility characteristics of GH. The MTGase treatment decreased surface hydrophobicity, and increased carboxyl groups in GH, suggesting cross-linking and deamidation. Fluorescence and UV spectra attributed the improved GH solubility to MTGase-induced polar environment, and partial masking of some nonpolar aromatic amino acids possibly due to high-molecular-weight polypeptides formed.
KW - Hydrolyzed wheat gluten
KW - Microbial transglutaminase
KW - Solubility
KW - Structural properties
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U2 - 10.1016/j.foodchem.2007.09.039
DO - 10.1016/j.foodchem.2007.09.039
M3 - Article
AN - SCOPUS:36348995909
VL - 107
SP - 1131
EP - 1137
IS - 3
ER -