The effect of pH on heat denaturation and gel forming properties of soy proteins
article
This study is focussed on the influence of pH on the gel forming properties of soy protein isolate and purified glycinin in relation to denaturation and aggregation. At pH 7.6 more fine-stranded gels were formed characterised by low G' values, and a smooth, slightly turbid appearance, whereas at pH 3.8 coarse gels were obtained with a high stiffness and a granulated, white appearance. Low G' values, as found at pH 7.6, correlate with a high solubility of glycinin and soy protein isolate (ca. 50%) after heating at low protein concentration. At pH 3.8 all protein precipitated upon heating, which correlates with relatively high G' values. The role of β-conglycinin during gelation of SPI seems to be minor at pH 7.6, which is indicated by the fact that, in contrast to pH 3.8, notable gel formation did not start upon heat denaturation of β-conglycinin. Furthermore, the mechanism of gel formation seems to be affected by pH, because at pH 7.6, in contrast to pH 3.8, the disulphide bridge between the acidic and the basic polypeptide of glycinin is broken upon heating. Copyright (C) 2000 Elsevier Science B.V.
Topics
Differential scanning calorimetryGlycininNetworkRheologySoy protein isolatebeta conglycinindisulfideglycininpolypeptideunclassified drugconference papercontrolled studydifferential scanning calorimetryflow kineticsfoodpHprecipitationprotein aggregationprotein denaturationtemperatureGelsGlobulinsHeatHydrogen-Ion ConcentrationProtein DenaturationSolubilitySoybean Proteins
TNO Identifier
280416
ISSN
01681656
Source
Journal of Biotechnology, 79(3), pp. 223-230.
Pages
223-230
Files
To receive the publication files, please send an e-mail request to TNO Repository.