Kinetic Modeling of Malonylgenistin and Malonyldaidzin Conversions under Alkaline Conditions and Elevated Temperatures
- 30 March 2007
- journal article
- research article
- Published by American Chemical Society (ACS) in Journal of Agricultural and Food Chemistry
- Vol. 55 (9), 3408-3413
- https://doi.org/10.1021/jf063511z
Abstract
The conversion and degradation of malonylglucosides were kinetically characterized under elevated pH/heat conditions. Malonylgenistin and malonyldaidzin were heated at 60, 80, and 100 °C and pH values of 8.5, 9, and 9.5. A simple kinetic model was developed, which adequately predicted the conversion and degradation reactions. The conversion and degradation rates increased as temperature and pH increased. The rates of conversion of both malonylglucosides into their respective β-glucosides were comparable under all pH/heat treatments. However, at 100 °C, the rates of degradation of malonyldaidzin were approximately double those of malonylgenistin, under all pH treatments. When malonlydaidzin was heated at 100 °C and pH 9.5, degradation of the produced daidzin occurred. Therefore, an alternative kinetic model was developed to better predict the conversion and degradation of malonyldaidzin occurring at 100 °C and pH 9.5. The models developed provide soy food manufacturers with guidelines for better control of the profile and level of isoflavones. Keywords: Isoflavones; β-glucosides; malonylglucosides; kinetics; isoflavone conversions and degradationsKeywords
This publication has 8 references indexed in Scilit:
- Heat and pH Effects on the Conjugated Forms of Genistin and Daidzin IsoflavonesJournal of Agricultural and Food Chemistry, 2006
- Soybean isoflavones: Efficacy of extraction conditions and effect of food type on extractabilityFood Research International, 2005
- β-Glycosidase Activity toward Different Glycosidic Forms of IsoflavonesJournal of Agricultural and Food Chemistry, 2005
- Kinetic model for studying the conversion and degradation of isoflavones during heatingFood Chemistry, 2004
- Thermal Stability of Genistein and Daidzein and Its Effect on Their Antioxidant ActivityJournal of Agricultural and Food Chemistry, 2003
- Solvent extraction selection in the determination of isoflavones in soy foodsJournal of Chromatography B, 2002
- Isoflavones and their conjugates in soy foods: extraction conditions and analysis by HPLC-mass spectrometryJournal of Agricultural and Food Chemistry, 1994
- Nonlinear Regression Analysis and Its ApplicationsWiley Series in Probability and Statistics, 1988