Lievonen Satu M, Laaksonen Tommi J, Roos Yrjö H
Department of Food Technology, P.O. Box 27, FIN-00014 University of Helsinki, Finland.
J Agric Food Chem. 2002 Nov 20;50(24):7034-41. doi: 10.1021/jf0255275.
Effects of a reducing sugar, fructose, glucose, or xylose, and glass transition on the nonenzymatic browning (NEB) rate in maltodextrin (MD), poly(vinylpyrrolidone) (PVP), and water systems were studied. Glass transition temperatures (T(g)) were determined using DSC. Water contents were determined gravimetrically, and NEB rates were followed at several temperatures spectrophotometrically at 280 and 420 nm. Reducing sugar did not affect water contents, but xylose reduced the T(g) of the solid models. Sugars showed decreasing NEB reactivity in the order xylose > fructose > glucose in every matrix material. The NEB reactivity and temperature dependence of the single sugars varied in different matrices. The NEB rates of the solid models increased at temperatures 10-20 degrees C above the T(g), and nonlinearity was observed in Arrhenius plots in the vicinity of T(g). The temperature dependence of nonenzymatic browning could also be modeled using the WLF equation.
研究了还原糖（果糖、葡萄糖或木糖）以及玻璃化转变对麦芽糊精（MD）、聚乙烯吡咯烷酮（PVP）和水体系中非酶褐变（NEB）速率的影响。使用差示扫描量热法（DSC）测定玻璃化转变温度（T(g)）。采用重量法测定水分含量，并在几个温度下于280和420 nm处通过分光光度法跟踪NEB速率。还原糖不影响水分含量，但木糖降低了固体模型的T(g)。在每种基质材料中，糖类的NEB反应活性按木糖>果糖>葡萄糖的顺序降低。单糖的NEB反应活性和温度依赖性在不同基质中有所不同。固体模型的NEB速率在高于T(g) 10 - 20摄氏度的温度下增加，并且在T(g)附近的阿伦尼乌斯图中观察到非线性。非酶褐变的温度依赖性也可以使用WLF方程进行建模。
