Thermal Analysis of Foods

许多食品可以通过热分析分析某些效果和特性，其中更重要的是用斑点标记。

For this experiment, seeds available commercially from a health food store were used.

Conditions

测量单元格：DSC20

Pan: Aluminum standard, 40 µl, hermetically sealed

Reference: About 40 µl in a sealed pan

样品制备：磨碎种子，在pH 4.5下进行水性萃取，离心，并丢弃上清液。残留物在pH 8.5处进行重新提取，将上清液在真空下蒸发，直到获得干燥物质含量为止。

DSC测量：以5 k/min的速度从30°C到110°C进行加热

Interpretation

四个vegetable proteins在未经处理的状态下研究了不同类型的类型。四个曲线中的每一个显示在72°C和100°C之间的吸热峰，这是蛋白质变性的典型特征。在热稳定性和蛋白质变性的焓中可以看到差异。

所有样品以及蛋白质浓度的样品重量都是可比的。因此，峰积分直接与特定反应焓对应。

用拼写观察到最高的温度灵敏度，这也具有最大的变性焓。小麦蛋白已经在86°C下在很大程度上经历了变性，此时，大豆蛋白在主机上保持完整，并且在88°C下仅在任何显着程度上具有变性。

Grain and oilseed proteins have enthalpies of denaturation within a range of 3-10 J/g protein. The enthalpy changes with respect to the protein phase. Thus in the native condition of a grain or oilseed the enthalpy of denaturation is lower than when it has been dissolved in aqueous solution.

DSC measurement of denatured protein fraction in processed samples of protein is of better quality if the enthalpy of denaturation of native protein is higher.

The heating rate can be freely selected with DSC which could improve the measurement as well as the detection of the reactions. With a higher rate of heating, the detected signal becomes larger with a larger measured peak. The peak area calculated remains the same under the same conditions of reaction. However, if the rate of heating is high the reaction occurs at elevated temperatures.

DSC可以鉴定植物蛋白，但在实践中不可能广泛使用，并且由于反应焓因蛋白质类型和生长条件而异，因此也更加困难。因此，当评估变性程度时，必须使用天然蛋白质形式的参考。

DSC曲线提供了每个蛋白质样品的指纹，这是馏分中蛋白质状况的特征。

Evaluation

Conclusion

这些测量说明了DSCcan be used to analyze any product that contains protein. This is more applicable to animal proteins because of their higher concentration of protein (in animal muscle), the greater sensitivity of measurement and their natural state of occurrence in a watery environment.

该信息已从梅特勒·托莱多（Mettler Toledo）提供的材料中采购，审查和调整。亚博网站下载

有关此消息来源的更多信息，请访问Mettler Toledo-热分析。