摘要
蛋白质水凝胶中水状态的研究有利于深入了解蛋白质水凝胶的结构、性能与功能.本文选用鸡蛋蛋清作为蛋白质水凝胶样品，利用同步热分析仪，在10K/min的升温过程中，分别研究密封坩埚内蛋清和蒸馏水的热流Φ、相对质量m/m0随温度T的变化情况.经过研究分析得到了如下结果：1）蛋清和蒸馏水在-50℃～50℃温度范围内的升温过程中都出现了熔化现象，而且实验结果具有很好的重复性，蛋清发生的变化为可逆变化，并且与热历史无关.2）蛋清和蒸馏水的熔化峰的峰形在高温区表现了很好的相似性，在低温区（-15～0℃）明显不同，表明蛋清和蒸馏水在熔化初始时，各自所对应的熔化行为并不相同，但是在峰值温度以上温区内，二者的熔化行为是相同的.3）凝胶网状结构影响蛋清中可冻结水晶粒尺寸的分布，该分布不同于蒸馏水中晶粒分布，使得蛋清的熔化峰出现的温度低于蒸馏水的熔化峰温，并且熔化初始时的行为与蒸馏水不同.4）利用DSC方法通过熔化峰的吸热量计算蛋白质水凝胶中可冻结水含量的方法存在系统误差，但偶然误差小.
The study of water status in protein hydrogel will help to understand the structure, performance and functionality of protein hydrogel deeply. The egg white is used for protein hydrogel sample in this paper, then simultaneous thermal analyzer is employed to study egg white samples and distilled samples water in sealed crucible in the 10K/min heating process respectively, and the heat flowΦ and the relative quality m/m0 changes with temperature T of which are gained. The following results are gotten after the analysis. 1） Both Egg white and distilled water have the melting phenomena in the heating process in the temperature range of -50℃~50℃; Moreover, the experiment results have good repeatability, which shows that the change of egg white is a reversible process without the thermal history. 2）The melting peaks of egg white and distilled water in the high temperature side show good similarity, however the peaks are significantly different at low temperature （-15~0℃）, which show that the melting mechanism of egg white and distilled water is different at the initial melting and the same above the melting peak temperature. 3）The gel network structure in egg white influence on the distribution of the size of freezing water grain different from the grains distribution of the distilled water, which causes that the melting temperature of egg white is lower than distilled water’s and the melting behavior in the initial side is also different from distilled water’s. 4） The analysis results show that the method according to the absorption heat of the melting peak by DSC to calculate the content of the freezing water in protein hydrogel has a systemic error, however, the accidental error of which is smaller.
出处
《伊犁师范学院学报（自然科学版）》
2014年第2期31-34,44,共5页
Journal of Yili Normal University：Natural Science Edition
基金
伊犁师范学院重点学科开放课题基金(2012ZDXK28)
新疆凝聚态相变与微结构实验室开放课题基金(XJDX0912-2012-05)
