无定形食品物理老化过程的数值研究

Numerical Exploration of Physical Aging in Amorphous State Foods

为了估算无定形食品的老化时间,利用数值方法考察了升降温速率和Adam-Gibbs(AG)模型参数对连续升降温无量纲比热容的影响。结果表明,升降温速率会对计算结果产生明显影响,获得的松弛参数要给出是在何种升降温速率下获得的。AG模型参数表现出很强的相关性,如果四个模型参数同时作为自由变量可能会得到不合理结果。通过和实验数据的对照,发现本研究的分析结果对于大致估算AG模型参数有一定指导意义。

In order to estimate the physical aging time of amorphous state foods, numerical method based on the Adam-Gibbs enthalpy relaxation theory was used to observe the effects of cooling/heating rates and model parameters on the normalized specific heat capacities. The results indicated that different cooling and heating rates produce different values of model parameters. The parameters of AG model correlate strongly and at least one parameter can be fixed before the search routine. The results of present study can predict experimental data very well and be used to make rapid estimation of the physical aging time.