Thermal stresses caused by the volume expansion of water during freezing process are often neglected in term of impact on the quality of food. However the state of the art appears quite crude. The aim of this study is to measure the mechanical properties during freezing and thawing of a food model system: a methylcellulose gel or Tylose (75.8% w.c.). The mechanical properties of this gel were measured using two setups: a Dynamic Mechanical Thermal Analysis system in the range of temperatures between [-50, +20]°C with a temperature rate of +/- 2°C. min{sup}(-1) and a traction machine at ambient temperature. Results showed that the gel has an elastic behavior irrespective to the temperature. Its elastic modulus, E', is about 2.0 ± 0.5MPa at +20°C and 22 ± 2GPa at -50°C, whereas its loss modulus, E", is a quarter of E' whatever the temperature. A comparison between ice ratio and mechanical properties is proposed.
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机译：在冻结过程中，由水的体积膨胀引起的热应力通常忽略了对食物质量的影响。然而，艺术的状态似乎很原油。本研究的目的是测量食物模型系统的冷冻和解冻过程中的机械性能：甲基纤维素凝胶或塔雷糖（75.8％w.c.）。使用两种设置测量该凝胶的机械性能：动态机械热分析系统在[-50，+20]℃之间的温度范围内，温度率+/- 2℃。 MIN {SUP}（ - 1）和环境温度下的牵引机。结果表明，凝胶与温度不重要，凝胶具有弹性行为。其弹性模量E'，在-50°C下为+ 20°C和22±2gPa约2.0±0.5MPa，而其损耗模量，E“是E”的四分之一。冰之间的比较提出了比率和机械性能。
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