Abstract This paper presents a novel system able to determine in touchless conditions some rheological properties of bread dough, by application of a force driven by a short air-jet impulse, and the concomitant surface displacement measurement by a laser interferometer. In this work, it is shown that in the FPD (Food Puff Device) is based on the displacement measurement due to an air jet by a laser interferometer test, a “softening” of the bread dough along the kneading process is observed, although it is well known that the bread dough gets strengthened by the kneading. This paradox is explained by the fact that, during the kneading, not only the dough become smooth and elastic, but a certain air amount is incorporated in the form of small air bubbles. FPD provides an empirical short time rheology test exciting the time scales linked to the air bubbles entrapped in the dough, so that the surface displacement is mainly due to the dough aeration. Demonstrating a good sensitivity to the air content, the FPD test seems a relevant method to follow the kneading process, in the aim of developing a tractable and efficient supervision tool. The bulk properties of the dough are also measured by a conventional creep recovery test in a rotational rheometer. An attempt of modelling the viscoelastic behavior in FPD treated like a creep-recovery test is proposed here, to provide some insights in the baking monitoring.

中文翻译：

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空气喷射脉冲系统在揉捏过程中对面包面团充气的评估

摘要 本文提出了一种新系统，能够在非接触条件下通过施加由短喷气脉冲驱动的力以及激光干涉仪测量伴随的表面位移来确定面包面团的一些流变特性。在这项工作中，表明在 FPD（Food Puff Device）中，基于激光干涉仪测试的空气喷射引起的位移测量，观察到面包面团在揉捏过程中的“软化”，尽管它众所周知，面团通过揉面得到加强。这个悖论的解释是，在揉捏过程中，不仅面团变得光滑有弹性，而且一定量的空气以小气泡的形式加入。FPD 提供了一种经验性的短时间流变测试，激发了与面团中夹带的气泡相关的时间尺度，因此表面位移主要是由于面团充气。FPD 测试对空气含量表现出良好的敏感性，似乎是跟踪捏合过程的相关方法，旨在开发易于处理且有效的监督工具。面团的整体特性也通过旋转流变仪中的常规蠕变恢复测试来测量。这里建议尝试对 FPD 中的粘弹性行为进行建模，就像蠕变恢复测试一样，以提供一些对烘焙监测的见解。FPD 测试似乎是遵循捏合过程的相关方法，旨在开发易于处理且有效的监督工具。面团的整体特性也通过旋转流变仪中的常规蠕变恢复测试来测量。这里建议尝试对 FPD 中的粘弹性行为进行建模，就像蠕变恢复测试一样，以提供一些对烘焙监测的见解。FPD 测试似乎是遵循捏合过程的相关方法，旨在开发易于处理且有效的监督工具。面团的整体特性也通过旋转流变仪中的常规蠕变恢复测试来测量。这里建议尝试对 FPD 中的粘弹性行为进行建模，就像蠕变恢复测试一样，以提供一些对烘焙监测的见解。