Abstract
On a food heating process, a heat transmission system has been used widely. But, this system involves some intrinsic problems such as overheating, defective sterilization and scorching. Recently, the Joule heating system has been received keen attentions as a sophisticated heating system because of non-scorching, accurate heating and cleanness. However, there are few reports concerning with internal temperature distribution of food materials, especially on Joule heating system. We developed the visualizing method to observe and record the internal temperature distribution as a picture in food materials. The heat sensitive (color changeable) liquid crystal was adapted as a thermo indicator. The visualized results were compared with the data which simulated by a finite element method (FEM) . The visualized results were accurately coincided with the FEM simulations. We demonstrated that heat should be generated uniformly in Joule heating process, if food material was homogenous.
