Development of a Novel Phase Transition Measurement Device for Solid Food Materials: Thermal Mechanical Compression Test (TMCT)

摘要

A thermal mechanical compression test (TMCT) device was developed for the mea-surement of glass-rubber transition and surface stickiness properties of food particu-late materials. This device can be used to measure changes in mechanical properties during a glass-rubber transition of solid food materials. The glass-rubber transition temperature (T_g) of various food materials such as sugars, skim-milk powder, fruit-juice powders, whey powders, starch, candy, rice, and nonfood polymers were tested by using this technique, and the data were compared with those from the standard technique. In this TMCT method, about 1g of powder samples or a reasonably sized multiple or single particle grain is subjected to compression force (ca. 10-40 Newtons) and scanned under compression at 30°C/min heating rate. The inflection point is observed at the time of probe displacement when the sample changes from the glassy state to the rubbery state. The results obtained from this technique were comparable with T_g analyzed by a standard differential scanning calorimetry technique.