Thermal and Dynamic-Mechanical properties of frozen wheat doughs with added sucrose, NaCl, ascorbic acid, and their mixtures

The effects of sucrose, NaCl, and ascorbic acid on the physical state of wh eat dough at sub-zero temperatures were investigated using Differential Sca nning Calorimetry (DSC) and Dynamic-Mechanical Analysis (DMA). The DSC ther mograms were obtained for annealed samples by scanning from -80 to 10 degre esC at 5 degreesC/min. Added sucrose and NaCl decreased the onset of ice me lting of doughs, and they were found at -26 degreesC. Added sucrose and NaC l increased the relative amount of unfrozen water in doughs, while added as corbic acid had not noticeable effects. DMA measurements were made for anne aled samples at a heating rate of 1 degreesC/min from -150 to 10 degreesC. The loss modulus, G ", of DMA showed an alpha -relaxation (glass transition ), two low temperature relaxations (beta and gamma), and melting of ice in all doughs with added ingredients.