MEASUREMENT OF HEAT-CAPACITY FOR BORAGE SEEDS BY DIFFERENTIAL SCANNING CALORIMETRY

Specific heat capacity of borage seeds was determined by differential scanning calorimetry (DSC) in the temperature range of 5 to 80C and mo isture content range of 0.47 to 30.31% wet basis. The specific heat ra nged from 0.57 to 2.48 kJ/kgK. A multiple regression model with intera ction terms correlated well the specific heat to temperature (T) and m oisture content (M). It was found that the interaction terms TM and T M-2 were significant (alpha = 0.01) and thus were included in the mod el, and the term MT-2 was insignificant. Effect of measurement techni ques with DSC were also investigated in this study to ensure that true specific heat values were obtained. Seal condition of the sample hold ers during DSC measurement had considerable effect on the specific hea t of borage seeds. The difference between the specific hear of sealed and unsealed samples increased as seed moisture content increased, esp ecially at higher temperatures. For the measurement of the specific he at of borage seeds by DSC in the above-mentioned temperature and moist ure content ranges, an average of 5.75% deviation was found between th e measurement with and without blank compensation.