Measurement of thermophysical properties of various starches in the freezing processes
1988
Kong, J.Y. (National Fisheries Univ. of Pusan, Pusan (Korea R.). Dept. of Biological Science) | Kim, M.Y. (National Fisheries Univ. of Pusan, Pusan (Korea R.). Dept. of Refrigeration Engineering) | Cheong, J.W. (Korea Food Research Institute, Banwol (Korea R.))
The freezing point (Tf), latent heat of freezing (delta Hf) and kinetic constant of freezing (Kf) were determined from DSC thermogram at coaling rate -2.5deg C/min- -10.0deg C/min. The freezing point of various starches decreased with an increase in cooling rate, and that of whole starches were lower than defatted starches. Changes of the latent heat of freezing was not observed at above cooling rate -2.5deg C/min. The latent heat of freezing (delta Hf) could be deduced as a function of water content (W). Delta Hf=0.700W-13.048, (Kcal/Kg) (35 %=70 %). In the water content range 35-90 (wt %), the activation energy of various starches in freezing process was determined 126-270 Kcal/mol
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