TY - JOUR
T1 - Enthalpy-entropy compensation and water transfer mechanism in osmotically dehydrated agar gel
AU - Flores-Andrade, Enrique
AU - Beristain, Cesar I.
AU - Vernon-Carter, Eduardo J.
AU - Gutiérrez, Gustavo F.
AU - Azuara, Ebner
N1 - Funding Information:
The authors acknowledge the support received by CON-ACYT-Mex., project 48061, 84287, 25773, and IPN-SIP. E. Flores-Andrade thanks CONACYT for his study grant.
PY - 2009/9
Y1 - 2009/9
N2 - Enthalpy-entropy compensation and water transfer in osmotically dehydrated agar gel were studied by carrying out experiments at 30, 40, and 50°C in a 60% (w/w) sucrose solution. An additional experiment was carried out at the isokinetic temperature (TB = 14°C) to confirm the physical meaning of TB. When osmotic dehydration (OD) was carried out at the isokinetic temperature, the diffusion coefficient remained constant (≈ 0.54×10-10 m2/s) during the entire process and the weight loss reached a limit (≈ 0.277g/g) when the process was performed at TB. Leffler's criterion indicated that diffusion mechanism was entropically controlled given the internal resistance developed during OD. Results were confirmed by the linear relationship found between the relaxation time and entropy variation according to the Adam and Gibbs equation.
AB - Enthalpy-entropy compensation and water transfer in osmotically dehydrated agar gel were studied by carrying out experiments at 30, 40, and 50°C in a 60% (w/w) sucrose solution. An additional experiment was carried out at the isokinetic temperature (TB = 14°C) to confirm the physical meaning of TB. When osmotic dehydration (OD) was carried out at the isokinetic temperature, the diffusion coefficient remained constant (≈ 0.54×10-10 m2/s) during the entire process and the weight loss reached a limit (≈ 0.277g/g) when the process was performed at TB. Leffler's criterion indicated that diffusion mechanism was entropically controlled given the internal resistance developed during OD. Results were confirmed by the linear relationship found between the relaxation time and entropy variation according to the Adam and Gibbs equation.
KW - Agar gel
KW - Enthalpy-entropy compensation
KW - Moisture diffusion
KW - Osmotic dehydration
UR - http://www.scopus.com/inward/record.url?scp=70349868340&partnerID=8YFLogxK
U2 - 10.1080/07373930902904921
DO - 10.1080/07373930902904921
M3 - Artículo
SN - 0737-3937
VL - 27
SP - 999
EP - 1009
JO - Drying Technology
JF - Drying Technology
IS - 9
ER -