Peeled,headed or whole shrimp(Pandalus borealis)was dried in a heat-pump dryer at-2-0℃and 20℃,respectively,and desorption isotherms characterizing the dehydration property of each shrimp sample group were determined...Peeled,headed or whole shrimp(Pandalus borealis)was dried in a heat-pump dryer at-2-0℃and 20℃,respectively,and desorption isotherms characterizing the dehydration property of each shrimp sample group were determined.Desorption isotherms of shrimp handled differently and dried at different temperatures(-2-0℃or 20℃)could be well described by Oswin’s model(X=a(1-a_(w)/a_(w))).The regression model of peeled,headed or whole shrimp was established,which is reliable for predicting the desorption isotherms of shrimp undergoing heat-pump drying.The handling methods of shrimp exhibit measurable influence on desorption isotherms of shrimp,whereas drying temperature(-2-0℃or 20℃)has little influence on the constants of a and n in Oswin’s model,of whole shrimp,even though it has certain influence on these constants of peeled and headed shrimp.For heat-pump drying,headed shrimp may have a better stability than peeled or whole shrimp due to the best stability.展开更多
Moisture sorption isotherms and thermodynamic properties of Camellia oleifera seeds as influenced by oil content were investigated.Moisture desorption and adsorption isotherms of Camellia oleifera seeds,kernels and sh...Moisture sorption isotherms and thermodynamic properties of Camellia oleifera seeds as influenced by oil content were investigated.Moisture desorption and adsorption isotherms of Camellia oleifera seeds,kernels and shells from three varieties were determined using constant temperature and humidity chamber method at different temperatures(10°C,25°C,and 40°C)with water activity ranging from 0.20 to 0.90.Six selected mathematic models were employed to fit the experimental data.The Peleg model gave the best results for both seeds and kernels and Langmuir model was the best for shells.The difference of equilibrium moisture contents at the same water activities during desorption and adsorption indicated the occurrence of hysteresis of adsorption processes and the equilibrium moisture contents tended to decrease with the increasing oil content and temperature.The binding energy and average capacity per unit mass decreased with increasing temperature and oil content.The relationships between water activity and the logarithm of sorption activity showed the capillary porous body characteristics of the seeds.展开更多
文摘Peeled,headed or whole shrimp(Pandalus borealis)was dried in a heat-pump dryer at-2-0℃and 20℃,respectively,and desorption isotherms characterizing the dehydration property of each shrimp sample group were determined.Desorption isotherms of shrimp handled differently and dried at different temperatures(-2-0℃or 20℃)could be well described by Oswin’s model(X=a(1-a_(w)/a_(w))).The regression model of peeled,headed or whole shrimp was established,which is reliable for predicting the desorption isotherms of shrimp undergoing heat-pump drying.The handling methods of shrimp exhibit measurable influence on desorption isotherms of shrimp,whereas drying temperature(-2-0℃or 20℃)has little influence on the constants of a and n in Oswin’s model,of whole shrimp,even though it has certain influence on these constants of peeled and headed shrimp.For heat-pump drying,headed shrimp may have a better stability than peeled or whole shrimp due to the best stability.
基金The authors acknowledge that this work was financially supported by the Gannan Oil Tea Camellia Industry Collaborative Innovation Center(Grant No.YP201610).
文摘Moisture sorption isotherms and thermodynamic properties of Camellia oleifera seeds as influenced by oil content were investigated.Moisture desorption and adsorption isotherms of Camellia oleifera seeds,kernels and shells from three varieties were determined using constant temperature and humidity chamber method at different temperatures(10°C,25°C,and 40°C)with water activity ranging from 0.20 to 0.90.Six selected mathematic models were employed to fit the experimental data.The Peleg model gave the best results for both seeds and kernels and Langmuir model was the best for shells.The difference of equilibrium moisture contents at the same water activities during desorption and adsorption indicated the occurrence of hysteresis of adsorption processes and the equilibrium moisture contents tended to decrease with the increasing oil content and temperature.The binding energy and average capacity per unit mass decreased with increasing temperature and oil content.The relationships between water activity and the logarithm of sorption activity showed the capillary porous body characteristics of the seeds.
