TY - JOUR
T1 - Analysis of temperature distribution in potato tissue during blanching and its effect on the absolute residual pectin methylesterase activity
AU - González-Martínez, Gerardo
AU - Ahrné, Lília
AU - Gekas, Vassilis
AU - Sjöholm, Ingegerd
PY - 2004
Y1 - 2004
N2 - Dynamic changes in absolute residual PME activity in potato tubers undergoing blanching were analysed with regard to the temperature distribution in the tissue after the treatment. The finite-element technique was used to predict the temperature distribution within the tissue during blanching. The temperature-related behaviour of the enzyme indicated that blanching between 60 and 70 °C induced thermal activation of PME in blanched potatoes. The temperature distribution in the tissue during blanching showed that activation takes place as soon as the tissue reaches an average temperature above 50 °C. However, the temperature dependence of the absolute residual PME activity in the tissue, when blanching at temperatures between 50 and 70 °C, did not follow Arrehenius' law. The degree of PME activity in the blanched tissue was found to depend on the "effective exposure time" to the temperature at which the activation/deactivation of the enzyme takes places. Thermal activation of PME in potato tissue occurred during the first two minutes of blanching. Longer heating times induced rapid deactivation of the enzyme in the tissue.
AB - Dynamic changes in absolute residual PME activity in potato tubers undergoing blanching were analysed with regard to the temperature distribution in the tissue after the treatment. The finite-element technique was used to predict the temperature distribution within the tissue during blanching. The temperature-related behaviour of the enzyme indicated that blanching between 60 and 70 °C induced thermal activation of PME in blanched potatoes. The temperature distribution in the tissue during blanching showed that activation takes place as soon as the tissue reaches an average temperature above 50 °C. However, the temperature dependence of the absolute residual PME activity in the tissue, when blanching at temperatures between 50 and 70 °C, did not follow Arrehenius' law. The degree of PME activity in the blanched tissue was found to depend on the "effective exposure time" to the temperature at which the activation/deactivation of the enzyme takes places. Thermal activation of PME in potato tissue occurred during the first two minutes of blanching. Longer heating times induced rapid deactivation of the enzyme in the tissue.
KW - Absolute PME activity
KW - Blanching
KW - Finite-element analysis
KW - Potato
KW - Temperature distribution
KW - Thermal activation
KW - Thermal activity coefficient
KW - Thermal deactivation rate
U2 - 10.1016/j.jfoodeng.2004.02.003
DO - 10.1016/j.jfoodeng.2004.02.003
M3 - Review
AN - SCOPUS:2942598144
SN - 0260-8774
VL - 65
SP - 433
EP - 441
JO - Journal of Food Engineering
JF - Journal of Food Engineering
IS - 3
ER -