Aerobic respiration rate of Golden Delicious apples as a function of temperature and PO2
G. Andrich, A. Zinnai, S. Balzini, S. Silvestri and R. Fiorentini
Postharvest Biology and Technology. Volume 14, Issue 1, September 1998, Pages 1-9.
1998
บทคัดย่อ
To evaluate the temperature dependence of the constants involved in a
mathematical model relating the aerobic respiration rate of Golden Delicious
apples to the PO2 of the surrounding atmosphere, O2
consumption (rO2) and CO2 production (rCO2)
rates were measured at four temperatures (21, 16, 6 and 1°C)
and five partial pressures of O2 (0, 3, 5, 10 and 21 kPa), while PCO2
was maintained close to zero. The cellular oxidation of the respiratory
substrate was expressed as a function of dissolved O2 by a Michaelis¯Menten-like
equation. The maximum rate of O2 consumption (k2)
increased linearly with temperature and the Michaelis constant KM
decreased according to Arrhenius' equation. The activation energy calculated
for k2 (
E2/R=5097°
K-1) is very close to that found using a different theoretical
approach (E2/R=5447°
K-1). The temperature dependence of these constants made it possible
to individuate a mathematical model able to calculate, as a function of the PO2,
the aerobic respiration rate expected for Golden Delicious apples stored
between 0 and 20°C when a PCO2 value close to zero
was maintained.