ABSTRACT
The most prominent substrate is glucose, and its oxidation
can be described as
C6H12O6 þ 6O2 ! 6CO2 þ 6H2Oþ 2870 kJ (1)
The respiration rate is usually maximal at moderate
temperatures between 20C and 30C, but declines considerably with temperature decrease to around 0C, depending on genus, species, and even cultivar.
Increasing the partial pressure of CO2, or decreasing the
partial pressure of O2, will also inhibit the reaction illu-
strated in Eq. 1 and reduce the respiration rate. However,
if the O2 concentration becomes too low, the respiration
metabolism may be inhibited completely and fermenta-
tion will take place. This is a metabolic route that has
ethanol as an end product and that, from the energetic
point of view, is much less efficient.
