Arrhenius equation
Japanese: アレニウスの式
An equation mathematically describing the relationship between temperature and reaction rate. The basis for quantitatively predicting how temperature affects fermentation speed.
The Arrhenius equation, proposed by Swedish chemist Svante Arrhenius in 1889, describes the relationship between temperature and reaction rate: k = A·exp(-Ea/RT), showing that rate constant (k) increases exponentially with temperature.
Ea is activation energy—the energy barrier required to initiate a reaction. Enzymes accelerate reactions by lowering Ea. R is the gas constant; T is absolute temperature.
The phenomenon of miso aging 'accelerating in summer, decelerating in winter' can be quantitatively explained by the Arrhenius equation. Why winter-prepared miso ages slowly is also taught by this equation. It provides mathematical backing for traditional brewing wisdom.