A convenient method to estimate the rate of heat evolution in fermentation



The estimation of heat of fermentation is discussed with reference to experimental data obtained in glucose-, ammonia- and oxygen-limited chemostat cultures of a specific bacterium and also to previous data published by other workers. Whatever the microbial or cultural conditions might be, the heat of fermentation can be easily estimated from TOD (total oxygen demand) measurement, accompanied by the concept of available electrons. If aerobic pathways are dominant in a particular fermentation, the specific rate of heat evolution, QH, can be calculated approximately from QH = Qo2 (−δHo7ast;), where − 7delta;Ho* = 106 kcal/mol O2, using only Qo2 values without the need for either TOD or calorimetric determination.