During an actual production run, fermentors are monitored in
real time for temperature, oxygen, pH, and the levels of key nutrients,
such as ammonia and phosphate. This is done because it is
often necessary to alter the conditions in the fermentor as the
fermentation progresses. Computers are used to process environmental
data as the fermentation proceeds and are programmed
to respond by signaling for nutrient additions,
increases in the rate of cooling water, impeller speed or sparger
pressure, or changes in pH or other parameters, at just the right
time to maintain high product yield.