Take amino acid fermentation as an example. After inoculation in fermentor, the strain enters a lag period (adjustment period). At this time, it takes a period of time for microorganisms to adapt to the new growth environment, with little change in od value, slow sugar consumption and no acid production.

After the strain entered the logarithmic growth period, the od value increased rapidly, the sugar consumption accelerated obviously, the oxygen consumption increased, and acid production began.

When entering the equilibrium period, a large amount of acid is produced. At this time, the hypoglycemic rate, OD value, oxygen consumption and carbon dioxide excretion were basically stable, and a large number of products were accumulated in the fermentation broth.

After entering the recession period, the blood sugar lowering rate, od value, oxygen consumption, carbon dioxide emission and other indicators all decreased significantly, the product basically stopped growing, and the fermentation entered the countdown. Generally, when the residual sugar is reduced to about 65438 0%, the fermentation is terminated.

Then, in actual production, we must shorten the adjustment period as much as possible and let the microorganisms enter the logarithmic growth period as soon as possible, so as to reduce energy and material consumption, increase microbial biomass and make fermentation enter the product accumulation stage as soon as possible.

At the same time, it is necessary to extend the stable period as much as possible, and quickly accumulate products while rapidly lowering blood sugar. The shorter the fermentation time, the more products are accumulated, the faster the blood sugar is lowered, the higher the utilization rate of fermentation tank, the higher the production efficiency, the lower the energy consumption and the lower the production cost.

Therefore, monitoring the growth curve of microorganisms, using the growth characteristics and product accumulation characteristics of microorganisms in each stage of the curve and taking corresponding measures can obtain more products in a shorter time with less energy and material consumption.