4 indicators to achieve fermentation accuracy! Testing bacterial cells, controlling dissolved oxygen, determining endpoint... all the dry goods are here
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- Issue Time
- Oct 17,2025
Summary
How to evaluate the accuracy of fermentation? You can refer to the following indicators.

The first level: precise control of process parameters
For example, precise temperature control: Temperature is one of the key factors affecting the fermentation process. Different fermentation strains and stages have their suitable temperature ranges.
For example, yeast has a better fermentation effect at around 25 ℃ -30 ℃. If the temperature is too high, the yeast will become inactive, while if the temperature is too low, the fermentation rate will slow down.
For example, precise control of dissolved oxygen concentration: for aerobic fermentation, the supply of dissolved oxygen is crucial. Insufficient dissolved oxygen concentration can limit the growth and metabolism of microorganisms, while excessive dissolved oxygen concentration may lead to oxidative damage.

Second level: Accurate monitoring of microbial growth status
For example, precise control of bacterial concentration: Bacterial concentration reflects the growth of microorganisms and can be measured by methods such as optical density, dry weight, and cell counting.
During the fermentation process, it is necessary to regularly monitor changes in bacterial concentration to understand the growth stage and rate of microorganisms.
For example, precise control of metabolite concentration: The purpose of fermentation is to produce specific metabolites, so it is necessary to monitor the concentration of metabolites.
Qualitative and quantitative analysis of metabolites can be performed using analytical methods such as chromatography, spectroscopy, and enzymatic analysis.

The third level: precise control of the fermentation process
For example, accurately determining the endpoint of fermentation: Accurately determining the endpoint of fermentation is very important. Ending fermentation too early may lead to insufficient product yield, while ending fermentation too late may affect the quality and stability of the product.
There are various methods to determine the endpoint of fermentation, such as changes in pH value, increases in product concentration, and decreases in gas production.

The fourth level: precise control of fermentation product quality
For example, precise control of product purity: For products produced by fermentation, it is necessary to test whether their purity meets the requirements.
For example, in the field of biopharmaceuticals, protein drugs produced by fermentation need to undergo purity testing to ensure the safety and efficacy of the drugs.
Purity testing can be performed using methods such as high-performance liquid chromatography and electrophoresis to analyze the impurity content in the product.