Factors affecting microbial enzyme fermentation

Fermentation engineering is the use of modern fermentation equipment, the use of microbial growth and metabolic activities, optimized cells or modern technologically modified strains for amplified culture and controlled fermentation, to obtain industrialized production of predetermined food or food functional ingredients.

Factors affecting microbial enzyme fermentation

1. Temperature

2. pH

3. Water content

The water content of the substrate should be determined according to the nature of the raw materials (fineness, water holding capacity, etc.), the characteristics of the microorganisms (anaerobic, facultative anaerobic or aerobic), and the conditions of the culture room (temperature, humidity, and ventilation). 

If the water content is high, the porosity of the substrate is reduced, the volume of gas in the substrate and the gas exchange are reduced, it is difficult to ventilate and cool, and the risk of contamination by bacteria is increased; while the water content is low, the substrate expansion is low, and the microorganisms The growth is inhibited. 

In the later stage, the material may be dried out due to the growth and evaporation of microorganisms, which makes it difficult for microorganisms to grow and yields decrease.

4. The effect of oxygen on fermentation

The supply of oxygen is often one of the important limiting factors that determines the success of fermentation in aerobic deep culture. With the wide application of high-yield strains and the adoption of nutrient-rich culture media, microbial enzyme fermentation has higher requirements for oxygen. 

During the vigorous fermentation period, even if the medium is saturated with air, the amount of oxygen stored in it is still very small, and it can generally only maintain normal breathing for 15 to 30 seconds. 

Afterwards, the respiration of microorganisms will be restricted. Therefore, during the growth of organisms, ventilation, stirring or turning are usually used to increase the oxygen transfer.