A fed-batch process is a
In batch fermentation, microorganisms are inoculated to a fixed volume of medium in a bioreactor. With microbial growth, the nutrients are gradually consumed and byproducts accumulate. Therefore the culture environment is continuously changing. The broth is removed at the end of the run. Batch fermentation is a closed culture system because a limited amount of optimized and sterilized medium is added in the fermenter.
Fed-batch fermentation is a modified version of batch fermentation.
Microorganisms are inoculated and grown under batch regime for a certain amount of time, then nutrients are added to the bioreactor in increments throughout the remaining duration of fermentation to feed them. The entire culture suspension is removed at the end of each run. Hence, it is a partially open system.
Continuous fermentation is an open system of fermentation which runs for an indefinite amount of time. In this method, fresh nutrient medium is added continuously into the bioreactor, and at the same time an equivalent amount of used medium is withdrawn for the product recovery.