The purpose of passing steam through the culture media in a bioreactor is to

The correct option is A sterilise the culture media
Bioreactors are large vessels that are used for large scale culturing of cells (plant, animal or microbial) to obtain specific gene products for commercial use.

It provides optimum growth conditions, such as, temperature, pH, nutrients, oxygen (aerobic bioreactors), etc., for achieving higher yields of the desired gene product.

One of the most commonly used bioreactors, which ensure thorough mixing of culture, are stirred type bioreactors.

The purpose of passing steam through the culture medium is to kill the microbes that might be present in it. The total heat content present in the steam is enough to sterilise the medium prior inoculation to avoid unnecessary contamination.


The excess heat generated in the culture media due to ongoing metabolic reactions is overcome by external cooling jackets. The water present between the jacket and the vessel absorbs heat and optimizes the temperature.

Maintenance of pH in a bioreactor is crucial for cell growth which is done by addition of buffers.