Sterilization of Fermentation Media
Sterilization of fermentation media play a important role in fermentation .If the fermentation media is not sterilized properly or we can say if the media gets contaminated it can lead to economic loss.The contamination of media can effect the yield of product,it can change the product or it can effect the growth of fermentation organism.So it is very important to sterilise the fermentation media properly.
There are different techniques used to sterilise different types of media as well as different nutrient supplies used in fermentation .Depending on the necessity the sterilization techniques are used..Fermentation techniques are carried out in Laboratory scale as well as Industrial Scale .
Sterilisation of fermentation media is done by Autoclaving, Boiling, or passing steam through media.The synthetic media can be sterilized in short time where as crude media requires more time for sterilization. Sterilization method used is decided on basis of type and characteristic of media components.
Crude media is more viscose and it may contain spores or highly resistant bacteria so the time required for sterilization is more.Where as crude media contain high sugar content so it should be sterilized properly because if high amount of heat is passed for longer duration of time through media it may caramelise sugar sugar content of media and result in spoilage of media.
The fermentation media which contains substances that can undergo chemical changes as well as degradation due to heat such fermentation media is sterilised by filtration. Some fermentation media contains vitamins,enzymes and volatile components in media get destroyed easily by heat.So such media component should be sterilized using bacteriological filters.
Generally fermentation media is sterilized by autoclaving that is sterilization of media steam under pressure.If fermentation media is in large amount the fermentation batches are passed through heat retention tubes containing jet heaters.So the type of sterilization technique used depends upon type of fermentation media and type of components present in it.