You wrap it with paper to avoid the collection of vapour and liquid inside plates. If you dont do that they will filled with vapour (water), when you take them out. If they are still wet after taking out, chances for contamination will increase. You can dry glasswares in high temp 120-150 degrees, or more for direct sterilization. If you cover ordinary polythene it will melt down during autoclaving. You can use special autoclavable polybags for this purpose that are available commercially. Glasswares sterilization by heat is also quite enough and convenient, but other plasticwares should be autoclaved.

You wrap it with paper to avoid the collection of vapour and liquid inside plates. If you dont do that they will filled with vapour (water), when you take them out. If they are still wet after taking out, chances for contamination will increase. You can dry glasswares in high temp 120-150 degrees, or more for direct sterilization. If you cover ordinary polythene it will melt down during autoclaving. You can use special autoclavable polybags for this purpose that are available commercially. Glasswares sterilization by heat is also quite enough and convenient, but other plasticwares should be autoclaved.

Better you go for dry heat sterililzation in hot air oven for plates sterilization and for discarding plates conatining the culture you go for wrapping with heat resistant polythene bags which will be available in hi media company

Dear Amit,

I think it is heat of vapours that is required to make the plates hot till a certain degrees. Like in case of liquids, the vapour heat the liquid without comming into contact. The final aim is to increase the temp of anything that is inside, not contacting to vapour.

u have to go for dry heat sterilization instead of autoclaving............

Wraping with paper just to protect the sterilized plates from being contaminated again after you pick them out from autoclaving settings

Actually the steam is needed to build pressure which necessary for lowering the boiling degree of liquids (i.e. water ), consequently you can obtain higher temperature (i.e. more than the boiling degree) e.g. 120 C. Upon such fact the steam has nothing to do with the sterilization process.

Thank u for your valuable points

autoclaving with ur precautions are good as it takes shorter time (15 min )

dry sterilization in electric oven takes 2hr at 120C or 30 min at 180C

i use both prcedures succesfully , good luck