A Sterliee technique is of utmost importance in mushroom home cultivation. A pressure cooker is a necessity within this process. A pressure cooker is needed to sterilize your substrates and casing material. Also some supplies like scalpels can be sterilized in a pressure cooker.
When it comes to sterility there is only one rule:
Or it is sterile or it is non-sterile, there is no in-between. If you have any doubts about the sterility consider it to be non-sterile.
For a correct sterilization the pressure within the cooker must be at 15 psi for a certain period. This means it will be about 121 °C within the cooker. No organism will stay alive during such a temperature. The duration of sterilization time depends a lot on the ingredients of the substrate and the volume of it. The specific sterilization time of specific substrates are mentioned in the techniques section.
In a lot of books and other publications there is referred to an autoclave when it comes to sterilization. An autoclave is actually nothing more then just a very expensive pressure cooker. Autoclaves are mostly used in hospitals and professional laboratories and cost thousands of euros. A pressure cooker does the same trick and is already available from 30-40 euro.
It's best to use special filterbags, filterboxes and/or glass jars to sterilize your substrate in. If you decide to use something else always check that it can stand the high pressure and temperatures of a pressure cooker.