Correct sterilization for mushroom cultivation can be the difference in having a 50% chance of contamination or a 0% to 5% chance of contamination.
You could not worry about sterilization at all and your mushroom would still grow effectively 30% of the time, however by understanding a few important things you can reduce it down to 0% to 5%.
You need to understand that there are spores from competing fungi floating around all around you. They are also all over you and in the air you breath all day.
So, any time you take some thing that is sterile and expose it to normal air you risk some type of spore getting into your sterile product.
This can be reduce by only opening the container for a few seconds or just long enough to make the transfer then immediately closing it again.
In this podcast we also get into many more techniques you can use to include using a laminar flow hood, still air box, 70% alcohol, gloves, masks, and more.
You can also check out an article we have written that expands even further on the information discussed in the podcast:
https://curativemushrooms.com/sterilization-for-mushroom-cultivation