How to sterilize wood chips? | Mushroom cultivation | Biobritte mushroom center How to sterilize wood chips?  Preparing the substrate Let the wood chips soak in cold water overnight (12-18h).  Use as much water until all the chips are floating. Put the soaked wood chips into a sieve and let drain for around 15 minutes.  In the meantime put all dry ingredients (sawdust, rye brain, and gypsum) into the mixing container and mix very well.  After the dry ingredients are mixed add the soaked wood chips and mix the substrate again. Finally, add the water and mix it again very well. Mixing proportion For filling of 1 autoclave bag (please use original Unicorn bags Type 14# for wood substrates) you will need 368g wood chips, 735 g saw dust large, 31 g gypsum, 200 g rye bran, and 950 ml water. This will produce approximately 2,5 kg substrate. Sterilization time: about 3 – 4 hours. Filling bags with the substrate Roll down the autoclave bag about 10 cm and pour in 2.5 kg of the wood substrate mi