Clarifying Bulk Substrates, Pasteurising and Spawning

[Sola]

I was thinking of pasteurising bolk material in a 44 gallon drum with the top cut off. I would have a wood fire underneath it and the material in

a wire mesh basket submersed in the boiling water. I saw a photo of a similar set up in one of stamet's books and thought that this would

probably be the easiest and cheapest method for me. As many of the drums I already have were previously used for storing chemicals I would buy a new, unused one.

So basically is it necessary to have the pressure one would get from a proper pressure cooker? How long would I have to leave the material submersed

in the boiling water? And do people think this is really a viable option? As I saw it in stamet's book I thought it would be alright but no doubt some of you

have some thoughts or ideas that may be of use.

Thanks

Sola

[Amazonian]

Hey sola. If you are just pasteurizing, then there is no need to boil the water. I followed the instructions in the opening post and got fantastic results. I have the Stamlets book and know the photo you are referring to. That is one way to do it, but from what i read in the opening post on Pasteurization, you don't want to boil the water.

Heres an extract from the OP to refresh your memory...

 

Pasteurising - This is the process of heating a media to between 71°C and 82°C (160-180°F). Pasteurisation is carried out for a prolonged time (minimum of 1 hour) and is supposed to kill only heat susceptible organisms and their spores, as opposed to sterilisation which works at a temperature of 121°C (250°F) and is supposed to kill all organisms.The beneficial micro - organisms (mainly bacteria) that are left alive when pasteurising, guard the substrate against other contaminants, for instance different moulds, but don't affect the growth of mushroom mycelium.

Pasteurisation is used for bulk substrates like straw, dung, composts and wood chips - and casing materials.

If you sterilise a bulk substrate you leave it more open to contamination and therefore have to practice sterile techniques when spawning, therefore sterilisation of a bulk substrate isn't recommended!.. /END

Mine was done in oven bags in an esky and i added the water at the correct temperature and put the lid on and waited like an hour. I did this a few times.

I hope this was helpful .Good luck with your ventures. Mushroom growing is very rewarding.

Edited May 10, 2011 by Amazonian

[Sola]

Thanks amazonian, I'd forgotten that since I read it some time ago. It would be really difficult to keep the water boiling anyway.

Unfortunately I don't have an esky but it is something I've been meaning to get. Mine was lost/ stolen years ago and I haven't replaced it.

It may sound strange but the 44 gallon drum may actually be easier to source where I am, plus there's definitely no shortage of wood.

Thanks again for reminding me, can't wait to get the mycelium up and running.

Cheers

[Gunter]

good bulk substrate recipe

1:1:1

ground coir:ground corncob:alfalfa cubes w/lime and gypsum

this can be pasteurized without problems of contams

great for monotubs

Don't substitute alfalfa from bales or pellets.

Edited November 19, 2011 by Gunter

[Pablo]

Such an informative post, has cleared up some questions I had about spawning and bulk substrate. I just one thing I don't understand is the casing step. What purpose does this serve?

[satyr]

Such an informative post, has cleared up some questions I had about spawning and bulk substrate. I just one thing I don't understand is the casing step. What purpose does this serve?

 

The casing will provide the micro climate for pin development....for more info http://www.shroomery.org/forums/showflat.php/Number/3290155#3290155

[Bigred]

to case or not to case imho i like to late case just as the hyphal knots form i seem to get more per flush

[TheDudeAbides]

Great thread. One question I have is; what's the best method for inoculation? I'm struggling to find any information on how best to go about sterile inoculation.