Pasteurization can be a pain in the ass. If you're one of the lucky ones, you've got plenty of free time and no prying eyes (especially little ones), so you can make a mess.
I have very little free time. I was desperate for an easy way to pasteurize bulk substrates. I have an oven, but in the summer it heats the house up so much, and is pretty inefficient. Also, I'm concerned with the substrate drying out.
That's when I decided that I would try to pasteurize in an Instant Pot. Everyone said I was daft to build a castle on a swamp, but I built one all the same - just to show them. It sank into the swamp.
Ah wait. I was hopeful that the Instant Pot pasteurization would be an easy fix. The process sure was easy - turkey bag full of spawn, closed up, plopped into the Instant Pot with the little riser to keep it off the bottom. Steam pasteurization at presumably 160 degrees Fahrenheit for an hour and a half.
It failed. Cobweb mold everywhere. Was it the pasteurization, or was the sub too wet? Not enough air?
PFJammer gave the first indication that my pasteurization time was lacking. So I bumped it up to two hours.
And I can happily report success.
Another upside of the Instant Pot is that it is a well-insulated container. This means that the energy expenditure for running the Instant Pot is low. Once it gets up to temperature, maintaining the temperature is very easy. I may in-line a gauge to figure out exactly how much power it's drawing over the two hours. I suspect that it is pretty low. Perhaps even in in the range of boiling water for a cooler-style pasteurization.
Lastly - this is safe! No need to worry about monitoring the oven (these accidents do happen). The Instant Pot is smart - it shuts itself off when it senses failure.
This process is very easy. I highly recommend it. Easy - efficient - safe. For under $200. I know that's a fair amount of money to some. But the Instant Pot is just generally a useful thing to own. 10/10 - would buy again.