This happens two ways. The first is that there is to much water in the pot and the boiling water can slosh into the jars. Then the water builds up in the lower part of the jar and the soaked substrate will not colonize correctly (or not at all - and stall) The second way is water dripping from the top of the pot down onto the jars. If you use regular canning lids, these do not seal the jar and water dripping down can go into the jars.
In the first incident - use a safe amount of water so that sloshing into jars doesn't happen.
In the second incident - cover the lids with tin foil to ward off dripping water.
In the beginning, All the subsequent letters from the myco customers with problems had to do with the pint jar. It was causing lots of trouble. 1/2 pints seemed immune to problems.
I already knew of the pint "trouble". So I dropped the tek. The "trouble" was "premature" fruiting (like thats bad?). What would happen, is that Pint sized cakes would commonly have the tendancy to begin putting out primordia and screaming to be released from in vitro BEFORE complete colonization of the cake, mainly caused by not enough spore solution delivered all around making for an uneven colonization.
So there you would have a tear jerking disaster on your hands; primordia all dressed up with no place to go. Because, birthing the cake would expose the exposed uncolonized cake surface (which sometimes is about half the surface) and you will not only have shrooms growing, but plenty of contamination (hence the absolutely ingenious MMGG technique of branding the cake.)
What is causing this is that the vermiculite in the mixture is the fruiting catalyst which stimulates fruiting whether the food is used up or not. The fruiting is clearly related to a food threshold and nothing to do with CO2 or oxygen - temperatures ect. And this is Because these primordia will appear just the same in a jar in which the lid has been on tight since the get go. (NO OXYGEN) strange but true.
To see the truth of this in demonstration: Try a pint jar of plain pre cooked (quite wet and soft is the way) brown rice in comparison to an equal pint jar of pf substrate mixture. (you don't have to go to the trouble to do this, but read on and trust PF)
When a pint of plain rice is colonized, and left to sit in vitro, Primordia will not appear and then the jar starts to yellow - die ect. The neglected pint jar of pf substrate will put forth plenty of primordia hot to get it on while in vitro. It is like two completely different substrate mediums but basically it is brown rice.
In these two examples is clearly shown what the pf tek is all about. The vermiculite is the catalyst for fruiting - similar to casing grain (but without the casing tek) - sort of an internal automatic casing.
That is why all of this stuff about casing pf cakes to make them work the best is from people that have no idea about the pf tek and its inner workings.
Psylocybe Fanaticus
Seattle Washington
Decemember 27 1998