HI all of you as it is my first post here
My brothers girlfriend who's studiying high-level biology is currently working on bacterias (dont ask me what exactly .... i didn't understand everything....), so i asked her a couple of things about molds, contamination, and sterilisation.
One of her response surprised me a bit compared to what is said over the net about sterilization time :
She told me that when steam was coming out of the safety valve of my pressure cooker, the temp inside was at 130?c (266?F)
AT this temp, she said that 3 to 5 minutes are sufficient to complete sterilization.
I decided to give it a try:
i PC'd ten jars (in 2 times) following this method:when steam was coming out the PC i waited 5 minutes and then shut the fire. I then let them cool the usual way, without precipitation.
I innoculate day after. All with same strain but 6 with end of an older syringe, and 4 with brand new one.
On the 6, 4 have colonized normally (fully at innoc+3weeks 1/2 (yep it is a bit cold in my place, slows growth a bit :(( )
The other 2 didnt colonize at all (i suspected them to be too wet but...)
On the 4 , 3 didnt colonize (also maybe too wet) and one contamed early (after 1-2 weeks).
So on 10 jars, 4 went to the end, one started but failed and 5 were lost.
Were they contamed or were they too wet (when i say wet , i should say a bit muddy) who knows...
My opinion is that maybe 15 mins are Ok to sterilize my jars.
I'll try soon.
DO you think this is real short time???
DO you all sterilize for 45-60 min (what i used to do)??
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Duss69
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Support the FSRE
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Depending on the altitude level at wich you live, most people pressure cook PF style jars at 15 psi for at least 30 min.
Make sure to put tape or foil over the holes in the lids.
Make sure to not overfill with water, the level of the water in the pressure cooker should be below the bottom of the metal lids.
Also Do not use the coarse type of vermiculite, unless you tweak the water content in each jar.
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