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Dleucomelas
Mugwump



Registered: 06/15/15
Posts: 13
Loc: Interzone
Last seen: 7 years, 6 months
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Fractional Sterilization
#23390288 - 06/28/16 07:49 AM (7 years, 6 months ago) |
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Been reading about fractional sterilization. I was under the impression that a 3 day cycle of steaming for 60 - 60 -90mins with a 24hr 80F+ incubation in between leads to sterile culture. In my searching on her I found an RR post and was floored when mentioned it depends on the grain! I know this is used to this day for sterilizing sensitive materials that cannot handle pressurized steam. Why is it even a debate if it's proven science?
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Psilosoulful

Registered: 09/05/14
Posts: 7,205
Last seen: 1 year, 1 month
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Re: Fractional Sterilization [Re: Dleucomelas]
#23390293 - 06/28/16 07:50 AM (7 years, 6 months ago) |
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What are you trying to sterilize that can't be placed in a normal PC?
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Dleucomelas
Mugwump



Registered: 06/15/15
Posts: 13
Loc: Interzone
Last seen: 7 years, 6 months
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Quote:
Psilosoulful said: What are you trying to sterilize that can't be placed in a normal PC?
Nothing right now..just wondering why people still think FS doesn't sterilize. I was hoping some really smart experienced people would chime in and share something I haven't read.
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Mad Season
hookers and blackjack



Registered: 09/16/12
Posts: 12,666
Loc: Canada
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Re: Fractional Sterilization [Re: Dleucomelas]
#23390413 - 06/28/16 08:39 AM (7 years, 6 months ago) |
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Endospores.
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foragedfungus



Registered: 09/30/13
Posts: 1,849
Loc: out there
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Re: Fractional Sterilization [Re: Mad Season]
#23390429 - 06/28/16 08:48 AM (7 years, 6 months ago) |
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Dleucomelas
Mugwump



Registered: 06/15/15
Posts: 13
Loc: Interzone
Last seen: 7 years, 6 months
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Quote:
Mad Season said: Endospores.
What about them? The whole point of the method is to allow the 24hr incubation at proper temps to let the heat shocked endospores to go vegetative so they can be killed by successive steaming.
Thanks for the link Forage..hadn't seen that one yet
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Mad Season
hookers and blackjack



Registered: 09/16/12
Posts: 12,666
Loc: Canada
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Re: Fractional Sterilization [Re: Dleucomelas]
#23390487 - 06/28/16 09:13 AM (7 years, 6 months ago) |
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Quote:
Dleucomelas said:
Quote:
Mad Season said: Endospores.
What about them? The whole point of the method is to allow the 24hr incubation at proper temps to let the heat shocked endospores to go vegetative so they can be killed by successive steaming.
Thanks for the link Forage..hadn't seen that one yet 
You do realize endospores are formed as a "safety net" there will always be endospores in endospore forming bacteria.
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Trusted Cultivator said:
clostridum butyricum from brewers grain(rye malt) it's very heat resistant because of the spores. it is responsible for the most part in the rancid smell if you let grains soak too long. it will survive the boil and is why your grains go bad and smell like puke and Greek feet feta if you don't sterilize them after your grain prep.
it forms endospores even culture on anaerobic plates with an abidance of nutrients. as you can see some subset of the population finds it appropriate to form endospores despite not having "bad conditions" as conditions get worse spore formation goes up. I would be nearly positive you end up with more endospores if you do a soak than if you skip a soak, either way these DO get killed by a PC in a sufficient cycle.
also what aloha does (as pasty says) is pressure cook their grains twice. The 2nd run is done for 4 hours. The first run will diminish a lot of bacteria, but the 2nd run should be the one to eventually kill ALMOST all of the endospores. Fractional sterilization to me isn't enough, even if you steam it 5 times over.
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blackout


Registered: 07/16/00
Posts: 5,266
Last seen: 2 months, 25 days
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Re: Fractional Sterilization [Re: Dleucomelas]
#23407057 - 07/03/16 12:59 PM (7 years, 6 months ago) |
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Quote:
Dleucomelas said: Been reading about fractional sterilization. I was under the impression that a 3 day cycle of steaming for 60 - 60 -90mins with a 24hr 80F+ incubation in between leads to sterile culture.
Steaming time would depend on the size of the jar. 24hrs is too long, it's exactly what the inventor warned against. More on that in the link posted earlier.
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Dleucomelas said:In my searching on her I found an RR post and was floored when mentioned it depends on the grain!
I have never seen RR post any info on any fractional sterilization he did, nor any other people who claim it does not work or has a very high failure rate. RR is first to say it rarely works and many people blindly reiterate this, just like people writing textbooks reiterated the 24hr wait time and have probably never attempted it themselves. If you can find any thread where someone actually attempted fractional sterilization I would be very interested, on this or any other site. I see people throw figures around like 99% fail or 90% fail, as though they have conducted tests or at least seen others try, when questioned I don't think I ever got a reply explaining where they got this.
I have never seen a failed attempt at fractional sterilization, as I have never actually seen an attempt at doing why Tyndall was instructing! If they are steaming for 30mins and waiting 24hrs and failed this is doing nothing more than proving that at least his warnings were right.
Quote:
Dleucomelas said:Why is it even a debate if it's proven science?
How do you conclude that its "proven science"?
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Chk
Reverser


Registered: 09/06/13
Posts: 405
Loc: France
Last seen: 5 years, 3 months
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Re: Fractional Sterilization [Re: blackout]
#23407194 - 07/03/16 01:38 PM (7 years, 6 months ago) |
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Also, at any point in time bacteria are forming more or less 10% endospores as a safety, as said above 24h is too much, you could end up with more endospores you started with, the resting time between each steaming/heating is critical.
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Edited by Chk (07/03/16 01:39 PM)
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bodhisatta 
Smurf real estate agent


Registered: 04/30/13
Posts: 61,889
Loc: Milky way
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Re: Fractional Sterilization [Re: Chk]
#23407229 - 07/03/16 01:48 PM (7 years, 6 months ago) |
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Considering we have access to pressure cookers and don't live in Somalia its pretty fucking retarded to not effectively sterilise. Why do more work for less reliable results.
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