Home | Community | Message Board


This site includes paid links. Please support our sponsors.


Welcome to the Shroomery Message Board! You are experiencing a small sample of what the site has to offer. Please login or register to post messages and view our exclusive members-only content. You'll gain access to additional forums, file attachments, board customizations, encrypted private messages, and much more!

Shop: Left Coast Kratom Buy Kratom Extract   North Spore Bulk Substrate   OlympusMyco.com No Unicorns Hereβ€”Just Quality Bags That Work   MagicBag.co Certified Organic All-In-One Grow Bags   PhytoExtractum Buy Bali Kratom Powder

Jump to first unread post Pages: 1
Offlinetrippleblack
Stranger
 User Gallery
Registered: 12/01/19
Posts: 391
Last seen: 2 months, 11 days
is it pointless to bleed the autoclave of air pockets
    #28380261 - 06/30/23 02:37 PM (1 year, 6 months ago)

Question..

is it pointless to bleed the  autoclave of air pockets if the bags or containers within the cooker has water?

I can save 45+ minutes by closing the pressure valve instantly instead of letting steam build up, releasing, and waiting for another build up. 

it's standard practice to let pressure build up in pressure cooker/ autoclave until steam vent continuously for 5 mins, then we should shut valve and let pressure build up, then at 15 psi open valve and vent for another 3 - 5 minutes, then shut it again.

This is suppose to prevent sterilization fails from dry air pockets inside the pressure cooker -since the steam can't penetrate dry pockets.

most of us are using these autoclaves to sterilize containers already filled with water; like grain bags, grain jars, or wet substrate.

Extras: Filter Print Post Top
InvisiblebodhisattaMDiscordReddit
Smurf real estate agent
 User Gallery
Folding@home Statistics
Registered: 04/30/13
Posts: 61,916
Loc: Milky way
Trusted Cultivator
Re: is it pointless to bleed the autoclave of air pockets (moved) [Re: trippleblack] * 1
    #28382140 - 07/02/23 06:54 AM (1 year, 6 months ago)

This thread was moved from Advanced Mycology.

Reason:
This is the basics

And you will get failed sterilization if you don't vent.

Extras: Filter Print Post Top
InvisibleStipe-n CapMDiscord
The Pride of Cucamonga
Male User Gallery

Registered: 08/04/12
Posts: 8,269
Loc: Canada
Trusted Cultivator
Re: is it pointless to bleed the autoclave of air pockets [Re: trippleblack] * 2
    #28382165 - 07/02/23 07:17 AM (1 year, 6 months ago)

Stop trying to "save time", there's no shortcuts with sterility assurance.

Every vessel is filled with gas. Whether it be your pressure cooker, grain jar, or spawn bag all of these vessels are filled both with the material intended for sterilization and trapped gas. When you place the lid on any pc you are now encapsulating that gas.

Venting is required to purge this trapped gas from the unit/vessels while simultaneously replacing it with steam. If you fail to purge the pc/autoclave you're pressurizing the mixed trapped gases which will result in a lower temperature than if you allowed the steam to occupy the vessel alone, via the vent.

Daltons law covers this phenomenon:

Quote:

According to Dalton's law of partial pressures, the total pressure by a mixture of gases is equal to the sum of the partial pressures of each of the constituent gases. The partial pressure is defined as the pressure each gas would exert if it alone occupied the volume of the mixture at the same temperature.

https://www.shroomery.org/forums/showflat.php/Number/27970850#27970850

Extras: Filter Print Post Top
OfflineSirPsycho
Purple Belt in Google-Fu
I'm a teapot User Gallery


Registered: 01/01/20
Posts: 7,340
Loc: Rent free in your head
Last seen: 10 hours, 17 minutes
Trusted Cultivator
Re: is it pointless to bleed the autoclave of air pockets [Re: Stipe-n Cap] * 2
    #28382173 - 07/02/23 07:24 AM (1 year, 6 months ago)

Wait... You want to bring it up to pressure, then vent and bring back up to pressure? Pretty sure the manual on mine says to not remove the weight until back down to atmospheric pressure.

Also, saving 45 mins on the most important step of a 2 month process seems just a touch pointless.


--------------------
:pm:Ask about free prints: Ps tampanesis, subtropicalis, cubensis(ESS) and Pan cyanescens:pm:
Balance in life is like running on ice.

  πŸ…‘πŸ…žπŸ…£πŸ…£πŸ…›πŸ…” πŸ…–πŸ…πŸ…πŸ…–

"Mist your balls and fan your asshole" - Pandaskis, 2023

Extras: Filter Print Post Top
OfflinePandaskis
Eating Bamboo
Male User Gallery


Registered: 03/14/23
Posts: 1,869
Last seen: 8 months, 8 days
Re: is it pointless to bleed the autoclave of air pockets [Re: SirPsycho]
    #28382179 - 07/02/23 07:31 AM (1 year, 6 months ago)

The TCs really jumped on his ass for this one LOL

Edited by Pandaskis (07/02/23 07:34 AM)

Extras: Filter Print Post Top
InvisibleStipe-n CapMDiscord
The Pride of Cucamonga
Male User Gallery

Registered: 08/04/12
Posts: 8,269
Loc: Canada
Trusted Cultivator
Re: is it pointless to bleed the autoclave of air pockets [Re: SirPsycho]
    #28382181 - 07/02/23 07:32 AM (1 year, 6 months ago)

Yeah, that's what the manual says for All American bench sterilizers. It's called pulse evacuating, or something. I personally don't vent that way because I never use the basket. I remove the vent tube as well, the tube gets in the way and is only practical when used alongside the internal basket. Fuck the basket.

OP, just keep your valve open while allowing the steam to realease as the unit  temperature climbs. Start your timer for purge once steam begins to hiss from the valve. I don't trust pulse evacuating with bags, it might be ok but feels like a poor choice.

I vent 75x for 30 mins, everything under that for 15.

Extras: Filter Print Post Top
InvisibleAyePlus
Stony Danza
Male User Gallery

Registered: 12/18/14
Posts: 3,393
Loc: Fairfield, Connecticut
Trusted Cultivator
Re: is it pointless to bleed the autoclave of air pockets [Re: Stipe-n Cap]
    #28382293 - 07/02/23 09:08 AM (1 year, 6 months ago)

I sometime pulse evacuate @  5-7psi for bags, it does shave ~30 minutes off


Close as soon as it starts hissing, Bring to 5, open and drop to 2-3psi then close and repeat  i let it bleed for about 2 minutes in total,


Only worth doing if you’re on a tight schedule imo, i have my cookers on timers and sometimes you have to have it dialed before getting into another project..


I’ve had a few friends who lost whole runs to bacillus because of not venting long enough, seems to be prevalent in the local wheat source (bar ale)


--------------------
Learn about breeding

C10’s agar guide
Good surface conditions = Good pinsets
Read more, post less.
πŸ…‚ πŸ„° πŸ„Ό πŸ„΄  πŸ…ƒ πŸ„΄ πŸ„° πŸ„Ό
πŸ…ƒ πŸ„΄ πŸ„° πŸ„Ό  πŸ„² πŸ„» πŸ„Έ πŸ„½ πŸ„Ά πŸ…† πŸ… πŸ„° πŸ„Ώ

Extras: Filter Print Post Top
Offlinetrippleblack
Stranger
 User Gallery
Registered: 12/01/19
Posts: 391
Last seen: 2 months, 11 days
Re: is it pointless to bleed the autoclave of air pockets [Re: Stipe-n Cap]
    #28382390 - 07/02/23 10:22 AM (1 year, 6 months ago)

Quote:

Stipe-n Cap said:
Stop trying to "save time", there's no shortcuts with sterility assurance.

Every vessel is filled with gas, whether it be your pressure cooker, grain jar, or spawn bag all of these vessels are filled both with the material intended for sterilization and trapped gas. When you place the lid on any pc you are now encapsulating that gas.

Venting is required to purge this trapped gas from the unit/vessels while simultaneously replacing it with steam, if you fail to purge the pc/autoclave you're pressurizing the mixed trapped gases which will result in a lower temperature than if you allowed the steam to occupy the vessel alone, via the vent.

Daltons law covers this phenomenon:

Quote:

According to Dalton's law of partial pressures, the total pressure by a mixture of gases is equal to the sum of the partial pressures of each of the constituent gases. The partial pressure is defined as the pressure each gas would exert if it alone occupied the volume of the mixture at the same temperature.

https://www.shroomery.org/forums/showflat.php/Number/27970850#27970850




i know this is basic stuff.. but i just did it, without understanding it's grave importance or the detailed reason behind it. 

Daltons Law..

thanks.  this is what i was looking for.  I never not vented of course, but was pondering over the possibility.  That thread is absolutely amazing, i missed it.

Extras: Filter Print Post Top
InvisibleStipe-n CapMDiscord
The Pride of Cucamonga
Male User Gallery

Registered: 08/04/12
Posts: 8,269
Loc: Canada
Trusted Cultivator
Re: is it pointless to bleed the autoclave of air pockets [Re: trippleblack]
    #28382396 - 07/02/23 10:25 AM (1 year, 6 months ago)

One of my biggest mistakes as a new grower was to attempt shaving time off the process by not venting. The resulting plague of bacteria was biblical, but that blunder taught me a lot.

Extras: Filter Print Post Top
InvisiblebodhisattaMDiscordReddit
Smurf real estate agent
 User Gallery
Folding@home Statistics
Registered: 04/30/13
Posts: 61,916
Loc: Milky way
Trusted Cultivator
Re: is it pointless to bleed the autoclave of air pockets [Re: Stipe-n Cap] * 1
    #28382412 - 07/02/23 10:43 AM (1 year, 6 months ago)

Quote:

Stipe-n Cap said:
Yeah, that's what the manual says for All American bench sterilizers. It's called pulse evacuating, or something. I personally don't vent that way because I never use the basket. I remove the vent tube as well, the tube gets in the way and is only practical when used alongside the internal basket. Fuck the basket.

OP, just keep your valve open while allowing the steam to realease as the unit  temperature climbs. Start your timer for purge once steam begins to hiss from the valve. I don't trust pulse evacuating with bags, it might be ok but feels like a poor choice.

I vent 75x for 30 mins, everything under that for 15.



I called AA and spoke with an engineer and explained what mushrooms growers are trying to do and he agreed removing the tube and basket was appropriate.


https://www.shroomery.org/forums/showflat.php/Number/24180711/vc/1#24180711

Also here's my supplemental reading material on the matter

Extras: Filter Print Post Top
InvisibleStipe-n CapMDiscord
The Pride of Cucamonga
Male User Gallery

Registered: 08/04/12
Posts: 8,269
Loc: Canada
Trusted Cultivator
Re: is it pointless to bleed the autoclave of air pockets [Re: bodhisatta]
    #28382424 - 07/02/23 10:52 AM (1 year, 6 months ago)

Sweet :rockon:

Extras: Filter Print Post Top
Jump to top Pages: 1

Shop: Left Coast Kratom Buy Kratom Extract   North Spore Bulk Substrate   OlympusMyco.com No Unicorns Hereβ€”Just Quality Bags That Work   MagicBag.co Certified Organic All-In-One Grow Bags   PhytoExtractum Buy Bali Kratom Powder


Similar ThreadsPosterViewsRepliesLast post
* STAL techniques, or Eggs in various Baskets. Dickhead 352 5 08/25/09 07:49 PM
by Dickhead
* Crazy electric autoclave buy
( 1 2 all )
Freakdaddy 3,381 38 04/05/10 06:16 AM
by kurshiukas
* S. Cal area walk in AUTOCLAVE agar 2,112 12 06/15/07 02:09 PM
by Jeremy_Davis
* Pressure cooker vs Stovetop Autoclave... HELP! galamb 13,690 8 10/29/12 07:40 PM
by tropicalfrenzy
* Moving away from baskets and beds Buckeye Oysters 1,751 16 12/17/08 03:22 PM
by Omnicracker
* An alternative to using an autoclave or pressure cooker Brainiac 6,642 9 05/21/06 02:18 PM
by fastfred
* autoclav modding ohmatic 1,570 4 12/01/04 06:05 AM
by ohmatic
* Straw Basket is now Pinning (w/ Pics)!
( 1 2 3 4 all )
sp4cem0nkey 7,295 68 03/27/10 09:52 AM
by sp4cem0nkey

Extra information
You cannot start new topics / You cannot reply to topics
HTML is disabled / BBCode is enabled
Moderator: Shroomism, george castanza, RogerRabbit, veggie, mushboy, fahtster, LogicaL Chaos, 13shrooms, hamloaf, cronicr, Stipe-n Cap, Pastywhyte, bodhisatta, Tormato, Land Trout, A.k.a
310 topic views. 30 members, 120 guests and 32 web crawlers are browsing this forum.
[ Show Images Only | Sort by Score | Print Topic ]
Search this thread:

Copyright 1997-2025 Mind Media. Some rights reserved.

Generated in 0.023 seconds spending 0.004 seconds on 12 queries.