|
Doctor Mario
πππππ



Registered: 08/07/20
Posts: 1,894
Loc: πΊπΈ
|
Re: BOD's Easy AF how to use your pressure cooker for mycology TEK [Re: vaudvilleviktor]
#27188199 - 02/05/21 03:21 PM (2 years, 11 months ago) |
|
|
Thats normal as long as it stops leaking from when the lock pops up.
|
vaudvilleviktor
Stranger

Registered: 12/11/20
Posts: 91
Last seen: 4 days, 15 hours
|
Re: BOD's Easy AF how to use your pressure cooker for mycology TEK [Re: Doctor Mario]
#27188203 - 02/05/21 03:25 PM (2 years, 11 months ago) |
|
|
cool thanks!
|
Doctor Mario
πππππ



Registered: 08/07/20
Posts: 1,894
Loc: πΊπΈ
|
Re: BOD's Easy AF how to use your pressure cooker for mycology TEK [Re: vaudvilleviktor]
#27188236 - 02/05/21 03:48 PM (2 years, 11 months ago) |
|
|
I didn't clean mine for the first 10 or so uses and it started leaking from the sides. Took the gasket out and wiped it off real good. Problem solved.
|
steelheadwill

Registered: 07/01/17
Posts: 60
Last seen: 5 days, 9 hours
|
Re: BOD's Easy AF how to use your pressure cooker for mycology TEK [Re: bodhisatta]
#27216673 - 02/20/21 12:42 PM (2 years, 11 months ago) |
|
|
Thank you for the info, Especially the explanation of Dalton. I get more satisfaction from following a tek to the T if I know the why, not just the how.
-------------------- I oft find desire more pleasant than acquisition
|
Caleb83838
Stranger
Registered: 05/01/20
Posts: 10
Last seen: 9 months, 15 days
|
Re: BOD's Easy AF how to use your pressure cooker for mycology TEK [Re: bodhisatta]
#27228425 - 02/26/21 10:05 PM (2 years, 10 months ago) |
|
|
Solid
|
icpurple
Stranger

Registered: 01/14/21
Posts: 112
Last seen: 9 months, 30 days
|
Re: BOD's Easy AF how to use your pressure cooker for mycology TEK [Re: Caleb83838]
#27245711 - 03/09/21 09:12 PM (2 years, 10 months ago) |
|
|
If it is simply the noise you are mostly concerned, as I've already explained why you want to have the jiggler jiggling to get rid of the air that continues to leave the containers as the pressure/temperature rises inside the PC after the weight is put on you can place a facecloth with a hole cut in the center of it and a large cup over the weight. I'm using a double layer of some light weight canvas as an insulator, see pics...
I check the effectiveness of this with my sound level meter and it's at least a 20 dB drop in sound pressure with both weights rockin' out. And if you take into account that every 3 dB difference equals a halving or doubling in sound pressure, it is quite significant.
|
mvcl
burrow and bury
Registered: 03/14/21
Posts: 1
Loc: N. Calif.
Last seen: 2 years, 8 months
|
Re: Bod's Easy AF how to use your pressure cooker for mycology TEK [Re: JewishLawyer]
#27253236 - 03/15/21 12:16 AM (2 years, 10 months ago) |
|
|
For rubber parts to slide and seal more easily, use KY Jelly. It's made not to degrade rubber or latex. Works well for rubber hoses on hot car engines too.
|
gone-pear-shaped
Stranger than fiction

Registered: 10/30/17
Posts: 822
Last seen: 5 months, 15 days
|
Re: BOD's Easy AF how to use your pressure cooker for mycology TEK [Re: bodhisatta]
#27337537 - 06/06/21 01:02 PM (2 years, 7 months ago) |
|
|
Quote:
bodhisatta said: As long as half of your jar is above water there's sufficient contact surface for STEAM. STEAM is what does the sterilization you want your jars to have at least 50% of their surface above the water so that steam can transfer energy to the jars.
I think you may have borrowed this idea from PF Tek, which used steam sterilization. But pressure cookers reach an equilibrium where the steam and water are the same temperature. In a pressure cooker, water will transfer energy faster due to its greater thermal conductivity.
However there is another reason not to let the water get too high on the jars--if the water covers the foil all the way around, I believe vacuum will suck water into the jar as the PC cools.
|
Big_Dub
I'm just some guy



Registered: 01/12/11
Posts: 2,639
Loc: Los Angeles
Last seen: 1 hour, 31 minutes
|
Re: BOD's Easy AF how to use your pressure cooker for mycology TEK [Re: gone-pear-shaped]
#27337630 - 06/06/21 02:15 PM (2 years, 7 months ago) |
|
|
Yeah but the steam is still there and still contributing to the sterilizing
The steam is what gets in the jars not the water
-------------------- split_by_nine said: click me you fuck do the right thing
|
bodhisatta 
Smurf real estate agent


Registered: 04/30/13
Posts: 61,889
Loc: Milky way
|
Re: BOD's Easy AF how to use your pressure cooker for mycology TEK [Re: gone-pear-shaped]
#27337694 - 06/06/21 03:19 PM (2 years, 7 months ago) |
|
|
Quote:
gone-pear-shaped said: But pressure cookers reach an equilibrium where the steam and water are the same temperature. In a pressure cooker, water will transfer energy faster due to its greater thermal conductivity.
Wrong. Same temperature yes. The steam has significantly more thermal energy
|
gone-pear-shaped
Stranger than fiction

Registered: 10/30/17
Posts: 822
Last seen: 5 months, 15 days
|
Re: BOD's Easy AF how to use your pressure cooker for mycology TEK [Re: Big_Dub]
#27337704 - 06/06/21 03:23 PM (2 years, 7 months ago) |
|
|
Quote:
Big_Dub said: The steam is what gets in the jars not the water
You may have some confusion about how stuff gets hot in the PC. It's not due to steam ingress, as evidenced by the fact that sealed bags and closed media bottles also get sterilized, and they don't take longer than bottles with vents.
There's also the fact that when you mix a liter of hot steam with a liter of cold grain, you end up with a liter of cold grain and around 2 mL of cool water. Steam has very little mass and doesn't carry much heat.
|
gone-pear-shaped
Stranger than fiction

Registered: 10/30/17
Posts: 822
Last seen: 5 months, 15 days
|
Re: BOD's Easy AF how to use your pressure cooker for mycology TEK [Re: bodhisatta]
#27337775 - 06/06/21 04:21 PM (2 years, 7 months ago) |
|
|
Quote:
bodhisatta said:
Quote:
gone-pear-shaped said: But pressure cookers reach an equilibrium where the steam and water are the same temperature. In a pressure cooker, water will transfer energy faster due to its greater thermal conductivity.
Wrong. Same temperature yes. The steam has significantly more thermal energy
Are you referring to the fact that steam will constantly condense on the cool walls of a jar and will transfer its latent heat of evaporation? Yes, that would have a strong effect. I should retract my statement that the water heats better than the steam, because it's not as simple as I had been thinking... it's like a heat pipe, where heat is moved directly from the heating element to the jar.
So all I can stand by from my original statement is that water is an excellent conductor, and the jars will get hot plenty fast in water. I don't know whether the water or steam heats faster (it's not simple math), and I don't have the equipment to test it.
(Physics nitpick: speaking of thermal energy in the literal sense: no, the steam still does not have much thermal energy due to the fact that its density is so low and there is little steam mass, even in the whole PC.)
|
bodhisatta 
Smurf real estate agent


Registered: 04/30/13
Posts: 61,889
Loc: Milky way
|
Re: BOD's Easy AF how to use your pressure cooker for mycology TEK [Re: bodhisatta]
#27337799 - 06/06/21 04:37 PM (2 years, 7 months ago) |
|
|
Wrong again please see my pressure cooker tek for educational links
https://www.engineeringtoolbox.com/saturated-steam-properties-d_273.html
Here's a quick reference easily showing how significantly more energy steam has
|
gone-pear-shaped
Stranger than fiction

Registered: 10/30/17
Posts: 822
Last seen: 5 months, 15 days
|
Re: BOD's Easy AF how to use your pressure cooker for mycology TEK [Re: bodhisatta]
#27338223 - 06/06/21 10:57 PM (2 years, 7 months ago) |
|
|
Quote:
bodhisatta said: Wrong again please see my pressure cooker tek for educational links
https://www.engineeringtoolbox.com/saturated-steam-properties-d_273.html
Here's a quick reference easily showing how significantly more energy steam has
TL;DR: you're ignoring density. Density matters.
Perfect, let's use that chart (assuming 14 PSI). Per pound, water has 216 Btu. Or per cm3, that's 502 joules. ($ units '216 (btu/lb) / (1 (cm3/g))' 'joules/cm3')
Per pound, moist steam (this is what a pressure cooker has) has 947 Btu per pound but a pound takes up 14.3 ft3 of space. Since the density is so low, per cm3 that only 2.47 joules. ($ units '947 (btu/lb) / (14.3 (ft3/lb))' 'joules/cm3')
This is a tiny fraction, as I've been saying. However, there will still be efficient energy transfer due to condensation which imparts a ton of energy. (If you prefer not to normalize, steam will have 70 thousand joules of energy in a ft3 of headspace, while the hot water will have 1.5 million joules of energy in the 3 liters of water in the bottom.)
I'm really grateful for your contributions to the community. I don't intend to bother you or pick a fight, I just want to encourage correct math and physics since that's my area of knowledge.
Edited by gone-pear-shaped (06/06/21 11:00 PM)
|
bodhisatta 
Smurf real estate agent


Registered: 04/30/13
Posts: 61,889
Loc: Milky way
|
Re: BOD's Easy AF how to use your pressure cooker for mycology TEK [Re: bodhisatta]
#27338440 - 06/07/21 04:45 AM (2 years, 7 months ago) |
|
|
Physics is my strong point yet two posts ago you said.
Quote:
gone-pear-shaped said: But pressure cookers reach an equilibrium where the steam and water are the same temperature. In a pressure cooker, water will transfer energy faster due to its greater thermal conductivity.

https://www.engineeringtoolbox.com/saturated-steam-properties-d_457.html
|
bodhisatta 
Smurf real estate agent


Registered: 04/30/13
Posts: 61,889
Loc: Milky way
|
Re: BOD's Easy AF how to use your pressure cooker for mycology TEK [Re: bodhisatta]
#27338447 - 06/07/21 04:49 AM (2 years, 7 months ago) |
|
|
|
gone-pear-shaped
Stranger than fiction

Registered: 10/30/17
Posts: 822
Last seen: 5 months, 15 days
|
Re: BOD's Easy AF how to use your pressure cooker for mycology TEK [Re: bodhisatta]
#27338529 - 06/07/21 06:48 AM (2 years, 7 months ago) |
|
|
I liked that last link. (But of course, it expands on what I wrote a few posts ago, where I compared heat by steam condensation to how a heat pipe works.)
There is plenty more to write but I'm going to beg off. I hope you don't mind. I leave you with a parting thought experiment: if you turned off the PC after a short time at pressure like five minutes, would the submerged jar or the elevated jar get hotter? What if you turned it off as soon as it reached pressure? When you boil stew, does the meat above the water get cooked? Why not? I think the answers to these questions reveal why it's not a bad thing to have jars submerged during the PC cycle, despite the high energy imparted by steam condensation.
|
bodhisatta 
Smurf real estate agent


Registered: 04/30/13
Posts: 61,889
Loc: Milky way
|
Re: BOD's Easy AF how to use your pressure cooker for mycology TEK [Re: gone-pear-shaped]
#27338572 - 06/07/21 07:54 AM (2 years, 7 months ago) |
|
|
There's a reason the manufacturers of autoclaves mention everything needs to be exposed to steam and out of the water. It's literally part of basic sterilization failure troubleshooting
|
bodhisatta 
Smurf real estate agent


Registered: 04/30/13
Posts: 61,889
Loc: Milky way
|
Re: BOD's Easy AF how to use your pressure cooker for mycology TEK [Re: bodhisatta]
#27338584 - 06/07/21 08:07 AM (2 years, 7 months ago) |
|
|
. Direct Steam Contact Direct steam contact with the surface of the object to be sterilized is required for the steam to transfer its stored energy to the object. Without direct steam contact to all surfaces, the item will not be sterilized. The amount of energy stored in steam is much higher than dry air or water at the same temperature. From the saturated steam table mentioned above, one can see that it takes 419 kJ/kg (180 Btu/lb) to heat water from 0Β°C to 100Β°C (32Β°F to 212Β°F). This is the enthalpy of water (hl). It takes an additional 2,257 kJ/kg (970 Btu/lb) to create steam at atmospheric pressure (100Β°C or 212Β°F). This additional energy stored in the steam is the enthalpy of vaporization (he), and is the key to steam sterilization. In order for the steam to transfer its stored energy, it must condense on the surface of the object being sterilized.
https://ispe.org/pharmaceutical-engineering/november-december-2013/steam-sterilization-principles-common-mistakes#
Latent heat is really misunderstood. For example superheated steam at 300F is not as energetic as 250F saturated steam. Even under pressure 300F water wouldn't transfer heat as well as saturated steam at 250F
|
MerryTerry
Rope Runner



Registered: 11/18/20
Posts: 50
Loc: La Chorrera
Last seen: 1 year, 1 month
|
Re: BOD's Easy AF how to use your pressure cooker for mycology TEK [Re: bodhisatta] 1
#27351323 - 06/16/21 09:12 PM (2 years, 7 months ago) |
|
|
I see you are still active on this thread Bod- Thanks for your ongoing attention to detail and great teks. I always consult your oats pipeline and it remains essential. Something unusual happened today while PCing, which I thought I'd point out for fellow noobians:
When loading and packing, be careful the venting pop-up valve doesn't get jammed up against the jars and stuck closed. It can be impossible to tell from glance alone, but when the old presto was venting today it was dripping excessive water through the valve yet the steam was weak and choppy. I waited for several minutes no pop. Then some strange sounds. Knew something wasn't right so I turned it off and waited several more mins to cool (wear mits to release or you'll scorch your hands), and turns out valve must have been perfectly jammed against the jars with no wiggle room. Finagled the scorching bastards and started the process from scratch and hey presto, Bod's works a charm, as per always. Anyways hopefully this is helpful to someone learning on the job like myself. Cheers!
-------------------- "Take it easy dude... But, take it!" -TM

|
|