|
CreonAntigone
Stranger

Registered: 05/30/21
Posts: 3,374
|
Is there a way to stop no-pour agar from boiling over?
#27788887 - 05/22/22 11:46 PM (2 years, 7 months ago) |
|
|
It seems like if I get it hot enough, some of it boils over and gets through the holes in the lid.
Is there some way to prevent this?
|
BlueAndOrange
Psychedelic success story…


Registered: 01/11/22
Posts: 1,079
Last seen: 9 days, 8 hours
|
Re: Is there a way to stop no-pour agar from boiling over? [Re: CreonAntigone]
#27788891 - 05/22/22 11:55 PM (2 years, 7 months ago) |
|
|
I’m not sure how you’re doing it but when I was doing pasty plates, I never boiled over. Are you letting your PC cool down slowly?
Edited by BlueAndOrange (05/22/22 11:56 PM)
|
Gorguss
Chaotic sums


Registered: 02/03/10
Posts: 710
Last seen: 1 month, 12 days
|
Re: Is there a way to stop no-pour agar from boiling over? [Re: BlueAndOrange]
#27788923 - 05/23/22 12:34 AM (2 years, 7 months ago) |
|
|
I fill a 1500mL Erlenmeyer flask with 1000mL of agar and put polyfil (stuffed in a wad) or a Styrofoam plug (bought specifically for this) in the top, with aluminum foil over that. Next elevate the flask above the water line in the pressure cooker. Then normally bring to pressure and 15psi @ 45min or whatever you do. Finally let the Pressure Cooker cool simply by turning off the heat and waiting until its 0psi. Then wait another 15-30min before finally opening it in front of a Flowood or near your workstation.
Letting it cooldown too fast will cause it. I.E., removing the weight to release pressure.
Also mixing with a hand blender really did wonders for how clear and homogenous it turned out after PC. Wait to pour at 140F-135F, helps with condensation.
-------------------- ------------
Looking for Trichocereus Cacti
------------
|
chris77
Archaic Revivalist



Registered: 01/17/22
Posts: 2,105
Last seen: 21 seconds
|
Re: Is there a way to stop no-pour agar from boiling over? [Re: CreonAntigone]
#27788924 - 05/23/22 12:35 AM (2 years, 7 months ago) |
|
|
post a pic of your container? i do no-pour in pp5 containers with screw lids. never had it boil over.
-------------------- the observer is the observed
j. krishnamurti
|
chris77
Archaic Revivalist



Registered: 01/17/22
Posts: 2,105
Last seen: 21 seconds
|
Re: Is there a way to stop no-pour agar from boiling over? [Re: Gorguss]
#27788925 - 05/23/22 12:37 AM (2 years, 7 months ago) |
|
|
Quote:
Gorguss said: I fill a 1500mL Erlenmeyer flask with 1000mL of agar and put polyfil (stuffed in a wad) or a Styrofoam plug (bought specifically for this) in the top, with aluminum foil over that. Next elevate the flask above the water line in the pressure cooker. Then normally bring to pressure and 15psi @ 45min or whatever you do. Finally let the Pressure Cooker cool simply by turning off the heat and waiting until its 0psi. Then wait another 15-30min before finally opening it in front of a Flowood or near your workstation.
Letting it cooldown too fast will cause it. I.E., removing the weight to release pressure.
Also mixing with a hand blender really did wonders for how clear and homogenous it turned out after PC. Wait to pour at 140F-135F, helps with condensation.
he wanted to know about no-pour
-------------------- the observer is the observed
j. krishnamurti
|
DERRAYLD
Constructus


Registered: 05/13/02
Posts: 12,109
Loc: South Africa
Last seen: 7 hours, 27 minutes
|
Re: Is there a way to stop no-pour agar from boiling over? [Re: chris77]
#27788947 - 05/23/22 01:25 AM (2 years, 7 months ago) |
|
|
Allow your pc to cool to 0 psi before opening it.
|
chris77
Archaic Revivalist



Registered: 01/17/22
Posts: 2,105
Last seen: 21 seconds
|
Re: Is there a way to stop no-pour agar from boiling over? [Re: DERRAYLD]
#27788963 - 05/23/22 01:50 AM (2 years, 7 months ago) |
|
|
Quote:
DERRAYLD said: Allow your pc to cool to 0 psi before opening it.
I don't really see the benefit. releasing the pressure and opening right away works just fine for me.
-------------------- the observer is the observed
j. krishnamurti
|
DERRAYLD
Constructus


Registered: 05/13/02
Posts: 12,109
Loc: South Africa
Last seen: 7 hours, 27 minutes
|
Re: Is there a way to stop no-pour agar from boiling over? [Re: chris77]
#27788976 - 05/23/22 02:19 AM (2 years, 7 months ago) |
|
|
That's wrong on so many levels.
You are supposed to allow your pc to cool and drop to 0 psi before opening or you are forcing the pc to drop pressure too fast.
|
DERRAYLD
Constructus


Registered: 05/13/02
Posts: 12,109
Loc: South Africa
Last seen: 7 hours, 27 minutes
|
Re: Is there a way to stop no-pour agar from boiling over? [Re: DERRAYLD]
#27788979 - 05/23/22 02:26 AM (2 years, 7 months ago) |
|
|
https://teach.genetics.utah.edu/content/microbiology/liquids/
Pt #5
Remove the pressure cooker from the heat source and let the pressure gradually decrease on its own. if you remove the weight from the steam vent, the liquids will boil over.
Science exists
|
chris77
Archaic Revivalist



Registered: 01/17/22
Posts: 2,105
Last seen: 21 seconds
|
Re: Is there a way to stop no-pour agar from boiling over? [Re: DERRAYLD]
#27788980 - 05/23/22 02:33 AM (2 years, 7 months ago) |
|
|
Quote:
DERRAYLD said: https://teach.genetics.utah.edu/content/microbiology/liquids/
Pt #5
Remove the pressure cooker from the heat source and let the pressure gradually decrease on its own. if you remove the weight from the steam vent, the liquids will boil over.
Science exists
well, to be honest i have not released the pressure right when its still boiling inside. but it occured that i havent waited more than 15 minutes, and quite some pressure left when i lifted the weight.wasnt a problem
-------------------- the observer is the observed
j. krishnamurti
|
DERRAYLD
Constructus


Registered: 05/13/02
Posts: 12,109
Loc: South Africa
Last seen: 7 hours, 27 minutes
|
Re: Is there a way to stop no-pour agar from boiling over? [Re: chris77]
#27788984 - 05/23/22 02:47 AM (2 years, 7 months ago) |
|
|
I'm glad that worked for you but it's not advisable.
The question is related to boiling over which is explained above.
|
chris77
Archaic Revivalist



Registered: 01/17/22
Posts: 2,105
Last seen: 21 seconds
|
Re: Is there a way to stop no-pour agar from boiling over? [Re: DERRAYLD]
#27788986 - 05/23/22 02:51 AM (2 years, 7 months ago) |
|
|
Quote:
DERRAYLD said: I'm glad that worked for you but it's not advisable to do that.
The question is related to boiling over which is explained above.
i agree with you!
-------------------- the observer is the observed
j. krishnamurti
|
Goatrider
Rhythm Guitarist



Registered: 04/08/20
Posts: 4,801
Loc: Germany
|
Re: Is there a way to stop no-pour agar from boiling over? [Re: chris77]
#27788988 - 05/23/22 02:59 AM (2 years, 7 months ago) |
|
|
Few reasons why i wouldn´t force unpressuring:
- Glass becomes fragile, may get undetectable cracks - Moisture content in grain jars can be ruined, moisture gets vapored out - Don´t wanna suck contams in
If not cooled down overnight, i take out grain jars when i can touch the outside of the pc with my hands without burning myself. Agar bottles ~half an hour after the safety valve pops down.
--------------------
|
|