Pressure Cooker for Sterilising

[sladeywadey]

Hi - I have an instant pot duo pressure cooker which operates around 11 psi. Is this OK for preparing starter worts, sterilsing yeast vials/jars/water etc?

[barneey]

Your looking for at least 121c for 15mins, which is circ 15psi

[Jocky]

11psi should get to about 116c.

It's not going to achieve medical grade sterilisation, but I think that for organisms encountered in brewing environments 30 mins should achieve effective sanitation for most purposes.

Certainly I'd like to hear if someone disagrees.

[sladeywadey]

11psi should get to about 116c.

It's not going to achieve medical grade sterilisation, but I think that for organisms encountered in brewing environments 30 mins should achieve effective sanitation for most purposes.

Certainly I'd like to hear if someone disagrees.

Thanks for that. I did read that pressure cookers in the USA are capable of 15psi but it seems the ones available in the UK aren't. So in general, I need enough water in at the beginning to last 35 mins (to be on the safe side!).

I also read that lids must be on tight when 'canning' but I think I read some posts on here that seemed to suggest that the lids need to be loose?

[Jocky]

As long as the valve on the lid is in 'sealed' mode then it shouldn't be losing any water while running.

I should say that if you want to really make yeast ranching/isolating etc a central part of your brewing regimen, investing in a proper pressure cooker/autoclave will be worth it.

[sladeywadey]

thanks - I can't find anything suitable for 15psi though unless i pay a fortune to import from the USA

[barneey]

To clave, make sure you get rid of the air in the chamber, this will result in loosing liquid in the procedure. 121c in a proper clave is easily surpassed, there are tests that can be carried out to identify sterilisation.

I would suggest with the equipment you have, make several virgin slants, yeast one, open air then close one & leave the others for a period of time, see what grows.

[Aleman]

Prestige hi dome pressure cooker does 15 psi and is available in the UK

[vacant]

Prestige hi dome pressure cooker does 15 psi and is available in the UK

I have one. The specs you find (copied from the prestige.co.uk) state "This 6L cooker has a three piece weight for 5, 10 and 15lb cooking.". That can only mean "lb psi", they probably omit the psi bit so as not to scare or confuse consumers.

Anyway, when I was looking, the modern ones with a valve in the handle tended to be 11 while the traditional ones with a hole in the centre have weights for 15.

[sladeywadey]

Thanks guys, Vacant do you use your prestige with jars etc? Just wondered how roomy they are in use.

[vacant]

Thanks guys, Vacant do you use your prestige with jars etc? Just wondered how roomy they are in use.

Mostly I boil one and two litre conical flasks on the gas sitting on a wire gauze but a one litre conical flask will just fit in the pressure cooker supported by the inverted wire spacer to allow water to circulate under the flask better.

[sladeywadey]

Thank you - I mainly need it for my 500ml kilner jars for storage along with autoclavable vials. Think I'll nip to Argos for one.

[barneey]

In my experience, if you use the kilner jars (flip top ones) the clamping wire will go rusty reasonable quickly. Normal Jam Jar type Kilners are fine though.

[john luc]

I bought this one that this lad uses. Its from Amazon and he links to it. Its really good and I get it over 15 psi when on the cooker.
https://www.youtube.com/watch?v=XN1u-KNmejA&t=122s

[Aleman]

Yeah I was looking at the Presto Canner . . . and a Mirra (??) one, but then I went the Whole hog and got a All American 930

Of course that is in addition to the Hi Dome . . . and the Tefal . . . and the . . . Hmmm I think I may have a problem