pressure cooker?

[horsethefan]

Is it possible to sterilize your jars without a pressure cooker? if not where can i get a good pressure cooker in the uk?

 

[JustinNed]

I don't think so, I've heard of people microwaving substrate but I don't know if that works. You can order one off the internet if all else fails.

 

[Meduzz]

Lowering the sterilisation temperature about 15°C usually results in a decimal reduction time multiplied by 10.

The standard for sterilisation in an autoclave at 121°C is generally 10-15 minutes, so at 100°C an hour and half or two hours should be sufficient. I have successfully sterilised PF cakes in normal cooking pots for an hour if I remember right.

!!! As opposed to a high pressure cooker water CAN escape so check regularly if it hasn't boiled dry yet.

edit: decimal reduction time is the time needed for a tenfold reduction of the bacterial population.

 

[GOD]

Its better to buy a new one than a second hand one . They are not expensive and well worth the money as they can be used to cook food in faster and with less loss of vitamins than a "normal" sauce pan .

 

[JustinNed]

Quick question for ya GOD, sense you brought up the 2nd hand pressure cooker. I loaned mine out to a friend and his friend ended up taking it and by the time I got it back there was some odd shit left in it, almost like an epoxy. It's some brown shit and doesn't wanna come of plus it smells like shit.

This won't effect sterilizing jars will it? Not too long ago I used it in that condition to sterilize some jars for the "popcorn tek" but ended up with 0/4 colonizing which I'm pretty sure is because I had to actually take the jar lids off for inoculation (syringe needle jammed)

 

[GOD]

Get the shit out . Or sell it the person that shit in it and buy a new one .

Use physical force ( In my opinion on it and / or on him........ ) to get it off = wire wool and pumice powder . And / or soak it in solvents . If you cant get it out throw it away .

It would be good if you gave him an "inteview" and he said what the shit is .

 

[JustinNed]

I don't even know the guy, it was my friends roommate and when they got kicked out of the house all my mushroom kit got scattered across 3 different people I went through hell getting it back. I'll try some steel wool/sand paper since I have No idea what it is I'll refrain from using solvents.
Worse comes to worse I suppose I'll toss another $20 on another cooker, thanks mate.

 

[GOD]

I would bet its either something cooked on = its just a matter of wire wool and sand if you have no pumice plus elbow grease . Or the bastard has been mixing something to fill holes in his car or fix his surf board = throw it away and buy a new one .

 

[JJJ]

I sterilize my substrate without a PC . It is a little more work though, using a PC is much more convenient and maybe also more contaminant-free. I use the so called 'fractional sterilization' method, which means that you cook your substrate at 100C in a normal pan for +- 45min, three times in a row with 24h in between. It works for me on most (full grain) jars .

But once I have a kitchen of my own, I will get myself a pressure cooker as it's much more convenient to use.

 

[Meduzz]

Why 24 hours in between? It's better to cook a bit longer in one time and inoculate as soon as the temperature is OK.

 

[JJJ]

Why 24 hours in between? It's better to cook a bit longer in one time and inoculate as soon as the temperature is OK.

As far as I understand it, the problem is the endospores of some bacteria. At 100C, all bacteria and fungi+fungi spores are dead, but some bacteria leave endospores, which can still germinate. In 24 hours at room temperature, these have germinated into bacteria, so you cook again to kill those bacteria (before they could form endospores again). The third time is to be completely certain that you have killed all endospores. In a pressure cooker, you don't have a problem with endospores because at those temperatures (+-140C I think) they are killed instantaneously.

 

[Meduzz]

Growth occurs from endospores after about 12 hours. The bacterial population doubles every 30 minutes and makes new endospores -> more endospores

I must say it did look like a good idea. But I think you should wait less longer.

 

[GOD]

I think you should get a preasure cooker .

 

[JJJ]

Growth occurs from endospores after about 12 hours. The bacterial population doubles every 30 minutes and makes new endospores -> more endospores

I must say it did look like a good idea. But I think you should wait less longer.

Hmm, maybe that would be more optimal. It works though, where cooking just one time doesn't. Fractional sterilisation is also called Tyndallisation, and traditionally a period of 24h is used between the steps. http://en.wikipedia.org/wiki/Tyndallization .

But well, let's not focus too much on this method indeed. I can only say that it works for me, but that using a PC probably is the best option. If you are doing your first grow, you don't want the extra uncertainty of not using a PC; it would make it even extra unsure to find out where the problem is, if it goes wrong.

 

[horsethefan]

I think you should get a preasure cooker .

Any suggestions on the dimension of the pressure cooker or brand?

 

[GOD]

The brand doesnt matter and the size depends on the size of the containers that you want to put in to sterilise .

 

[poisoninthestain]

possible? yes. practical? not exactly.

 

[tryptonaut]

I have a pressure cooker from the early 80ies (used to be my moms) and its still doing its job.

You can get these things everywhere where you can buy kitchen equipment. They're pretty standard tools in kitchens all around the world.

I use it mostly to cook potatoes, because it takes half the time and 1/4 of the gas. You'd have to cook them 45 minutes on full heat in a normal pot, in the pressure cooker they're done in 20 minutes, 10-15 of which are on lowest heat only. I guess I'd never eat fresh potatoes if I didn't own that pressure cooker.

I just used it the first time to sterilise mushroom jars (I was always having ready-made grow-boxes before). I found out the cooker was so small I can hardly fit in two jars... well, I can live with that I guess.