Nan's Nook : Archives : Pressure Cooker : Pressure Cooker 101 : Steamer
  Subtopic Posts Updated Creator
PC  -    
Boiling Jars Instead of using PC  22 12/08 02:01am Rick
Links to vendors  -    
Steaming cant be all that bad, can it?  18 12/08 02:01am jared
One more question till inoculation..  12 01/02 07:39pm The Silly Scybe Scribe

By Brad (Raze) on Monday, October 01, 2001 - 07:58 pm:

Is a slow cooker, or "Crock Pot" the same as a pressure cooker? I know we have one of those.
If not oh well, guess its the old boiling pot method.

By Nanook of the North (Nanook) on Monday, October 01, 2001 - 08:24 pm:

Nope. A Pressure Cooker is a pot with a lug or clamp sealed lid designed to heat water up to temperatures of 250*F with up to 15 pounds of steam pressure.

By Brad (Raze) on Monday, October 01, 2001 - 08:45 pm:

Crap... How much do those go for?
And is the boiling water in a pot thing just as effective? Someone told me that most people get like major contam with it

By Merlin of Camelot (Merlin) on Monday, October 01, 2001 - 11:16 pm:

Brad, I don't have a lot of experience or a pressure cooker. I always boil in a pot on one of those vegetable steamers to keep the jars off the bottom. Boil 1 hour and so far never lost a jar.

By Fishy1 (Fishy1) on Monday, October 01, 2001 - 11:21 pm:

just make sure yer jars dont take on water---put foil on, dont boil too hard, and use somethin to keep the jars off the bottom of the pot.
Many fruits, fishy1

By Underground_Shaman (Shaman) on Tuesday, October 02, 2001 - 03:18 pm:

I too use a boiling pot exclusively with a little metal "shelf" (jimmied from an old metal test-tube rack) to keep jars off the bottom. I have never lost a jar to this method (several hundred and counting...), only to contaminated innoculum.


By Brad (Raze) on Wednesday, October 03, 2001 - 03:24 am:

Great, then I'm fine. I've got plenty of big pots around here for making soups and stuff.

By Snorgleborf (Snorgleborf) on Thursday, October 04, 2001 - 01:40 am:

Water boils at 212°F, not hot enough to kill all the possible nasties out there. At 15 psi of pressure the temp inside a PC reaches 250°F. Of course if your inoculum is contaminated, it really doesn't matter how well sterilized your substrate is. It's extra insurance and well worth it IMHO. Models that will hold six jars at a time start at around like $30 at Wal-mart. A larger model that will hold 24 half-pints is $72 at Wal-mart.

By oscill8 (Oscill8) on Thursday, October 04, 2001 - 02:00 am:

pressure cookers also mean you can try different substrates, do agar work, sterilize your syringes/works, etc. check ebay too.

By Brad (Raze) on Thursday, October 04, 2001 - 02:15 am:

Yes but a large investment for an initial mushroom kit.
I think I can only do about 3-4 batches before I leave for university, then I'll lay low for a while to make sure there arent room checks int he doorm and such.

By Lichen (Lichen) on Thursday, October 04, 2001 - 05:10 am:

Please excuse me, but I beg to chip in. I don't own a pressure cooker, and a steam bath works well. It works fine for canning fruit, and I've never had problems there; neither is there a problem with substrate jars. An hour in the steam kills everything. Name me a creature that can stand an hour at 200F.

By monkeyod (Monkeyod) on Thursday, October 04, 2001 - 06:07 am:

I'm sure any of the 90 some odd recorded species that live off the Hydrothermal vents on the ocean gets up to 400c(not f) there.

But I don't think you'll find many of these in your kitchen.

By oscill8 (Oscill8) on Thursday, October 04, 2001 - 01:29 pm:

botulism for one can survive up to 250F. an hour in 212 degree will not kill everything. trying something ELSE than pf tek (or flour teks) ina waterbath canner will almost guarantee you improper steilization and contams.

there are 2 kinds of canners, water bath and steam pressure. high acid foods like fruits can be used in a waterbath canner as nasties (like botulism) cannot survive in a high acid enviro. low acid foods must be canned in a steam pressure canner, since botulism can reside and live in the enviro up to 250 degrees F. this is why meats can never be canned using a water bath canner, while fruits can be. substrates like birdseed, and whole grains are not high acid "foods"- and botulism (as well as other banes of cultivation) can survive within the waterbath. hard shelled grains hide many nasty things within them- and pressure canning is the only way to penetrate them and sterilize them. much of this information can be found readily on the web doing a search for high/low acid foods and home canning (not part. about the hobby, but about canning. TMC outlines proper sterilization temps for substrates as well).

steam pressure canners can achieve a psi of 15- (or more, depending if youre commercial or not)- water heated under 15 psi is 250 degrees. boiling water that is not under pressure will not achieve a temp above 212 (except for altitude differences- but then its minimal)... and cant be used to adequately sterilize bulk substrates, agar, meat, or anything else that is not high acid.

im not knocking waterbath for sterilization of pf substrates; its how HQ started doing pf jars. but there is a difference between water bath and steam pressure canners.

By Lichen (Lichen) on Thursday, October 04, 2001 - 01:44 pm:

Well, I am aware that I cannot can vegetables and meats without a pressure cooker...and as to the hard shelled grain harboring nasties, I'm sure you're right. I stand corrected.

I also stand corrected on the creatures thriving on the geothermal vents in the ocean floor, although I didn't realize the temp they thrive in is quite that hot; my ground rice jars sterilize handily in steam bath.

I probably need to become less obtuse and get myself a pressure cooker and stop putting my foot in my mouth--it's not very tasty :0)

By Underground_Shaman (Shaman) on Thursday, October 04, 2001 - 03:33 pm:



Really though, know what your talking about please.

Yes, steam doesn't work as well for other substrates (grains or agar), but even PF himself says that this is an ADVANTAGE of the PF tek. Using ground BRF only requires steam sterilization. Pure and simple.


By An guy (Boomer) on Monday, October 29, 2001 - 05:11 pm:

I dont' have a pc, I used one of those 3-piece Martha Stewart steamer deals you can get at Kmart-deep pot, colander type insert, and a lid.

Put water in till it was a little over the bottom of the insert, which put it a little bit up the sides of the jars when I put them in. Boiled the whole thing.

It worked fine so far- I have contams but they're only with my portobellos, so I have to think that it's from my scrapings, not my sterilizing.

I did stack up some rocks to balance a gallon can of roofing tar on the lid of the steamer, just to hopefully get a couple pounds of pressure at least.

By jared (Jared112) on Tuesday, November 13, 2001 - 06:04 pm:

I just took my first 4 jars out of the pot that I boiled them in for 1.5 hours. I noticed that the foil looks black towards the bottom. Is this normal. I had the jars about 1/3 submerged in water. The substrate also looks the same as it did when I put them into the pot. They should be sterile all the way through right?
sterile jars

....... Foil Covers!

By quote: (Quote) on Tuesday, November 13, 2001 - 06:21 pm:

look ok, you used cheap foil and Tap Water so the blackness happens, no big deal.

Shroom Glossary

By Scott Anthony (Greenthumb422) on Sunday, December 09, 2001 - 02:28 am:

Im new to this. I haev a steamer and I got 3 jars ready to steam. How long do I put them in for? And what temperature?

By jim brown (Shrhobbyist) on Sunday, December 09, 2001 - 02:48 am:

If you mean a regular non-pressure pot the temperature will be 212degrees, which it is as high as the water can be without the pressure element. Set it on simmer, that is as low as it can go while still boiling/bubbling. Try not to let it bubble too much because the water can splash into the holes in the lid. And do this for 60 minutes.