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blackout


Registered: 07/16/00
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Cook dry grains at high pressure to hydrate and sterilize 2
#22076763 - 08/11/15 02:47 PM (8 years, 5 months ago) |
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I have been hydrating grains by boiling in excess water at about 5psi for about 30-35mins and letting it rest on the warm hob to cool. These are not soaked or rinsed in any way.
I just did 600g of barley (similar to rye) in excess water and this time I let it go up to about 23psi and letting it cool. It remain past 15psi for probably 15mins at least, maybe 20mins max. When it reached 15psi I took it off the warm hob to cool down a bit faster. I did not want to vent it as this can cause grains to explode. My overall cook time from the time the grains went into almost boiling water was maybe 40-45mins. As most will know higher pressure results in a higher temp and much shorter times are required to achieve the same level of reduction in contams. The reason we usually do 60-120mins in a PC is that the core of the jar takes a long time to reach temp.
The graph below shows the large can took about twice as long to reach the same core temp as the small one.

I was surprised to find I did not have many more exploded grain than normal, also they were not overly hydrated. They weighed about 1250g after. So this is 108ml per 100g dry added, which is a common enough forumla for those familiar with weight based recipes. These grains were intended for sclerotia so I was not overly concerned about overhydration or exploded grains.
I may have posted before of methods of getting to pressure quicker, so as to minimize actual cooking time to prevent overhydration. One idea is to microwave or dry roast the grains so they are 100C or over (yes they can get over 100C and still have moisture in them). Now you would have your PC full of water on a rolling boil, lid on and preheated and venting, hob on full power. Now you dump your hot grains into the boiling water and stick the lid on. This minimizes the heat up time so you might be at 15psi pretty quick. I do not think there is any need to even vent the PC of steam as the grains are all submerged in water, you are not cooking jars in the saturated steam.
I have posted before about maximizing the space of a small PC in different ways. One was to fill a large tub which snugly fits into the PC and fill it with grain. Then fill the still hot grains into many smaller jars and heat these again, by steaming or microwaving. This means any airbourne contaminants should be killed easily enough and I can fit about twice the amount of grains into the PC.
When using my large container method I had to PC for longer times to heat to the very core. But if heating directly in water there is no issue, all the grains are surrounded by the boiling water which is freely circulating around the pot. I can also get even more grains into the PC than before. My one concern is that the cores of the grain may not be hydrated quick enough and there could be air pockets insulating them, but I feel the surrounding water is close enough and has enough circulating hot water in direct contact to do the trick.
If you use large containers this may be a quicker method to sterilize. e.g. I have 4.5L containers and if they did fit in my PC I would want to give them a good 3 or 4 hours to be sure. With this method it could possibly be in the PC for 30-35mins, and microwaved for 20-30mins or so. Microwaving ensures it is up to a boiling temp pretty quick. If your PC does not go past 15psi it might still work. Quoted textbook times needed are far shorter than what we use, as they are talking of thermal death times at that time, and we do much longer to heat the core.
TL;DR- I propose pressure cooking grains in excess water past 15psi to sterilize and hydrate, then load them in open air into containers and heat again without pressure to kill off any new contams that landed in them.
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champinhom
Lord Justhappensness


Registered: 03/06/09
Posts: 987
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Re: Cook dry grains at high pressure to hydrate and sterilize [Re: blackout]
#22077021 - 08/11/15 03:43 PM (8 years, 5 months ago) |
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So, you boil the grain loose in the pc to sterilize/hydrate--then what? You have to transfer them to some kind of container where they can be colonized, no? That process of transfer would be fertile ground for contamination, seems to me.
-------------------- My father used to say: I don't care what else you do in life, just don't be an asshole. People, forgive me when I forget what my daddy said. Cut back the proliferating list of people whose opinions can hurt you. Unless they have done or want to do you some good, their views are just not worth tracking. Saul Bellow “People are just cannibals unless they leave each other alone.” Doris Lessing Those whom the gods would save, they dower with compassion. Mr. P. Silocybin
Edited by champinhom (08/11/15 03:44 PM)
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bodhisatta 
Smurf real estate agent


Registered: 04/30/13
Posts: 61,889
Loc: Milky way
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Re: Cook dry grains at high pressure to hydrate and sterilize [Re: champinhom]
#22077096 - 08/11/15 04:04 PM (8 years, 5 months ago) |
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is it less work to hydrate with pressure to sterilize then load then heat without pressure to kill new microbes than it is to heat without pressure to hydrate grains and then with pressure to sterilize them? for instance you can take whole oats like for horse feed boil them 30m pour them into a strainer and then before they would pass the TP test load them into jars while they're slightly wet to wet on the outside. PC them for 90m. it seems to me that that would be less work overall to me. Is it less work in your opinion to PC hydrate grains then re heat them?
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Pastywhyte
Say hello to my little friend



Registered: 09/15/12
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Loc: Canada
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Re: Cook dry grains at high pressure to hydrate and sterilize [Re: champinhom]
#22077108 - 08/11/15 04:07 PM (8 years, 5 months ago) |
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I do this in my small PC when I am prepping bulk substrate bottles. In fact I don't even microwave, simply combine water and grain together in the PC, bring up to pressure, and they are done in 20 min, perfectly hydrated and zero exploded.
Matter of fact I did this this morning when I decided on the spur of the moment I was gonna make up some bottle subs. Prepped the bulk substrate while the grains hydrated and then dumped em right into the mix.
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newrook
Sucks at bulk



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Re: Cook dry grains at high pressure to hydrate and sterilize [Re: champinhom]
#22077128 - 08/11/15 04:11 PM (8 years, 5 months ago) |
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pc --> dry --> load --> pc ?
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  THROW AWAY YOUR SGFC
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eatyualive
Eat's You Alive :)



Registered: 08/17/01
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Loc: In Your Head
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Re: Cook dry grains at high pressure to hydrate and sterilize [Re: newrook]
#22077154 - 08/11/15 04:19 PM (8 years, 5 months ago) |
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blackout


Registered: 07/16/00
Posts: 5,266
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Re: Cook dry grains at high pressure to hydrate and sterilize [Re: bodhisatta]
#22077170 - 08/11/15 04:23 PM (8 years, 5 months ago) |
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Quote:
champinhom said:That process of transfer would be fertile ground for contamination, seems to me.
already answered
Quote:
blackout said:load them in open air into containers and heat again without pressure to kill off any new contams that landed in them.
Lots of people just boil water for 10mins or so which is believed to be enough to kill off any airbourne contams that fell in it.
Quote:
bodhisatta said: Is it less work in your opinion to PC hydrate grains then re heat them?
It depends on your individual setup. This is more suited to people who have a small PC and want to make more efficient use of it. Canning seems to be popular in the US, in other countries it is very difficult to get a large PC, or you have to pay a hell of a lot for it.
I cannot PC the containers I often colonise in, they are far too big to fit in the PC but fit in my microwave. People can get bog standard water boilers like these and load them with jars and steam. These should be easy to find in most countries.

Or you can easily make a large steamer with a large container and element.
For me its about the same amount of physical labour happening but faster turn around, so less babysitting. I would be boiling in a pot to hydrate either way, by doing it under pressure it hydrates faster and is potentially sterilizing in the process. If I did just boil I would afterwards load into jars and would PC them. I can only fit 3 jars in my PC and would do them for 2 hours.
So I can now do enough grains for maybe 9 jars and either load into a larger pot to steam, or do 3 runs of 3 jars, but if hot they do not need to be PC'd for 2 hours. If the grains have cooled I can heat them in the microwave before PC'ing or steaming.
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blackout


Registered: 07/16/00
Posts: 5,266
Last seen: 2 months, 24 days
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Re: Cook dry grains at high pressure to hydrate and sterilize [Re: blackout]
#22087333 - 08/13/15 01:52 PM (8 years, 5 months ago) |
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I shook my barley grain jars and there were more exploded ones than usual so it proved hard to shake. However the jars were also overly full and had no gypsum in them.
Still I think some other grains might be better suited, popcorn or maize are harder to hydrate so might fare better. RGS also does not really explode but is very expensive for many, and not dense so in a way not suited to what I am attempting to do.
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thoraxx
Wizard


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Re: Cook dry grains at high pressure to hydrate and sterilize [Re: blackout]
#22087585 - 08/13/15 02:44 PM (8 years, 5 months ago) |
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Are you using metal jars? That alone must make take alot off PC time, interesting idea i havent seen before
edit; wtf did i do there, i should stop posting for today
Edited by thoraxx (08/13/15 02:57 PM)
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bodhisatta 
Smurf real estate agent


Registered: 04/30/13
Posts: 61,889
Loc: Milky way
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Re: Cook dry grains at high pressure to hydrate and sterilize [Re: thoraxx]
#22087627 - 08/13/15 02:53 PM (8 years, 5 months ago) |
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metal jars would PC the quickest, then glass, than plastic. metal jars are also pretty thin. food for thought though if you have a pp5 container that's half as thick as a similar glass container the glass will still sterilize quicker that's how much better it is at heat transmittance.
edit: misread I didn't see the OFF in that sentence hah
Edited by Trusted cuItivator (08/13/15 02:54 PM)
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blackout


Registered: 07/16/00
Posts: 5,266
Last seen: 2 months, 24 days
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Re: Cook dry grains at high pressure to hydrate and sterilize [Re: thoraxx]
#22087642 - 08/13/15 02:56 PM (8 years, 5 months ago) |
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Quote:
thoraxx said: Are you using metal jars?
No, are you referring to the ones in the picture? those are just cans of food. I have seen in processing plants they will have sample cans of food with wireless thermometers in them, they bury them deep in the stack of tins and sterilize and monitor if the core of that jar has been up to temp long enough.
I have sterilized in aluminium cans though, with the tops cut off, this does speed up heat transfer. I talked about this more and some other ideas in this thread.
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blackout


Registered: 07/16/00
Posts: 5,266
Last seen: 2 months, 24 days
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Re: Cook dry grains at high pressure to hydrate and sterilize [Re: blackout]
#22103314 - 08/17/15 03:56 PM (8 years, 5 months ago) |
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I cooked up some maize as described. It was 1.5kg of dry grain, I washed it and microwaved it while wet until it was reasonably hot. Meanwhile I had a PC on full boil with maybe 3L of water in it. Usually I would have 3 jars with maybe 600-700g dry grain in total. So I am easily doubling the capacity. I could get more in there as I was cautious about it expanding too much.
It came out weighing 2920g which is pretty good, I would usually aim to double the weight, and it should be a little under as some of the initial 1.5kg is lost to washing and dissolved into the boiling water.
It was pet shop maize with lots of broken kernels. I seived out the smaller broken ones but it still had lots left. It did not seem overly starch or mushy though.

It went into boiling water on full power. 12mins in it was at 7psi 14mins in it was at 10psi 16mins 15psi
it remained between 16-23psi for 30mins and was then taken off the heat 46mins into the process.
Coooled down to 0psi in about 15mins, so had an overall heating time of about 60mins.
It was strained and put into a preheated 4.5L container and microwaved for 30mins. The container had water added and was boiled for 10mins, it was also soaked in bleach before this. I microwaved on full for about 5mins to get it back to boiling, and then turn down to defrost to keep it hot without driving too much moisture off. It was enclosed in a plastic bag with the opening loosely tied with several silicone bands. This forms a wet tunnel which incoming air must pass through when cooling, and hopefully grab and contaminants. The microwave is not opened after the first 5mins are finished. Let it cool completely in the microwave.
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36fuckin5
Alchemycologist


Registered: 08/11/03
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Loc: Diving into Mystical Territori...
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Re: Cook dry grains at high pressure to hydrate and sterilize [Re: blackout]
#22103478 - 08/17/15 04:37 PM (8 years, 5 months ago) |
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I used to PC my popcorn all the time. 30 minutes at 15 PSI, after the timer goes off just pull the stopcock and let it vent then drain. Load into jars and PC.
-------------------- Redd Foxx said: If you're offended I don't give a shit and don't come see me no more. Pat The Bunny said: A punk rock song won't ever change the world, but I can tell you about a couple that changed me. bodhisatta said: i recommend common sense and figuring it out. These are the TEKs I use. They're all as cheap and easy as possible, just like your mom.
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blackout


Registered: 07/16/00
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Re: Cook dry grains at high pressure to hydrate and sterilize [Re: blackout]
#22558552 - 11/22/15 07:37 AM (8 years, 2 months ago) |
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The grains pictured above did not work. Seemed like moisture came out of the grains afterwards, maybe the microwave drives it out or something. I did it again and it is working so far. I preheated the grains in the microwave longer this time, and a shorter PC time so they would not hydrate so much.
I did not vent the PC as the grains are submerged and not been heated by steam. This allows me to get to a high pressure/temperature much quicker, if it takes too long the grains will overcook, overhydrate and explode. I preheat the grains in a microwave so they are past 100C, when I pour them in the boiling water it actually causes surges as it is hotter than the water.
975g unsoaked maize heated in microwave until I hear 2 pops (like popcorn) add to approx 3L rolling boiling water in PC, seal, no venting 3mins 5psi 6mins 10psi 8mins 15psi 15mins 20psi 25mins turn off still 20psi 45mins vent at 3psi
1732g afterwards. Put into 3.5L filtered tupperware container, put inside loosely sealed autoclave bag
microwave 4mins full until puffed out as it is boiling and steaming,
30mins on defrost/low to continue boiling without excessive moisture loss.
The 3.5L container can turn on the microwave turntable, my previous 4.5L one cannot so it would not have been heated as evenly. I injected 24ml of LC and it is colonising well.
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Machiavelliavore
Vermiculite Hater



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Re: Cook dry grains at high pressure to hydrate and sterilize [Re: blackout]
#22559075 - 11/22/15 10:56 AM (8 years, 2 months ago) |
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Man, beautiful work you're doing here as always. I really dig this idea of sterilize it inside with the PC, fuck around with it all you want in open air, then kill what's on the outside with a microwave.
Have you tried transfering the substrate from the PC straight to mycobags? It seems like they would be ideal for maximizing the space usage of the microwave if they don't melt. Also even if they got a bit clumpy you could easily break them up by hand.
Is the initial heating of the grains performed in a glass bowl? I tried nuking some dry rice and found that thin pp5 melted quite easily.
--------------------
I spawned some popcorn casings and had double-overlay cause I didn't put enough hydrogen peroxide in my automated aquarium mister. I only got one mushroom so I cut off the head part where the seeds fall from and put it in a jar of LC and sprayed it all over a tin of PF cakes I made with gravel, cardboard, and bisquick in my microwave. I think it will be good cause B+ is so potent. Triggered yet? Only a square would say "a cube is a cube."
No, this does not look right...
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blackout


Registered: 07/16/00
Posts: 5,266
Last seen: 2 months, 24 days
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Re: Cook dry grains at high pressure to hydrate and sterilize [Re: Machiavelliavore]
#22559384 - 11/22/15 12:12 PM (8 years, 2 months ago) |
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Quote:
Machiavelliavore said: fuck around with it all you want in open air, then kill what's on the outside with a microwave.
It could be steamed too, I know many have aversions to microwaves. You could get a big drum and turn it into a steamer with a simple submersed element. You can also use a induction heating plate. In europe large PCs are rare, and if you do find they they are very expensive. Also people might simply not have space for a large PC. The microwave allows you to use large containers and it can be taken out and shook with ease to ensure the core is hot. Some have trouble with large jars stalling but jars are typically tall with filters at the top -while containers are typically shallow so do not suffer this stalling.
Quote:
Machiavelliavore said:Have you tried transfering the substrate from the PC straight to mycobags? It seems like they would be ideal for maximizing the space usage of the microwave if they don't melt. Also even if they got a bit clumpy you could easily break them up by hand.
I have put them in autoclave bags before. If they are not mixed up right they can melt & burn.

They puff up with steam too much for my liking, this is the difference between steaming and microwaving, you are boiling the grains in the bag and they will get hotter than the surrounding air and puff up the bag, while if steaming they do not really puff up. In a PC they will puff up if vented too fast.
The maize works well as it is quite hard and dense, it is like shaking a tub of marbles compared to say RGS which is too light. I have my tubs in autoclave bags so the outside will steam too, also it is sort of like a SAB upon cooling down. I leave them in the microwave to cool down and the inside of the bag is still wet. You do not need autoclave bags, I have used regular plastic bags. When they puff up its a sign the tub is boiling so power can be reduced.
Quote:
Machiavelliavore said: Is the initial heating of the grains performed in a glass bowl? I tried nuking some dry rice and found that thin pp5 melted quite easily.
Yeah, a glass pyrex bowl or a ceramic bowl, it will get very hot so would certainly melt most plastic. I stir it regularly, sometimes with a temperature probe. The popping sound is a good indicator but if you have not stirred the grains it may pop locally in a overhot section while the rest is not hot. After you hear pops I suppose you could stir and put it back in on defrost to heat evenly.
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Machiavelliavore
Vermiculite Hater



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Re: Cook dry grains at high pressure to hydrate and sterilize [Re: blackout]
#22559436 - 11/22/15 12:25 PM (8 years, 2 months ago) |
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Just want to check: Were the melting problems with the autoclave bags with hydrated PC'd grain or dry grain?
Sounds like PP5 tupperware with a generously large SFD would be the way to go for resterilizing PC'd grain in the microwave.
4qt bowls of grains or some such would be very convenient to inoculate, or perhaps even large bowls/15L tubs of PC'd straw + grains.
Man, the dollarstore had these great 4L PP5 bowls. I only got 3 of them, wish I'd gotten more.
--------------------
I spawned some popcorn casings and had double-overlay cause I didn't put enough hydrogen peroxide in my automated aquarium mister. I only got one mushroom so I cut off the head part where the seeds fall from and put it in a jar of LC and sprayed it all over a tin of PF cakes I made with gravel, cardboard, and bisquick in my microwave. I think it will be good cause B+ is so potent. Triggered yet? Only a square would say "a cube is a cube."
No, this does not look right...
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blackout


Registered: 07/16/00
Posts: 5,266
Last seen: 2 months, 24 days
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Re: Cook dry grains at high pressure to hydrate and sterilize [Re: Machiavelliavore]
#22559628 - 11/22/15 01:21 PM (8 years, 2 months ago) |
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Quote:
Machiavelliavore said: Just want to check: Were the melting problems with the autoclave bags with hydrated PC'd grain or dry grain?
It was hydrated grain, but would have dried out locally in the bag and so gotten to very high temps. If it is near the magnetron outputting the microwaves then it can heat up and the rest of the bag is not really heated. The bag would have been so big that it was not rotating on the turntable.
A tip is to get a bit of cardboard and cut it so it fits in the microwave and bring it to the shops to compare it to containers they have.
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blackout


Registered: 07/16/00
Posts: 5,266
Last seen: 2 months, 24 days
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Re: Cook dry grains at high pressure to hydrate and sterilize [Re: blackout]
#22559649 - 11/22/15 01:26 PM (8 years, 2 months ago) |
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found my post about that bag
Quote:
blackout said:
 This was after about 25mins in the microwave on full. 4kg of wet wheat which I forgot to mix up. It was a good 3" from the wall of the microwave where the magnetron was. The autoclave bag melted, most of the bag was only about 40C.
Bags are very good for microwaving in because it is so easy to shake them about. A lower setting also helps as the heat can be conducted throughout the bag.
note it was on full. I would microwave and shake about and when boiling reduce power.
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blackout


Registered: 07/16/00
Posts: 5,266
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Re: Cook dry grains at high pressure to hydrate and sterilize [Re: blackout]
#22563826 - 11/23/15 02:42 PM (8 years, 2 months ago) |
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Put another one on, ended up more hydrated than I planned, so quite a few exploded grains, this was barley and as I said before I think maize (or popcorn) is more forgiving as its harder to hydrate.
1kg dry barley, microwaved for about 10-12mins, a probe in it was 130C, so the grain would have been hotter as it would not transfer heat to the probe very easily. No popping heard.
Poured into about 3.2L boiling water in the PC, again this surges the water as the grain is hotter than the water. Sealed right away again with no venting heating on an electric hob.
0min 0psi 2min 2psi 4min 5psi 7min 13psi 9min 17psi 10min 20psi -power off, left on hot hob 11min 22psi 12min 22psi 15min 21psi 16min 20psi 17min 18.5psi 19min 17psi 22min 15psi 24min 13.5psi 27min 11.5psi 32min 8psi 36min 6psi 38min 5psi -take off still warm hob and put on cool hob 40min 4psi 42min 3psi 46min 2psi -opened and strained Microwaved for 6mins on full then 40mins on defrost/lowest. This is in a 4.5L PP5 container in an autoclave bag which is crumpled up at the opening and loosely sealed with silicone tube acting like an elastic band which makes the bag puff up as it pressurises which signals when you can turn the power down.
weighed 2313g before microwaving so it took on 1313ml or 1313g or water, so this is 131ml water per 100g grain which is a more than most recommend. Excess will be boiled off while microwaving but it resulted in many exploded grains. I expect it may not be shakeable so may need lots of LC to inoculate.
Next time I would do less time. Maybe a quicker cool down time, the heat up time seems pretty good but I have no more control over that, the other option of course is less pressure. It was probably at 15psi at 8mins in and so was over 15psi for 14mins.
Edited by blackout (11/23/15 02:47 PM)
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