First attempt with steam infusion

Cookiebaggs · 04-26-2007, 03:00 AM

Well, after reading the numerous threads on steam infusion mashing, I was sufficiently interested enough to build my own system.

I was able to cannibalize my parents pressure cooker that they had used for canning salmon but have not used in a long time. It had a 1/8 inch NPT thread already tapped into the lid for the gauge so retrofitting a shut off valve was just a simple matter of buying a nipple, a tee, and 1/8 inch ball valve.

I was able to get 1/4 inch rigid copper with 90 degree and tee fittings to construct a manifold for my 10, gallon square Coleman drink cooler along with the flexible high temp silicone tubing.

I will attempt to step mash a 10 gallon batch of Octoberfest on Saturday. I am using 27.75 lbs of grain at a 1.12 qt per lb ratio. (all I could fit with dough in at 104 degrees)

As a precaution, I have two mash schedules. One for the steam infusion and one for a triple decoction if the steam system fails to work properly. I will follow with pictures of the setup and a report on how things went.

Special thanks to Brewman, flyguy, Yuri, and kladue for posting their experiences and ideas. You guys rock!

rdwj · 04-26-2007, 03:08 AM

Keep us posted. I'm interested in building a steam setup, but would like to hear all of the experiences I can before diving in.

Cookiebaggs · 04-26-2007, 03:34 AM

I'll definitely let you know how things go.

I did a trial run on the system with 5 gallons of water at 70 degrees and found out a few things.

1.) The pressure cooker on the stove really couldn't heat the water with the steam at 20 for crap. The pressure in the kettle dropped rapidly with the valve wide open and the water moved up only 2 degrees from 70 to 72.

2.) A bigger heat source, my burner, made a huge difference in how the system preformed with only water. I was able to open the valve part way at 20 and keep a sufficient source of steam at a constant pressure of 15 and heat the water up to 130 in 10 minutes.

3.) After the water in the MLT reached 140 degrees, all the water was blown out of the manifold and pure steam just cranked out of the holes. I believe this was because the copper finally heated up enough to blow the liquid out of the lines. The "hopping" sound of the manifold stopped after I hit 140. I was now pushing all steam through the manifold.

Of course all of this was with water. Add the thermal mass of the grain and I'm sure the steam will perform better with a lower heat source, a higher starting temp (104) and a smaller temperature rise between steps.

FlyGuy · 04-26-2007, 03:35 AM

Hey, that's great. I will be really curious to hear how you make out.

Just a word of caution -- I suggest trying out that system first on 10 gallons of water. I am not sure how large a pressure cooker you are using, but my little 1.5 gallon pressure cooker might have some difficulty with a 10 gallon batch. Brewman ! or Yuri could probably tell you from the specs of your pressure cooker and heat source how well it would work on a big 10 gallon batch.

If it were me, I might try with a 5 gallon batch first, and see how things go. Or at least, if the 10 gallon batch doesn't work, be mindful that there are limits to using a pressure cooker, and you might have to go to a bigger steam system like brewman ! or Yuri.

Anyways, good luck and I will be watching carefully to see how your brew goes!!

Cookiebaggs · 04-26-2007, 03:41 AM

I have a 4 gallon pressure cooker and I put about 2.5 gallons of water in it for the test.

Thanks flyguy! But that's why I have the triple decoction mash schedule ready to go. If I fail to raise the first temp from 104 to 122, I'll just pull decoctions and go from there.

**Yuri_Rage** · 04-26-2007, 03:45 AM

The fact that you were getting liquid out of your manifold tells me one of two things:

Either you had the pressure cooker too full, and it need to vent some of that water off before you got steam (which can be dangerous - water doesn't "give" as easily as steam in the event of over-pressurization).

OR

Something I've found when initially heating my system is that I have to purge the pressure several times before I have usable steam. I'm assuming that the air inside the boiler expands and pressurizes the system before the water is up to temperature. If I allow it to continue heating without purging, it exceeds my target pressure of 10-12 psi while the water is still relatively cool.

Welcome to the world of steam!

Cookiebaggs · 04-26-2007, 03:49 AM

I guess I mis stated, I wasn't ever getting liquid out of the manifold, I just never got the whole thing to blow steam until I reached about 140. I had steam coming out of the holes that were closest to the hose connection all the time.

FlyGuy · 04-26-2007, 03:50 AM

Quote:

Originally Posted by Cookiebaggs

I have a 4 gallon pressure cooker and I put about 2.5 gallons of water in it for the test.

Thanks flyguy! But that's why I have the triple decoction mash schedule ready to go. If I fail to raise the first temp from 104 to 122, I'll just pull decoctions and go from there.

You will definitely be able to raise your mash temp, but it will just be a question of how long it will take. And the bigger the mash, the longer it will take.

With a 4 gallon pot, I bet you will be fine. And yes, you DEFINITELY need a good heat source to drive all that steam pressure. I noticed a 30% difference between two similar-sized burners on my stove (one must not heat as well as the other).

One more thing -- Yuri's caution about not over-filling the pressure cooker is a very good one. But if you under-fill the pot, you won't have enough 'thermal inertia' to quickly raise the mash temperature. Brewman ! has worked all that out. I hope he chimes in, too.

FlyGuy · 04-26-2007, 03:56 AM

Quote:

Originally Posted by Yuri_Rage

Something I've found when initially heating my system is that I have to purge the pressure several times before I have usable steam. I'm assuming that the air inside the boiler expands and pressurizes the system before the water is up to temperature. If I allow it to continue heating without purging, it exceeds my target pressure of 10-12 psi while the water is still relatively cool.

I noticed the same thing, although I never put it together until you mentioned this. Thanks Yuri.

Another potential reason to purge the air out of your pressure cooker/boiler prior to heating the mash is to vent out any oxygen.

**Yuri_Rage** · 04-26-2007, 03:57 AM

I misunderstood you when you mentioned water vs steam in your earlier post. Good job on the system, by the way!