Author Topic: Infusion and Step temperatures - Q  (Read 6541 times)

thirstynomad

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Infusion and Step temperatures - Q
« on: October 18, 2010, 01:17:31 PM »
Hi there -

Can someone validate my understanding please?!

Infusion = The water temperature at the time it leaves the kettle
Step temperature = the temperature of the infusion water, mixed with the grain

So, if a recipie is saying to add 1.6 gal of water @ 200F, step temp is 168F and step time is 10min - i take that to read as i mix 168F water and existing mash for 10 minutes?

Thanks

Offline MaltLicker

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Re: Infusion and Step temperatures - Q
« Reply #1 on: October 18, 2010, 08:26:26 PM »
http://howtobrew.com/section3/chapter16-1.html

Well worth reading.

The strike water, ~200F, mixed with 68F grain, lands at the step (or mash-out) temp of 168F, for example.

In BeerSmith, these numbers are in the Mash Profile dialog box.

Offline CR

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Re: Infusion and Step temperatures - Q
« Reply #2 on: October 20, 2010, 09:50:58 AM »

Infusion = The water temperature at the time it leaves the kettle
Nope.

There are a couple ways the word infusion can be used.
1.) As a Noun: Infusion is the end result from steeping any plant matter in  a fluid substrate.
The fluid can be hot old water solvent it does not matter . Infusion is what you get after you did the steeping.
2.)  As a Verb: In brewing it's often used to describe the process.   So the infusion is the process of the steeping  of grains in hot water.   IE: Single Infusion process.  You only steep the grains once and only at one temperature.   

Multiple infusions are spoken of because of the "rest" which was to me a confusing term.  It's not a friggin rest to my way of thinking it's a Temperature HOLD POINT.      I would guess that the term rest may stem from  old school brewers who used direct heat usually in the form of a fire to raise the mash temperature it was a rest during which they could cool their heels before the work of feeding the fire began anew.  It could be some romantic crap about the grains having a little rest and  a spot of tea.  It may also just be the word they settled on.   I don't know.
But all it  amounts to is a thermal hold point Each of which are the actual mashing processes. 

 
Quote
Step temperature = the temperature of the infusion water, mixed with the grain
Nope.  The steps are the various thermal hold points. 
Most modern malts (read: pretty much every single malt you can buy without going out of your way top get an older variety) are modified and have a diastatic power (read: lots of enzymes)that is more than sufficient to convert all the starches. ALSO: most all modern malts have undergone the lower temp conversions during the malting process  because of that diastatic power.

This all means that you really have only three choices to make:   Whether to do a protein rest or not and what temp to select for your  Single infusion mash. Lower temps like 149 - 151 F and the higher temps in the upper 150s  each produce  different results.  Depending on the base malt the difference may - or not - be substantial. 

Quote
So, if a recipie is saying to add 1.6 gal of water @ 200F, step temp is 168F and step time is 10min - i take that to read as i mix 168F water and existing mash for 10 minutes?

Ahh you must be thinking about the mashout & sparge?
Fhugetaboutit~!!
Mashout is a friggin joke. It's a hold over from the bad old days of unmodified malts.
You can sparge at any temp you like (within reason).  Batch sparging is my method.
The 168 - 170 F temperatures of mashout & sparge are to accomplish two things: (a) denature the enzymes with heat and (b) dissolve any remaining stubborn sugars.   For my money the only reason that's worth a damn is (b) because you gonna boil the wort right away and  that'll kill the enzymes deader than the dodo.
How much stubborn sugar will you get?   Prolly nill, but like an OCD I  use a higher temperature to sparge anyway.

The only think to keep in mind is that you don't want too much heat and certainly not too much time.
In fact that's one of the dangers of trying to do a step mash. The excessive time it takes to do the step transitions may end up  making your beer bitter and astringent.

Do you drain the wort from the grain bed before adding the 200 Degree Water?

Well yah. your Mash Tun is only so big.
You can do the math to calculate the thermal masses and see how much energy and mass you gotta add to it to raise the temp by X amount.  OR you could look at the mass and temps and just guess about whether the 1.6 gallons of 200 Deg water will move 5 gallongs of weater appreciably.

Yah drain the wort.