Difference betwen Partial Mash and Extract with specialty malts

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Delaney

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Hi,

I want to understand the difference between extract recipes with specialty malts, and partial mash.

I recently brewed a batch of Chocolate/Coffee porter. I steeped my specialty grains @170F for 30 minutes, then I began 60 minute boil.

https://www.homebrewtalk.com/f12/chocolate-coffee-porter-extract-263619/

The only difference I can see between what I did and what a partial mash is, is that I steeped for 30 minutes at 170F vs. the 45-60 minutes @ 155F seen in most partial mashes.

Was I not converting starch into sugar with my chocolate/coffee porter? Is this a partial mash or extract with specialty malts.
 
What makes a partial mash is doing an actual mash with some of the grains. The key to a mash is using grains that actually "do" something during the steeping (mashing). That means using grains with diastatic power, like two-row base malt, Munich malt, pilsner malt, etc. The way starches convert to sugar is by enzymatic activity. Without using malts that have these enzymes, all you're doing is steeping.

Crystal malts are made in such a way that they are pre-mashed, so to speak. So you get all they have to give by steeping them. But grains like biscuit malt, Munich malt, maris otter, etc are NOT treated that way. They must be mashed in a prescribed amount of water (so you get the correct pH) for a prescribed amount of time for the enzymes to work on the starches.

All of the grains in your recipe are steeping grains. Even if you left them longer, you wouldn't get any enzymatic activity. They'd just be wet for a longer period of time.

A partial mash is easy, and cheaper than all-extract brewing. 5 pounds of two-row can replace three pounds of dry extract- saving at least $5 just in that cost. I recommend trying it!
 
THe difference is simple, with extract with grains, you are simply steeping the grains to get some flavor and color from them. In a partial mash, you are mashing a part of your grainbill and that is providing a number of fermentables (converting the starch to sugar,) which you are then rounding out with extract to make up your starting gravity.

Take a look at my Old bog road brown ale recipe, in the recipe I give you all the variances from extract with grain, through several partial mash permutations based on how much grain you fell comfortable mashing all the way up to an all grain recipe. You can see pretty much that the "specialty grains" (in the case of extract with grains, what you steep) stays the same throughout the recipe, what changed is the amount of extract and/or base malt. Hope this helps.

:mug:
 
But grains like biscuit malt, Munich malt, maris otter, etc are NOT treated that way.

All of the grains in your recipe are steeping grains.

I am definitely going to try a partial mash next time and cut down on liquid extract...Basically it adds 15-30 minutes and a mashable mat type.


But I did use 4oz. biscuit...


Thanks for the help.
 
okay so assuming 1.5 quarts/# of grain for a partial mash.

Do I consider the specialty malts in the grain bill as well???
 
okay so assuming 1.5 quarts/# of grain for a partial mash.

Do I consider the specialty malts in the grain bill as well???

Yes. And you want to add enough basemalt to convert the other grains. So figure a pound of two-row for every pound of "others", as a ballpark.

In order to convert grains like biscuit malt, oats, etc, you have to have enough Diastastic power (DP) from some other malt with DP like two-row.

Say you have a pound of crystal malt, .5 pound biscuit malt, and .25 pound of Munich malt. Munich can convert itself, but doesn't have enough DP to convert other grains. So, toss in 2 pounds of 2-row (1.5 pounds minimum, but for "even" sake, I said 2 pounds) and you've got yourself a PM. 1 pound crystal + .5 biscuit + .25 Munich + 2 pounds two-row = 3.75 pounds grain. Mashing with 1.5 quarts/pound plus sparging with up to .5 gallons per pound (or up to your boil volume) will convert the biscuit and ensure conversion of the Munich malt.

If you want to decrease the amount of extract in your batch, keep in mind that 1 pound grain = .75 pound LME = .6 pound light DME (roughly).

Some brewing software can really help with calculations when you get to this stage, as well as give you info on which grains can be steeped and which must be mashed.
 
As Yopper noted, Crystal is already fully converted, and steeping is just 'dissolving' and rinsing the sugars.

But most other steeping grains, such as Chocolate and Black, do have some starch in addition to converted sugars, and you can get a lot more out of those grains by mashing as opposed to steeping.
 
As Yopper noted, Crystal is already fully converted, and steeping is just 'dissolving' and rinsing the sugars.

But most other steeping grains, such as Chocolate and Black, do have some starch in addition to converted sugars, and you can get a lot more out of those grains by mashing as opposed to steeping.
Good to know, thanks.

Now suppose I want to use specialty grains that must be steeped, but I am brewing a partial mash wort. Should I steep the grains by adding at about 155F during the last 30 minutes of my mashing schedule?
 
I am currently limited by the size of my brew kettles. They are both 2 gallons, therefore at 1.5 Quarts/# grain that allows 4.9# of grain/kettle.

I'm thinking about steeping my specialty grains in one kettle, and mashing my base malts in a separate kettle. I would do a 60 minute hop schedule in 2 gallons of mashed wort, and I would blend the 2 gallons of specialty malt wort at flameout. This would result in more base malt being used, and less extract.
 
Good to know, thanks.

Now suppose I want to use specialty grains that must be steeped, but I am brewing a partial mash wort. Should I steep the grains by adding at about 155F during the last 30 minutes of my mashing schedule?

No. All of the grains go in together. You don't separate them out.
 
I'm doing my first partial mash brew next weekend and can't wait. This thread help with a lot of my questions thanks.BUT....I'm an extract brewer and have a question. Do you still top off with water or must you do full boils when brewing this way.I have a 5 gallon pot and not exactly prepared for full boils yet.

Sorry for the high jack on this thread.....
 
I watched one of Bobby From NJ's vids the other day and I thought he had a nice summary of this topic.
 
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I'm doing my first partial mash brew next weekend and can't wait. This thread help with a lot of my questions thanks.BUT....I'm an extract brewer and have a question. Do you still top off with water or must you do full boils when brewing this way.I have a 5 gallon pot and not exactly prepared for full boils yet.

Sorry for the high jack on this thread.....

You can do partial boils.
 
Thanks, its pumpkin time baby cheers!!

If you're doing a partial mash pumpkin ale, I STRONGLY recommend this recipe. I brewed it last weekend and took a gravity sample yesterday. It already tastes amazing. I can't wait for it to finish.

Edit: The partial mash conversion is a couple posts down from the original.
 
vtron said:
If you're doing a partial mash pumpkin ale, I STRONGLY recommend this recipe. I brewed it last weekend and took a gravity sample yesterday. It already tastes amazing. I can't wait for it to finish.

Edit: The partial mash conversion is a couple posts down from the original.[/QUOTE

Thanks for the tip, can't wait to brew in Sun.
 
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