Partial Mash vs Extract w/ Speciality Grains

**AnOldUR** · 12-28-2007, 07:11 PM

I guess I’m a slow learner. Read a lot on this but still don’t quite get it. I plugged my last batch, an Imperial IPA, into BeerSmith as an Extract type. After brewing, the OG came out a high, 1.094 instead of the 1.087 estimate. After reading more about partial mashes I start to think that may be I got some fermentables from the grains. So, I go back to BeerSmith and change it to Partial Mash and the estimated OG comes out spot on the 1.094 that I read.

What I did was steep the grains in 1 ½ gallons of water for one hour at 150-155 degrees and rinsed with ½ a gallon of 170 degree water. I added one pound of Light DME to it and used this 2 gallons for my boil (plus hop additions.) I followed that with a late addition of LME. Here are the grains:

¼ lb Honey Malt
½ lb Carapils
½ lb Caramel 40º L
½ lb Munich 10º L

So here’s the question. Did I do a “partial mash?” If so, what makes it a partial mash and not “extract with specialty grains?”

The only disappointing part is that the IBU’s go from 80 to 68, but it’s still in the range for a IIPA.

**Orfy** · 12-28-2007, 07:42 PM

The key diference is steeping removes flavour, colour and any sugar.

Mini mashing converts the startch to sugar first then does the above.

**AnOldUR** · 12-28-2007, 08:17 PM

Do you get the same amount of sugar either way?

**Yooper** · 12-28-2007, 08:26 PM

Well, no. In your case, you used Munich malt which must be mashed. And then of course, when you mash it you get the fermentables. Steeping grains gets some color and flavor out.

I think there is a chart somewhere floating around on which grains must be mashed and which can be steeped. To really add some confusion, some grains (like munich malt) can convert itself. That is, it has enough diastatic power to convert itself. Some grains need a base malt to help it along. Here is some good reading on this: http://www.howtobrew.com/section2/chapter12.html

I think we also have some great info on the wiki about this, too!

discgolfin · 12-28-2007, 08:57 PM

Part of the premise of Partial Mash is that you replace your extract with a base grain to get the fermentables from this. From what I see these are specialty grains. You can get fermentables out of them but if you mash them. beer smith is giving you different values becasue it assumed you got fermentables out of these grains..Which u didn't rather u got color and flovor. how much LME late was added?

I would keep beer smith as extract.

Jay

**Yooper** · 12-28-2007, 09:03 PM

Quote:

Originally Posted by anoldur

The only disappointing part is that the IBU’s go from 80 to 68, but it’s still in the range for a IIPA.

Oh, and if you did the late extract addition, you didn't reduce the IBUs. Run it through Beersmith as a partial mash to get the expected OG. Then, remove that late extract addtion and see the IBUs. That would be closer to your real IBUs, depending on what time you actually added the LME.

Does Beersmith have a late extract addition option? If it did, that would be perfect!
Edit- I see that it does! In your recipe, double click on the LME that you added late. About 1/2 way down in the box is the "Late addition option". check that box and put in the number of minutes you boiled it. That will correctly figure the IBUs for you.

And you definitely did a partial mash, since you used grains that can be mashed.

Poindexter · 12-28-2007, 09:16 PM

Quote:

Originally Posted by YooperBrew

And you definitely did a partial mash, since you used grains that can be mashed.

And you 'steeped' at a reasonable mash temp, with clearly outstanding results.

Congratulations and enjoy your beer.

**AnOldUR** · 12-28-2007, 09:42 PM

Yooper

I did use the late addition option in BeerSmith, so I think the IBU’s are correct. If the Munich did cause conversion, I’m thinking that the additional fermentables would lower the hop utilization.

Quote:

And you 'steeped' at a reasonable mash temp, with clearly outstanding results.

BeerSmith has it as 75% efficiency. Is that possible with this technique?

**TheJadedDog** · 12-28-2007, 10:42 PM

Okay, it sounds to me like you were intending to steep; however, by leaving the grain for an hour and by using some Munich (which will convert) you unintentionally started to mash (although you did not finish).

Steeping is usually done for only 20 minutes and without any base grain. Mashing is done for an hour with base grain comprising the majority of the grain used.

Jamo99 · 12-28-2007, 11:04 PM

I thought that specialty grains were kilned to convert starches to sugars already. It results in more unfermentable sugars (leading to that sweet caramelness) but also fermentable sugars. Either way, the specialty grains adding that sugar, both fermentable and unfermentable, is taken into account by Beersmith. See this page for a chart of the gravity points that you can expect from some specialty grains.

I'm not sure why the values would change when you change the technique in the program. Anyway, you should go partial mash, you're doing it anyway!