Partial mash vs extract with specialty grains
 

So I've been under the impression that I've been doing partial mash but apparently I'm actually doing extract with specialty grains.

My first few batches had me heat about 2 gallons of water to 160, add grains, cover and steep for an hour maintaining that temperature, pour wort through filter and colander into bucket, sparge with a gallon of 170 degree water and then return to brew pot.

After reading Sam Calagione's Extreme Brewing book he recommended placing grains in a grain bag and placing in the brew pot with 4 gallons of water, turning on the heat, allowing water to heat to 170 (stirring occasionally) and then removing grains once a temperature of 170 is reached. Obviously this method is much easier as I'm not pouring the wort through strainers and dealing with the mess of grains but I've been told that this is not partial mash.

Is there any difference in the results? Without knowing all of this, I concocted a recipe with a half lb of chocolate malt, crystal malt, and roasted barley and steeped them as Calagione instructed. Will this method work with the grains I used?

Any info is appreciated.

With a partial mash, the only thing that is different than a steep is that you are using grains that will convert their starches into sugars while in a steep, you are using pre-converted grains. So, if you used malts like crystal, chocolate, roasted, etc, you did a steep. If you used Munich malt, maris otter, Vienna, etc, you could be doing a partial mash.

The key for conversion in the grains that need mashing is that the proper amount of water is used for the proper amount of time. It's not the method, exactly, which can be very much like you describe, but instead the ingredients and the prescribed amount of water.

Since you used steeping grains (no conversion), you did an extract with steeping grains batch.

Hope that makes sense!

Makes sense. Thanks. So how do I know which grains are for steeping and which are for mashing. I'm assuming the method of turning off the heat and removing the grains at 170 will work for grains that need to be mashed, correct?

Generally, yes. For the mash, you want to ensure your grain/water mix stays at 150-155, so you can even start at say 162, to make sure you don't go too high, and THEN you add the grains. For a partial mash, you want 1.5 quarts of water per pound of grain, and you want to hold it for 45-60 minutes. When done, you can lift out the grain bag and pour 170 degree water over it (in a colander) to get to your boil volume. You can do the same technique for partial mash and extract with grains.

The only way to know if your grains require steeping or mashing is to learn them, or to google them if you're in doubt. We can always help, too! I have some brewing software that has a little ! next to grains that must be mashed, which helped me learn them.

In general, anything with the words "crystal, caramel, chocolate, cara-anything" don't need to be be mashed. There are others, too, but those are the main ones.

Well, it will work for the same purpose as steeping the specialty grains, but doesn't really qualify as a mash. A proper mash brings the grain and water mix up to around 152 °F for between and hour and 90 minutes, typically. This allows the enzymes in the base malt to convert the starches into fermentable sugars.

I suppose, depending on the quantity of grains and how long it takes you to reach temp, you could get OK conversion by just bringing the grains up to 170°. So, in a sense, you are mashing, but not by the common definition.

How do I determine how long to mash? Is it just a matter of personal preference?

Generally, an hour is standard for a mash. Less time means less conversion, but usually you don't get much more by going longer than an hour and you can start extracting tannins and other not so tasty compounds from the grain if you go too long.

I highly recommend reading the sections about mashing at How To Brew to get a good idea on the process. It's a great place to start for things like this.