So What’s the Deal with Mashing vs. Steeping Grains?

Why can some grains be steeped while other must be mashed?  What’s the difference and how do you tell which are which?

Base grains have only been kilned dry.  So they need to be mashed – combined with hot water at specific temperatures to activate enzymes in the grain.  This converts the starches into sugars that the yeast can eat.

The steep-able specialty grains are kilned and or roasted while still moist.  The combination of moisture and heat basically results in mashing the grains inside the husk.

What happens if you just steep mashing (base) grains?

Depending on the temperature of the water and the amount of time – you may get some of the starches to convert into sugars.  But the remaining starch will stay in the beer through fermentation, giving you a nasty case of starch-haze and possibly some off flavors.

Oh great – so how do I know which grains need to be mashed?

Unfortunately there’s no way to tell by looking at the grain, its name or the label on the package.  Its one of those things you just have to learn.

For the most part – base grains are named after a place like Pilsner, Munich and Vienna – regular old 2-row or 6-row “pale” malt – and anything that isn’t barley (rice, corn, wheat, oats or rye).  All of those need to be mashed or used in extract form.

The steeping grains you’re probably familiar with.  Crystal/Caramel and Chocolate Malts, Carapils, Roasted Barley and Black Malts.

But then there are those sneaky ones.  The ones that sound like specialty grains and aren’t available as extracts.  Acid, Brown, Melanoidin, Mild, Smoked, Special B, Speacial Roast – mash them.

Is there a list or something?

Of course!  Here are a couple.

The first, and I think best, is in one of my favorite home brewing books – Brewing Classic Styles (p. 15-17).  It has a great table of nearly all of the grains you will find in the home brew shop and a bit more technical detail about what goes on at the maltster if you’re interested.

Brad over at Beersmith also publishes the ingredient list from his most excellent brewing software – which you can view here.  It has a little more detail about each of the grains (click on the name for additional description).

A quick google search will turn up several more lists – and the good people at your homebrew store should be able to keep you on track if you’re not sure.

Eventually you’ll get a feel for which ones are which.  If you  move to partial mash or all grain brewing you won’t have to worry about it since all of the grains get mashed together.

Next Tuesday we’ll talk about what’s involved in doing a simple stovetop partial mash to get you started.  Be sure to bookmark this page or subscribe via RSS or email so you don’t miss it!

Tagged as: base malts, homebrewing, mashing, specialty grains