Brewing with Oatmeal
Once you get the basics of brewing with barley malt down, it is fun to start experimenting with other grains and adjuncts. In this story, Jamil Zainasheff discusses brewing oatmeal stout. If you want to try homebrewing with oatmeal, take a moment to learn a little bit about how to use it in your homebrews.
What it does
Adding oatmeal to a homebrew recipe is a great way to add a silky mouthfeel — one of the characteristic traits of oatmeal stout, as well as some porters. This happens because oats contribute unique unfermentable sugars to beer that are not found in barley, which are perceived as texture in your mouth.
Partial mash
Unfortunately for all-extract brewers, oatmeal is an adjunct that needs to be mashed, not steeped, in order to perform properly in a brewing recipe. Mashing is the process of soaking grains in a volume of controlled-temperature hot water to convert the starch in the grains into fermentable and non-fermentable sugars. The plus side of this is that brewing with oatmeal is a fun excuse to try your hand at brewing with the partial mash technique.
Types of oats
Oatmeal is available in many different forms: whole, steel-cut, rolled and flaked. Rolled and flaked oats have been exposed to heat and pressure before being dried and packaged, so their starches have been gelatinized, therefore they can be added directly to the mash for the starch to be converted to sugar. Whole oats, on the other hand, which includes steel cut oats, need to be cooked before adding them to the mash in order to gelatinize the starch (which remember then needs to go through the step of mashing). Try to start out brewing with oatmeal by using recipes that call for rolled or flaked oats to save a step — and some of the mess — during the brew day. You can find flaked oats at your favorite homebrew supplier, and rolled oats are available in the grocery store.
How much
Oatmeal is best used sparingly in beer recipes because it can cause a lot of trouble during wort separation as it leaves behind thick, viscous beta glucans. All-grain recipes tend to keep the amount of oats down to around 5–20% of the grist (although 20% is pretty high and not recommended for novice brewers). Ironically, oatmeal does not provide much flavor in beer, so if you want more of an oatmeal-y taste your best bet — instead of adding more oats — is to look for a recipe with specialty grains that provide the types of bready flavors associated with oatmeal, such as Victory® malt. Most well-designed homebrew recipes will keep the oats down to a minimum, so look for reputable sources for recipes (for example, Jamil’s recipe for oatmeal stout on page 20 of this issue.)
Too much oatmeal in the mix can also cause a lot of haze in your finished beer, so it’s a good idea to look for recipes that include Irish moss or another sort of kettle fining agent to cut down on the potential cloudiness.
