Though barley is the foundation of beer, homebrewers love to add their favorite non-grain fermentables to their batches. You can add some pretty crazy stuff to your beer when you’re homebrewing (trust us), but here are some of the most popular styles:
Though pumpkin and/or pumpkin pie spices can find their way into many beer styles (pumpkin porter, pumpkin wheat), a "pumpkin beer" is commonly an amber ale tipped towards the malty end of things. These beers may feature spices commonly associated with pumpkin pie, like cinnamon, nutmeg, or clove, or they may actually use pumpkin in the brewing process. Using pumpkin in beer has a long history in the US, dating back to colonial times, when barley was scarce and all types of squash were used to provide additional fermentable sugars. Squash contains starch, which must be broken down into simpler sugars for yeast to consume it. By adding baked pumpkin to the mash in all-grain or partial-mash brewing one can break these starches down, but be aware that this will make the mash sticky and more difficult to sparge.
Fruit beer can be a refreshing twist on a timeless drink. Fruit beers themselves have a long history; the sour lambics brewed in Belgium since the middle ages often have sour cherries added to make what is known as a kriek, and several other fruits are now commonly used with lambic, such as raspberries. More modern fruit beers follow a similar formula to the lambic: a crisp beer with good fruit aroma, little hops, and some noticeable tartness. Some brewers add real fruit to the end of the boil or to the secondary fermentor. Others use fruit extracts at bottling, which allows them to add it to taste and fine tune the amount of fruit flavor and aroma.
These are uncommon (for obvious reasons), but adventurous brewers will add chile peppers to a pale lager or ale base. The peppers can be added to the end of the boil, secondary, or to the bottles for a nice presentation/warning sign. Whatever method you use, quite a bit of heat is going to get into the beer, so be careful about using hotter peppers. Jalapeno is probably the most commonly used.
With so many stouts and porters being described as “coffee-like”, it’s no wonder brewers decided to take the resemblance a step further by adding coffee to beer. Stouts and porters commonly get this treatment because of their roasty characteristics, but coffee can add interesting flavors and aromas to almost any style. The world of coffee is almost as varied and nuanced as beer is, so there is a lot to choose from when selecting a bean. Most brewers tend to steer clear of heavily acidic varieties, and aim for smoother coffees with good roasted notes. The coffee can be brewed strong and added into secondary or at bottling, or it can be ground coarsely and added to secondary like dry hops.
Close in concept to the coffee beer, the chocolate beer seeks to enhance the chocolate flavors from some malts by adding the real thing. Chocolate can be added in a variety of forms, from normal chocolate bars (be careful with bars that have unknown ingredients), to bakers chocolate, cocoa powder, pure cacao nibs, or chocolate extract. The chocolate is usually added to the boil or the secondary. In either case it can turn into sludge, but with careful racking you'll be left with only the chocolate flavor.