I love craft beer, but am not too familiar with the brew process. Was wondering how some beers get some of the flavors they do - specifically those like toasted coconut, caramel, and toffee (which I love!) I know barrel aging can create incredible depth and breadth to a beer's bouquet, but I doubt they're sprinkling coconut into the barrels! How do those flavors get in there?
Toasted coconut, caramel, and toffee tend to come from the malted barley -- that's my oversimplified answer. There's quite a bit of chemistry that goes into the longer, more complex answer, and I'm not 100% positive about all of the nuances of it, so we'll skip that. Other flavors, like esters and/or phenols (think banana, clove, and the like) tend to be produced by the yeast. There are MANY other sources for the flavors, some of which overlap, like adding a citrusy hop and an additive like lemongrass, for example.
Where to start. Caveat, I do homebrew. Generally, the sweet flavor in beer comes from the grains. Depending on the malting process and even the smoking of the malts, you can get many different flavors. The standard malts are 2 row and 6 row, but you can go to carapils (for caramel) or all the way to black patent (for super bitter and dark). Two, yeast is factor and can promote anything from a dry, crisp flavor to banana/clove to tropical fruit to the ever popular horse blanket depending on the strain. Three, hops add a variety of flavors. You use hops early in the boil to add bitterness. Latter in the boil for aroma and flavor. And, you can dry hop for more flavor. Depending on the hop varietal you can get spicy/peppery, tropical fruit, pine, citrus, berry, grape, and host of other flavors. Four, you can add pretty much anything else you want to flavor the beer. I have used seeds of paradise and lemon zest. You can also add fruit juices, whole fruit, chilies, dandelions, and pretty much anything you can think of to impart flavors. In the end, what you use depends on the attempted style. Homebrew literature has some interesting insights if you like to read: http://www.howtobrew.com/section4/chapter19.html
Toasted coconut comes from aging beer in a toasted barrel. There are no grains that provide a coconut flavor or aroma. It can also come from coconut although this is less common. Caramel comes from various types of Caramel (Crystal) malt. It provides some malty sweetness too. Toffee also comes from Crystal malt, usually the medium-dark variety. British Crystal malt seems to produce the best toffee flavors. American Crystal malt is less toffee-like. The comparable Belgian and German malts provide a similar, but different caramel or toffee flavor that I find to be more toasty.
