Oak's Balancing Act
by Jason Petros
Originally appeared in Zymurgy May/June 2008
Oak has been used in brewing for many years, but recently it has seen a resurgence of interest due to its large flavor impact on both wine and beer. In the past, the oak
flavors gained from storage in wood were considered to be a secondary benefit. Now, with the popularity of stainless steel fermenters and storage tanks, brewers and
vintners alike are able to use these flavors as a creative addition to their products.
When used properly, oak can lend the most beautiful, full and rich properties of the wood and weave them delicately into the beer. When used improperly, oak can destroy the balance that you have worked so hard to achieve, and can taste like you are chewing on tree bark. A little knowledge on what oak is all about can be the difference between turning a good beer into an award-winner or lawn food.
What exactly happens when you put oak in beer?
Oak is full of many flavorful and aromatic compounds and chemicals that, when added to beer, create another level of depth and complexity. Examples are furfural, which lends caramel sweetness, or eugenol, which is clove-like. Vanillin, the most recognizable flavor, tastes and smells like vanilla. Lipids, which constitute the oils, fats and waxes found in the wood, are responsible for oak lactones, which lend coconut and aromatic wood flavors. These are the basic flavors found in all types of oak, and the ones we as brewers are looking for. The important thing to think about when choosing oak for your beer is, ?How will these flavors interact with the flavors already present?? Knowing which type of oak contributes which flavors is key in matching beer to wood. The three most common types of oak are American, French and Hungarian, each with its own balance of flavor and complexity. American oak has a great aromatic sweetness along with a nice vanilla component. It provides a sweet and full mouthfeel to beer, easily paired with most malt combinations. French oak also has an aromatic sweetness as well as providing a full mouthfeel, along with cinnamon and allspice characters. It is widely praised for its sweet spice and ?confectionary? flavor compounds (custard, butterscotch, milk chocolate). Hungarian oaks are said to provide a high amount of vanillin properties, along with roasted coffee and bittersweet chocolate characters. The flavor profile of oak is enhanced during the toasting process. Which compounds come out in what ratios depends largely on the variety of oak and the level of toast it received, ranging from light and untoasted to dark and heavy. When the oak is toasted, the characteristics unique to that varietal are brought out and defined.
For example, American oak at a light toast level will lend a fresh wood and coconut character to your beers, but as toast levels increase to medium/medium-plus levels, these flavors are decreased and more vanilla and caramel notes are brought forward. Medium-plus is typically the best of all worlds in dealing with toast levels, as it brings out the qualities you would normally find in a heavier toast, without diminishing the vanilla and other ?softer? qualities found in a lighter toast. There are many different oak delivery methods, including aging your beer in a full-size barrel, and using sawdust or barrel replica kits. Oak chips and oak cubes are the simplest for homebrewers to use. A barrel is not feasible for many homebrewers, as they require a lot of hard work tokeep them in good working order (clean, stored properly and bacteria-free). Sawdust can be hard to work with and will take some extra time to drop out in your beer, not to mention its lack of complex flavors. Staves and other barrel replica kits are geared more for use with large barrels that have lost much of their oak impact, and are often too large to be used easily in carboys. Chips and cubes, however, are very ?user friendly? and do not need any sort of extra attention or care like their larger counterparts do.
Wednesday, September 28, 2011
Remember when I wrote an Article?
A couple of years ago I wrote an article on using oak in beer. My friend Shea Comfort helped me with the sciency stuff, God Bless him. Anyway, here it is. Read it, print it and line your bird cage with it, whatever.