Oak has a lengthy history in winemaking, and was particularly important before the widespread introduction of stainless steel in wineries in the latter half of the 20th century. It was (and still is) used as a fermenting, maturation, and storage vessel in winemaking.
Oak barrel fermentation is mostly practiced for white wine making (as it's very difficult to extract the skins and other solid mass after red wine fermentation). The process is thought to provide more integrated oak flavors into the wine.
Now here is the thing about oak...popping your wine in oak barrels is not an inexpensive activity, particularly if the oak is new and from France. So what is a humble winemaker to do?
Since the early 1960's there has been a number of other options. Today for example, If you don't fancy spending money on barrels, in corresponding rising of cost, you can filter oak dust through your wine, or use oak chips, or opt for oak staves. These methods have been particularly popular with New World wine producers.
How can you tell if a wine has been produced in this fashion? If a back label refers to the fact that the wine is oaked, but doesn't specifically make use of the term "barrel/s", it's a safe assumption that oak chips or the like have been used in the winemaking process.
How much cheaper are these solutions? Well in the case of chips, it's less than a twentieth of the price of barrels. This is course makes this a an enticing alternative!
It doesn't stop there however. All types of oak (from dust to barrel) can go through a process known as toasting. In essence this is a firing process that comes in three degrees: light, medium and heavy. In varying levels, this toasting imparts a roasted quality into the wine. High toasted wines have a very obvious smoky, charred scent, which can give you many clues in a blind wine tasting.
There are also many different types of oak for the winemaker to choose between. As well as France, America, Russia, Slavonia, Bosnia and Herzegovina all produce oak for winemaking. France and America are however the two best known, and both produce a very different type of oak.
American oak from Minnesota, Wisconsin, Pennsylvania, Ohio, Kentucky, Mississippi, Missouri and Oregon are all highly respected. Unlike European oak, American oak is sawn, not split. This opens up the oak's wood cells, which, in conjunction with kiln drying, (European oak is seasoned outside for many years) means American oak imparts a more pronounced character on its wines.
Winemakers are famous for mixing and matching oak and stainless steel to suit their requirements and the style of their wines. They may decide for instance to mature 30% of their wine in high toast new French barrels for 1 year, with the remaining proportion kept in stainless steel vats. Alternatively the winemaker could mature their wine in 1 year old American oak for two years.
Although French oak is regularly used in many top end wines in America, American oak is not in widespread use in Europe, with one notable exception. Rioja producers prefer American oak as they appreciate its coconut-like scent and the more aggressive characteristic it gives their wines.
So what is the future for oak? Whilst so much is in flux in the world of wine, from wine additions and ameliorations to enclosures, it's unlikely that we're likely to see many significant changes here in the near future. Expect wine's love affair with oak to have a rosy future, for the time being at least.