Oak Barrels, Chips or Extract?

Winemaking at home gives you the freedom to make your wine any way you want: thick heavy reds, light fruity rosés, crisp elegant whites, all made to your style. The use of oak, in the right amount, can turn an average wine into a prizewinner. Oak's delicate vanilla scent and complex toastiness enhances the fruit flavours and aromas already present, forming a complex bouquet. On the other hand the inappropriate use of oak can damage a delicate wine beyond repair, and an oak overdose can take so many years to die off that the wine passes from youth to maturity to feeble old age before the strong woody flavors are softened enough to make it drinkable.

Your first decision will be whether to use oak at all. Commonly, only full-bodied red wines and richly flavoured whites like Chardonnay and Sauvignon Blanc are treated with oak. Also, because oak can give an intense flavour impression, only premium wines are treated; 28 day kits probably don't have enough flavor to balance the addition of oak and less expensive juices like Chablis or French Columbard aren't helped by oaking them. When in doubt, ask a seasoned wine-maker what he/she recommends. Your next decision will beto choose a form of oak. Several things will influence your decision: the amount of money you want to spend, how much room and how much wine you have, and the what type of oak flavour you want.

Barrels are harder than carboys to use, handle, maintain and keep clean. But the extra effort will be well rewarded, because a good barrel can make a tremendous difference in the quality of your wine. To a red, it conveys a softness and complexity that adds great character, due to the conversion of harsh tannins to softer polymers; to some whites - particularly Chardonnays and similar wines - it can give additional aromatic qualities that make the wine special. Two weeks in a barrel can mature a white wine as much as a year in a carboy would have done, and in the process confer a delicate but attractive oakiness that announces the wine as truly "commercial" in character.

How Barrels Are Made
Barrels are constructed of many separate, fitted pieces of wood - called staves - and end pieces fitted in a circular shape. All of these pieces are forced together (usually being bent while heated) and held in place by a series of metal hoops.
No nails or other fastening are used, except for a few tacks to hold the hoops in place. In essence the barrel is waterproof because the pieces fit tightly against one against the other. When the barrel is filled with liquid, the wood swells slightly, effectively completing the seal.

French and American barrels
Barrels are typically made of oak (although some other woods, such as redwood or cedar, are sometimes used), with the very best oak considered to be that from the French forests of Limousin and Nevers. In the French method, the staves are split from the timber using an axe, piled in stacks in the open and allowed to season for 1 to 2 years. Exposure to sun and rain results in the sap being thoroughly removed. After this time the rough staves are individually shaped by the cooper, one barrel end is constructed, and then the staves are made pliable by being placed over a low fire. When the heat has done its work the staves are bent into place and the first hoop fitted. The process is repeated at the other end, and a second hoop fitted there. The third, fourth, fifth and sixth hoops, each pair progressively larger than the previous, are placed at alternate ends and driven tightly up the staves, then tacked in place.
The traditional American practice was to saw the staves from the timber, dry them in a kiln, and then form them into shape using live steam. This certainly made the whole process a lot faster, but it was found that wines aged in them exhibited an excessive "green wood" or sappy quality. For a number of years this was ascribed to the use of American, rather than French, oak.
The French method of construction produces a softer result, a fact based on the internal structure of wood. Wood, being produced by a living plant, is composed of a series of cells. These are long and tubular, and are all aligned in the same direction. When the wood is split, it naturally cleaves along the grain, revealing only the sealed outer surface of the cells. Air drying allows all of the sap to be removed, and softening it over low heat results in a slight browning or "toasting" of the wood surface.
In the traditional American manner, when the wood is sawed, it is equally possible that the surface will be cross-grain, exposing the cut ends of the cells. Consequently any liquid placed in it - such as wine - will itself be exposed to the bitter material within the cells themselves. In addition, kiln drying, rather than removing the sap, may tend to seal it in, and steam heating confers no equivalent to the light toast of the European barrels.

How Barrels Make Better Wine
When a young wine is placed is placed in a barrel, a number of things occur. The first, and most important, is that the alcohol in the wine leaches from the wood a number of complex tannins and vanillins that enter into the flavor profile of the wine (this is the primary reason why cross-grain wood is undesirable).

The rate at which the leaching occurs depends on the strength of the wine and on the age of the barrel - in other words, the number of times it has previously been used - since that will obviously affect the amount of tannin left in the wood and the depth at which it is found. The greater the age of the barrel, the longer wine needs to remain in it, in order to obtain a given level of oakiness.

On thinking about it, one will conclude that the surface area of the barrel is important as well, since a larger surface area means more wood surface from which to extract tannins and vanillins. If you remember your high-school geometry class, you will recall that as a container (a cube, sphere, or what have you) increases in size, the volume increases faster than the surface area. This means that smaller barrels have a larger surface area, compared to volume, than do larger ones, and therefore that smaller ones confer oakiness faster than do larger ones.

Barrel Alternatives
Other easy ways to oak your wine

If you'd rather not buy a barrel, there are easier and less expensive ways to add oak to your wine. One is the use of oak extract to simulate the barrel oak; another is the addition of oak chips to the wine, and the third is "oak sticks" of toasted French oak to place in the wine.

OAK EXTRACT: Of the three, oak extract is the least satisfactory. It creates some oak flavor, but if enough is used to be truly noticeable it may leave a harsh taste. It is, however, fast and easy to use. Extract is produced commercially by steeping oak in alcohol, which is then bottled. OAK CHIPS: Oak chips give a bit more oak flavor. It is possible to buy high-quality French oak chips - actually, oak shavings rather than the cheap sawdust - from Nevers, Limousin and other French oak forests. Here's a tip: If you do use oak chips, rinse them either in water or (preferably) sulphite solution before putting them in the wine. This will remove loose sawdust particles that can be difficult to separate from the wine.

OAK STAVES: The best of the three is "oak staves." If these have been properly produced they are split, not sawed from the lumber, with smooth surfaces on all sides. Typically, they're about one Inch Square by about one foot long. They should be sterilized by rinsing in a strong sulphite solution (similar to the one used to precondition a new barrel), then split lengthwise using an axe into smaller pieces to increase the surface area available to the wine. This will produce a noticeable oakiness not unlike that from a barrel and has been referred to as "putting the barrel in the wine, rather than the wine in the barrel."