Of Oak and Wine (Part II)

As I wrote in my last post, this is a touchy subject with winemakers and wine drinkers alike, especially when it comes to white wines. Oak is almost impossible to avoid, so one needs to know what potentially it is that oak can do to or for a wine. At the end of this post I offer a tasting experiment that I hope will help you form your own opinions about oak.

The two main influences of oak on wine are its wood tannins and the traces of the compound vanillin it releases into the wine. What these and the other elements in oak do is add or enhance aroma, flavor, body, and color. Together they act as what one writer calls “the winemaker’s spice rack.” Depending on your personal tastes, the results can be eitherdivine, a disaster, or something in between.

Oak, as a source of tannin, ranks in influence right after grape skins and
grape seeds. Tannin imparts an astringent, bitter taste, like that of over-
steeped tea. It turns your mouth dry and puckered. It is what makes
young red wines taste harsh, hard, biting, and at times undrinkable.
Over time tannin settles out of a wine. It mellows through oxidation
and the wine turns smooth and (one hopes) beautiful. The deposit you
find at the bottom of older red wines is mostly composed of precipitated
tannin.

Unpleasant as it is, tannin is extremely important for the preservation
and development of a red wine; so it is needed. The trick is to keep it
from dominating a wine for the wine’s entire life. Think of a wine’s
maturation process as a race between its fruit taste and its harsh tasting
tannins to see which will one outlast the other. In a great red wine the
two are so suitably matched the race turns out a tie, even if it takes 15 or
20 years to run, and the results are a richly smooth and glorious wine.

By the way, to partially overcome the effects of tannin in red wine open
the bottle an hour or more in advance and splash it into a pitcher, carafe,
or decanter. The contact with air will oxidize the tannins and soften the
wine’s taste. Just pulling the cork and letting the bottle “breath” is not
enough, because too little air reaches the wine through the narrow
opening. The wine has to be seriously aerated. How long in advance
you decant it depends on the heftiness of the wine, how much tannin it
contains, and personal tastes. Some wines, like a young Italian Barolo
or French Hermitage, can taste even better the next day or two or three
days later. Obviously this is something you need to experiment with, so
I suggest you decant a bottle of young, substantial Cabernet Sauvignon
and then sample it throughout the course of an afternoon or evening. I
assure you it will make as marked a difference as serving temperature
does.

During fermentation white wine does not remain in contact with the
grape skins and seeds for nearly as long as red wine does, so it absorbs
virtually no tannin in the process. The main source for its tannins is the
oak barrels in which it is aged. The tannin in oak is different from that
of grape skins and seeds. For one thing it oxidizes more easily and so
its influence mellows more quickly. But in young or over-oaked white
wines you can often detect a bitterness, astringency, or wood taste that
signals its presence.

Vanillin, the other main element contributed to wine by oak, adds, as its
name suggests, a vanilla taste and smell to wine. As the wine ages, or if
a lot of vanillin is present, the taste can shade towards butterscotch and
caramel. Vanillin gives white wine a butter-cream texture and color. If a
young, healthy white wine has a bright golden-yellowish hue to it that is
a sure sign it has been exposed to oak. As a white wine ages it takes on
a deeper, burnished-gold cast owing to oxidation. If the process goes to
far, or if too much air is allowed to get to either a red or white wine, it
will “oxidize.” The result is it will lose its fruitiness and begin to taste
and smell like dry sherry. White wines turn a dark yellow and red wines
take on brown tinges at their edges. If you are ever served a wine in a
restaurant that tastes or smells of dry sherry and has a suspicious color,
send it back. It’s a bad bottle. (Because oxidation is the most common
cause of “bad bottles,” I suggest that those of you who have not smelled
or tasted dry sherry do so. In sherry oxidation is quite pleasant, but not
in a table wine. Memorize its smell and taste and look out for it.)

Another discernible effect of oak on wine is sweetness, but not that of
refined sugar. How can something be sweet but not sugary? Think of
caramelized onions. Vanilla itself gives the impression of sweetness,
but again without sugar. There are other examples of things that smell
sweet but are not really, for example spices like cinnamon or cloves,
which are fragrances some people find present in oaky wines.

Most often when people say a wine tastes sweet they are reacting to the
affects of oak. Unless we are talking about dessert wines, wines with
actual fruit sugar remaining in them, the vast majority of wines are dry,
meaning all of their available sugar has been converted to alcohol so
there is none left to taste. I realize this is a technical distinction, but it’s
one you should be aware of, especially when discussing wine with a
wine merchant or waiter. If you ask for a “sweet” wine you are liable to
be given something you didn’t bargain for.

Okay, I can imagine there may be some doubt in your minds. So, if you
want to experience for yourself the effects of oak, conduct the following
tasting with some friends. Buy a bottle of Louis Jadot’s Macon-Village,
or Pouilly-Fuisse, or an Ardeche Chardonnay by Louis LaTour. These
are examples of unoaked Chardonnay. For an example of a wine under
the influence of oak, get a bottle of Gallo of Sonoma or Lindemans Bin
65 Chardonnay. Now taste the two bottles you’ve selected side-by-side,
starting with the no-oak wine first. Note the differences in color, smell,
and taste. I’ll not further prejudice the results by suggesting what you
are likely to taste and smell in these specific wines, but I will remind
you there are no “right” answers or responses. Further, you may find
you prefer one style over the other, or you may find you like them both
but realize one or the other might work best in a given situation.

If you want to go one step further and experience the effects of barrel
toasting, then get a bottle of Toasted Head Chardonnay (you’ll love the
label) and sample it against your oaked Chardonnay after you have
finished the non-oaked versus oaked part of the experiment. Remember,
“toasting” refers to the effects of heating barrel staves over a fire in order
to bend them. It can result in flavors that run from toast to dark caramel.
Here you will find the flavors of oak at perhaps their most pronounced.
If you like Toasted Head, then there’s little doubt you’re an “oaky.”

Health note: it is the tannin from grape skins and seeds, called condensed
or procyanidin tannin, that studies have shown to be beneficial to your
heart and circulatory system. So think of red wine as a kind of medicine
and enjoy a glass or two every night without guilt.