The Basics: Hot vs. Cold Weather Wine

25 03 2011

I suppose this goes without saying, but the climate of a wine-growing region can have a profound impact on the resulting wine.  At its core, wine is an agricultural product, and even though there are a number of steps producers can take during the winemaking process to put their stamp on the flavour of their wares, much of what ends up in a bottle of wine is determined by the environment in which the grapes are grown and is locked in by harvest time.  This is useful for people trying to make wine-buying decisions, because it means that if you have a little knowledge about the general climatic conditions of the place where a bottle is from, you will be able to get some solid hints about what’s waiting for you inside.

Barossa Valley, Australia -- definitely a hot weather region.

Hot weather wine regions like California, Australia, South Africa and the Rhone Valley in southern France have warmer temperatures, more intense sun and a longer growing season than cold weather wine regions like Germany, Austria or Champagne (or, for that matter, Canada).  As a result, grapes grown in these warmer areas are generally able to ripen more fully than grapes grown in cooler areas.  As a grape ripens, its internal sugars build up and increase, but its natural acids decrease — if you’ve ever bitten into tart, underripe fruit, you have experience with this.  Both sugar and acidity play key roles in the resulting wine:  acidity gives structure and energy to the wine and keeps it from tasting loose or flabby, while sugar is the source of another critical wine component, alcohol.  During fermentation, the grape’s sugars react with yeast to create carbon dioxide (which, apart from sparking wine production, is released into the atmosphere and doesn’t form part of the final wine) and alcohol.  There is therefore a direct correlation between the amount of sugar in a grape and the potential level of alcohol in the wine made from it:  the riper the grape, the more alcohol there can be.

Putting this all together, here are some general hot vs. cold weather wine rules:

  1. Acidity: Hot weather wines = lower acidity; cold weather wines = higher acidity.  You can detect acidity in a wine sometimes by its taste (tart or sour), but also by the mouth-watering/cheek-puckering effect it has, the tingling it causes on the sides of your tongue and the general precision and refreshing quality it brings to a wine.
  2. Alcohol: Hot weather wines = higher alcohol; cold weather wines = lower alcohol.  The 9.5% alcohol German Riesling I reviewed last night is a perfect example of this rule:  it is inconceivable that a wine with that low of an alcohol level would come from a warm weather wine region.  You can detect alcohol in a wine mainly by the warming feeling it generates on the palate (much more obvious in high-alcohol spirits like scotch whisky, but also noticeable in wine to a lesser extent).
  3. Body: Hot weather wines = heavier body; cold weather wines = lighter body.  The body of a wine refers to its weight in your mouth, how thick, heavy or viscous it feels.  Lighter-bodied wines have a similar weight on the palate to skim milk; heavier-bodied wines more closely resemble whole milk or cream.  A wine’s body comes from the level of dissolved solids from its grapes, which is largely (but not completely) affected by their sugar level.  High-alcohol wines tend to be full-bodied, since they come from riper grapes with more “stuff” (sugars and other compounds) in them.

Now THAT'S cold.

Of course, these rules are not ironclad, since hot weather wine regions can have cooler pockets within them and vice versa, but they are a good starting point.  An even less ironclad rule:  Old World (a.k.a. European) wine regions tend to lean more toward the cold weather side and New World (a.k.a. non-European) wine regions tend to lean more toward the hot weather side.  That’s a gross overgeneralization, but it is true that Old World wines usually have higher acidity, lower alcohol and lighter body than their New World counterparts.

OK, enough classroom stuff for now.  Back to the drinking tomorrow.



Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: