Wine Chemistry 101 Feb 8

We often speak of liking our wine “dry” but what does that really mean? The opposite of dry in this context is sweet. And we often prefer one over the other. Don’t confuse fruit with sweetness, though. A completely dry wine may have wonderful fruit character.
The chemistry of wine making that applies here is that natural sugar in the grapes turns to alcohol as it ferments. The longer the fermentation takes place, the more sugar turns to alcohol. When all the sugar has been chemically changed, the alcohol content is fairly high, 12% or higher. Certain wines drink better sweet, so the process is halted before the “residual” sugar is gone. Wines below 12% tend to have some sugar left and we described them as sweet. At 9%, they can be positively cloying. The wine maker controls the final product by measuring the sugar level in the grape (called the “Brix”) and then timing his process to his desired level of dryness or sweetness. If you know you prefer dry to sweet, or the opposite, keep an eye on the alcohol listed on the bottle. Big Shiraz or Cabs come in at 14%. Many whites, including Rieslings, go both ways, from 9% to 12% or higher.