In many ways, art of winemaking is art of developing or manipulating four naturally-occurring acids: tartaric, malic, citric, and lactic.
Academically, acidity is measured in pH, a logarithmic scale that measures free hydrogen. Perversely, higher pH, lesser acidity, lower pH, greater acidity.
All wine is acidic, with pH ranging between 3 and 4. Water pH is 7.0, lemonade 2.5.
Simplistically, higher acidity pairs better with food. That is why naturally acidic sauvignon blanc and riesling are food friends. Acidity also balances fruitiness, important in reds. Target pH for whites is 3.0-3.4; reds 3.3-3.6; sweet wines 3.6-plus.
Acidity inhibits wine oxidation, preserves color, increases stability, reduces bacterial growth and bacterial fermentation. Winemakers reverently genuflect to acidity.
Tartaric acid found in wine grapes is not found in most fruit. Tartaric acid reflects soil where grapes grew and grape variety—cabs have plenty tartaric acidy, malbec and pinot noir have less.
Sauv blanc lovers love palate-cleansing acidity. Chardonnay drinkers, not so much. Winemakers deploy malolactic fermentation to convert chard’s tart malic acid into milky lactic acid. Malolactic fermentation decisions and use of oak create range of flavors and styles in chardonnay.
Citrus, lime, and lemon are common acidic references. When natural, wonderful. When wine makers add citric acid to make up for problems, the practice trowels pancake makeup on flawed wine.
Over-ripe grapes in hot-climate vineyards often lack acidity; wine is “flabby.” Cooler climate vineyards boost acidity. Vineyards hot during the day and cold at night are best of both worlds. Think Napa, Washington State, Chile, Old World, New Zealand, Texas High Plains.
• Dancing Bull Sauvignon Blanc 2013. Citrus cascade: tangy grapefruit, pineapple, lemon, lemongrass; clean, crisp, assertive, no-oak bargain. $12
• Franciscan Napa Valley Sauvignon Blanc 2013. Lime, grapefruit, pinch of peach, blade of grass; crisp, citrusy, palate-cleansing acidity. $17
• Merriman Brasher Block Columbia Valley Chenin Blanc 2011. Dry, deliciously crisp, cleansing; pear, lemon zest, elegantly restrained fruit. $25
Last round: The main reason I drink wine is to make other people interesting.
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