Winemaker's Archives -- George Troquato

Ripeness: It's All Relative

A ripe cluster
waits to be picked.

Winemakers and vineyard managers the world over are faced with a nagging question come harvest time: When do we pick the grapes? Most vintners of yesteryear relied on taste testing to reach that decision. With more options available, today's winegrower employs a combination of taste, laboratory analysis, and deductive reasoning.

Technical background:

• With hundreds of thousands of taste buds, the human tongue is capable of sensing bitterness, saltiness, acidity and sweetness.
• Brix scale - name after its Austrian inventor, a graduated scale for sugar solutions that represents a percentage of sugar by weight at a specific temperature.
• refractometer - an instrument for determining an index of light refraction (and ultimately degrees Brix) as it passes through grape juice.
• sampling - the process of selecting a representative portion of an entire grape crop for analysis (Some choose 150-200 single berries; Cinnabar selects 15 pounds of full clusters.)

The discussion of wine grape ripeness begins with stylistic trends. When leaner, tighter wines were in style, winemakers picked grapes at lower sugar levels. "Today, we want more of everything," says Winemaker George Troquato, "... aroma, flavor, mouthfeel, color and extraction, and riper tannins." To attain that, grapes are allowed to remain on the vines a little longer, further ripening the fruit to acquire the desired characteristics.

A refractometer used to
check grape sugar samples.

Winemakers wait for several key indicators before harvesting. "The vines should look stressed," says George. "The leaves are slightly darkened and appear fatigued." Second, he looks at the condition of the seeds and stems. At the peak of their ripening cycle, grape seeds turn brown in color and their stems darken. The seeds are also detached from their membranes (i.e. the seeds appear to be floating inside the grape). Next, he checks the Brix of his sampling with a refractometer. For most vintages, he likes to harvest chardonnay and pinot noir at 25-25.5º degrees Brix, cabernet sauvignon at 26º, and merlot at 26.5º.

Returning to the basics, he smells and tastes the sample juice. "The juice of ripe grapes smells very aromatic," says George. "It shouldn't smell green or unripe." As for taste, it should be honeyed, spicy, viscous, rich and powerful, but not green, astringent or tart. "There shouldn't be any off-flavors either," adds George.

For red varieties only, he also looks at the color of the juice. Under-ripe juice is reddish brown while ripe juice is pink to deep Burgundy pink.

As is typical of most grape growing principles, a balanced plan is usually the most effective. While laboratory analysis provides scientific evidence, a keen sense of smell, acute taste buds, and the ability to observe the key indications of ripeness are ultimately as important. Want to make great wine? Start with great vineyard property and finish with a winemaker who has wine stains on his lab coat and mud on his tires.