Just follow the steps to produce red and white wine. Actually, it's not that simple. In fact people devote their life to making wine. Perhaps you can join in, start by reading this wine trivia.
The subsections appear in chronological order: starting with the soil, grafting and training the vines, the temperature, harvesting the grapes, fermenting them, and finally pressing them. As almost always, some items don’t neatly fit these categories. We start with planting, discussing such issues as soil and temperature, two factors that can make or break a crop.
Grapevines do not consistently reproduce from seed, but are grafted onto rootstock. Because of phylloxera, a devastating louse originally imported into Europe on American vines during the second half of the 19th century, European grape varieties (Vinus vinifera) are grafted onto American rootstock such as Vinus lambrusca.
Wine grapes grow best in relatively thin topsoil with good drainage and water retention. Rich soil usually leads to bland, poor wines.
Warm soils such as gravel, loam, and sand hasten the ripening process, while cold soils such as clay delay it. Dark, dry soils are warmer than cold wet ones.
In an apparent paradox alkaline soils, such as chalk, stimulate the production of grapes with a relatively high acid content.
To optimize output, producers generally plant vines farther apart in fertile soils than in poor ones.
Twenty years ago a typical acre in a California vineyard contained between four and six hundred vines. Today this same acre may contain between six hundred and almost three thousand vines.
An untrained vine grows wildly in all directions. Training the vine along a trellis supports it, and enables the grower to determine the amount and positioning of both leaves and fruit. In the hands of an expert, such control improves the quality of the grapes, even while reducing their quantity.
Newly planted grapevines usually require four to five years before yielding a commercial crop. With proper care and luck, they may continue producing a viable crop for fifty or one hundred years, or more.
Wide temperature variations help create a balanced wine. Those cool nights in torrid zones such as the Duero River region in central Spain keep the grapes from ripening too rapidly and enable them to retain a pleasant acidity. In contrast, hot areas that don’t cool down enough at night usually produce flabby wines that lack acidity.
On the other hand, unseasonable temperatures lead to multiple problems such as grapes budding too soon or too late. When vines in a given vineyard are at widely different states of maturity they are difficult to maintain and to harvest.
Why grow grapes if you can’t bring in the harvest? Here are a few suggestions for picking the grapes and then pressing them.
Prior to harvesting, many growers thin or remove the canopy of leaves at the top of the vine. This increases the grapes' exposure to the sun and hastens their ripening.
Excessive water, whether from irrigation or a dreaded downpour right before harvesting, swells the grapes and dilutes their flavor.
In an apparent paradox, spraying vines with water may prevent the grapes from freezing. The water freezes into a thin coat which protects the entire plant from additional freezing. Sometimes producers want the grapes to freeze, producing Ice wine (Canada) or Eiswein (Germany and Austria.)
While a trained individual may pick 2 tons of grapes a day, a mechanical harvester can pick 40 to 100 times as much.
A major advantage claimed for hand harvested grapes is more careful handling. Sharp-eyed workers won’t pick unripe or otherwise unsatisfactory grape bunches. Many of the finest wines in the world such as Chateau d’Yquem Sauterne are hand picked by people in a series of rounds.
Mechanical harvesting increases the likelihood of broken grapes, which may reduce the wine quality. This problem is more critical for white wines.
On the other hand, some growers claim that mechanical harvesting of grapes provides a more uniform crop since they are picked within a short time frame. Another advantage is that the grapes may be harvested at night: the potential benefits of doing so are discussed next.
Picking grapes on cool nights increases their acidity, reduces their oxidation rate and slows the rate at which grape skins color the clear juice.
While sugar levels help determine when grapes are ready for harvesting, it’s essential to wait until the tannins are mature. Immature (green) tannins can create an astringent wine and may prevent it from aging properly.
Once the grapes are harvested they must be pressed and fermented. A small mistake, and all may be for naught.
The more gently the grapes are pressed, the lower the quantity of juice extracted, but the better its quality. The juice with the best flavor and the optimum balance of acidity and sugar comes from the pulp located between the grape seeds and the skin. The harder the grapes are pressed, the greater the quantity of juice extracted from less desirable pulp located near the skin or near the seeds.
The human foot is ideally suited to crushing grapes. Manual treading breaks the grapes, mashes the skins, and mixes them with the juice but doesn’t break open the grape seeds that would give the wine a bitter taste.
The extremely slow interaction of oxygen and wine ages and hopefully improves the wine. Size matters: Wine matures more slowly in large bottles than in small ones, because the larger the bottle the less oxygen per volume of wine.
Temperature matters: When the fermentation temperature exceeds 90ºF (32ºC) or falls below 38ºF (3ºC), the yeast can no longer do their job and fermentation slows to a snail’s pace or stops.
Wine is fermented in barrels filled to only about three-quarters full. This reduces loss due to foaming of the fermenting juice when the temperature reaches 70ºF (21ºC) or more.
Warm or hot fermentations add toast and vanillin aromas and flavors while diminishing fruity aromas and flavors. The classic examples are red Chateauneuf-du-Pape wines of the Rhone Valley in France.
Generally, cool temperature fermentations are very slow and produce fresh, lively, fragrant wines. The classic examples are white Rieslings from the Mosel Valley in Germany.
A moderate wind cools and dries grapes, reducing the likelihood of mildew and rot, especially for varieties such as Pinot Noir and Sauvignon Blanc, whose grapes grow in close-fitting clusters. But too much wind can interfere with photosynthesis, or break the vines.
Fining agents such as egg whites, gelatin, and even bull’s blood, remove suspended particles from wine before bottling.
While European oak is split, American oak is sawn. Sawing the oak breaks open the wood cells, and releases aromatic substances such as vanillin.
American oak is kiln-dried, whereas most European oak is seasoned outdoors for several years. This seasoning leads to the loss of both positive aromas and negative tannins. You don’t have to be a professional wine taster to distinguish the aggressive American oaked wine, and the more subtle European oaked wine.
Grapes used for Icewine must be completely ripe with clean, unbroken skins. They actually freeze on the vine. Harvest time usually starts in mid-December, around 3 o’clock in the morning.
Not only Icewine producers hope for frost. A little bit of winter frost hardens the vines and kills parasites in the bark.
The color in red wines comes from grape skins. The longer the skins soak in the fermenting mixture, the darker the wine.
A wine’s degree of color often indicates its intensity of flavor. Opaque dark red wines are usually heavier and more flavorful than translucent, lighter reds.
A pale color with green highlights may indicate a wine from a cooler growing area; one that is often pleasantly acidic.
Excess moisture leads to mold, in particular for varieties such as Pinot Noir and Sauvignon Blanc, whose grapes grow in close-fitting bunches.
Grape skin is the major source of wine’s color, flavor, and tannin. Small grapes such as Pinot Noir produce the most concentrated, flavorful wines.
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Wine is chock full of interesting and often surprising facts, factoids, and statistics. Some would call it trivia, but this wine information is hardly trivial. Spark up your next wine tasting party with wine information.