Work in the vineyard & cellar

Many stages of work are involved before a finished bottle of wine reaches a consumer.
 

New developments in viticulture and cellar technology during the past few decades have enabled the German wine industry to survive. Thanks to intensive research in recent years, there have also been decisive improvements in the overall quality of German wine. Justifiably, one can say that the amount of really excellent German wine produced today is unprecedented.

Work in the Vineyard
Throughout the entire year a wine-grower has various tasks to tend to, such as training and pruning the vines, soil care, foliage treatment and thinning, as well as harvesting the grapes as selectively as possible. In January or February, the old wood is pruned away, a procedure that definitely influences the potential yield and ultimately, the quality of the wine. The number and length of canes and their shoots also play an important role. Quality-conscious growers generally reduce the number of canes per vine to two short ones or one long one. Many growers have come to realize that today, with a worldwide surplus of wine, quality is a vital competitive factor and quality begins in the vineyard. Vine prunings are usually mechanically chopped or crushed, then worked back into the soil to improve the humus supply. To this day, pruning by hand remains a very labor-intensive task. It takes large estates several weeks to complete this work.

Vineyard activities peak in the springtime. Before bud-burst, the vine's shape takes form through bending and tying the canes in order to ensure an adequate nutrient supply to the shoots. Plowing and seeding for green covering, as well as the natural growth of plants in the vineyard, brings the soil to life. Organic nutrients, e.g. manure, straw or compost, as well as supplementary minerals, e.g. magnesium, calcium or phosphate, are also added at this time. Today, economical and environmental factors play a great role in how vineyards are fertilized. Modern methods of soil analysis easily help determine where there are deficits. Carefully planned fertilization and green covering also help avoid ground water pollution.

"As little as possible, as much as necessary" is the motto of modern wine-growers with regard to spraying to combat vine pests and fungus disease. Starting with healthy vines, i.e. planting vines that have been grafted onto suitable rootstock, for example, also helps reduce the incidence of disease and damage. To help keep the grapes healthy, growers spray them from four to seven times between May and August, depending on the weather.

Another labor-intensive phase begins after blossoming in June. Ideally, the blossoming period, the self-pollination phase that leads to berry formation, is not prolonged. This could result in coulure (blossoming without fertilzation) or millerandage (development of uneven-sized berries). Insufficiently fertilized blossoms wither and/or drop off in windy or rainy weather, and thus, seriously reduce the yield. Removing unwanted shoots promotes growth. Growers also prune clusters in order to reduce yield and thus, improve quality.

Between June and August, a thick leaf wall develops that is kept in shape by tying or binding the shoots. Healthy, i.e. green, foliage is very important for assimilation in the leaves. Nevertheless, some of the leaves must be removed in order to

increase sun penetration and improve air circulation. Leaf pruning in July and August also regulates the height of the vine. Today, this work is usually done by machine.

In July and until the beginning of August there are still means of influencing the quantity and quality of the grapes. Thinning out some of the pea-sized berries strengthens those left on the bunch. More and more growers are using this method to improve quality. Starting in mid-August, the grapes clearly begin to ripen. The amount of sugar in the berries rapidly increases as the acidity decreases (particularly the malic acid; the tartaric acid is retained).

Depending on the summer weather, the harvest begins in mid- or late September. Rainfall at this time is not desired, because at this stage of ripeness, the grapes would absorb the water and the wetness would encourage rot. Growers can measure how ripe the grapes are with the help of an optical instrument, a refractometer, and thus, determine the optimal time to begin picking. Grape variety, vineyard site as well as ripeness all play a role as to when the harvest begins, but the individual growers decide for themselves.

Growers are required to supply the Federal Agricultural Office with harvest-related data, e.g. quantity and origin of harvested grapes, type of harvest and must weights. In flat or gently sloping sites the vines are often harvested mechanically. The grapes for Beeren- and Trockenbeerenauslese, however, must be picked by hand. The law also requires growers to submit a final harvest report, which enables the authorities to monitor total production and, if necessary, deal with surplus production.
Each wine-growing region has specific yield limitations. If a grower exceeds the limit, the surplus cannot be marketed as wine during the following year.

Work in the Cellar
According to the German wine law, wine is a product made exclusively from the complete or partial fermentation of fresh or crushed wine grapes or grape must. It sounds so simple, but before a bottled wine finds its way to the consumer, the cellar master has much to accomplish.

Crushing and Pressing
After picking, the grape vats are unloaded at a pressing station. In white wine production, the grapes are immediately pressed as gently as possible (whole bunch pressing) or destemmed, crushed and immediately, or after a short period of skin contact, pressed. The must is the thick liquid produced by smashing or crushing the grapes.

Red wine production generally involves one of two methods. One is fermentation on the skins, during which the skins are left in the must until sufficient tannins and color have been extracted, then the must is pressed and continues to ferment. The other involves thermal treatment of the must, whereby the juice is briefly warmed or heated to extract color. After it has cooled, the must is crushed and fermented. Today, many growers use a combination of the two methods to produce red wine. In rosé wine production, red grape must is pressed immediately. Weissherbst is one type of rosé wine produced in Germany.

Must Treatment and Chaptalization
After allowing the solid matter in the must (particles of skin or soil) to settle, either naturally (by gravity) or by using a centrifuge or special filters, it's best to remove potentially undesirable elements from the must prior to fermentation. Bentonite (a type of clay) fining, for example, clarifies solids that could cause cloudiness in the finished wine. In vintages with high acids, growers are permitted to to treat the must or the wine with calcium carbonate to reduce excessive acidity. Often, the yeasts that are naturally present in must are unable to cause spontaneous fermentation. For this reason, it is increasingly common for growers to rely upon cultured yeasts to start fermentation. Adding dry sugar (sucrose, i.e. cane or beet sugar) to the must of German Tafelwein (table wine) or simple Qualitätswein (i.e. quality wine without a Prädikat, or special attribute) is permitted, and practiced in France and other wine-growing countries, too. This procedure, known as chaptalization, compensates for insufficient natural sugar in the must (happens in cool vintages, when the grapes do not ripen sufficiently). The added sugar is converted into alcohol during fermentation.
European Union law permits the addition of sucrose, concentrated grape must or rectified concentrated grape must to chaptalize, or enrich, the must.
The amount of sugar that may be added to the must, i.e. the potential alcoholic strength the resultant wine, is strictly regulated by law. The German wine law is not as generous as that of the EU: Qualitätsweine mit Prädikat (quality wines with a special attribute) have to "make it on their own" -  chaptalization is strictly forbidden.

Fermentation
In "average" musts, yeasts convert sugar into alcohol and carbon dioxide (i.e. alcoholic fermentation) within eight to ten days at temperatures between 14 - 20°C (57 - 68°F). In higher-quality musts (with a high sugar concentration), fermentation can take months, e.g. Trockenbeerenauslese. Fermentation can be temperature-controlled (by heating or cooling) or regulated by using stainless steel pressure tanks. This makes it possible to stop fermentation, thereby allowing the wine to retain a certain amount of natural sweetness (in German, Restzucker, or residual sugar). The cloudy beverage in the process of fermenting, i.e. somewhere in between must and wine, is called Federweisser, Bitzler, Rauscher or Sauser (no English-language equivalents). Once fermentation has ended, it is referred to as "young" wine.

Winemaking
After fermentation, the lees (dead yeast cells, insoluble tartrates and other solid matter) fall to the bottom of the cask or tank and are separated from the young wine by means of racking (transferring the wine to another container, leaving the lees behind). Afterwards, sulfur dioxide is usually added, to bind oxidative substances, e.g. aldehyde, and protect the wine from oxidation. Malolactic fermentation is often desirable, particularly in red wine production, whereby lactic bacteria soften a wine's acidity by converting stronger malic acid into weaker lactic acid. The second racking usually takes place in conjunction with fining, during which a fining agent is added to remove any suspended particles left in the wine; the fining agent(s) are removed during racking. 

Residual sugar in a wine can be achieved by interrupting fermentation or by adding sweet reserve (unfermented, naturally sweet grape juice) to the finished wine prior to bottling. Very often, yeasts are unable to ferment all of the sugar in the must of very ripe wines, such as Auslese, Beerenauslese and Trockenbererenauslese. These wines retain their residual sugar naturally.

Aging and Bottling
Aging - the storage time in cask and/or in bottle - can decisively influence the quality and flavor of a wine. Consumers today seem to prefer young, fresh wines. As such, white wines are often bottled and marketed after minimal aging. On the other hand, high- and highest-quality wines are aged much longer before being bottled. Red wines and whites from the Burgunder, or Pinot, grape varieties are increasingly aged in small, new oak casks (Barriques).
Depending on the size of an estate, most bottling today takes place on semi- or fully-automated bottling lines that vary in size and capacity. Bottles are sterilized to ensure total cleanliness and after filling, immediately closed with corks or screw caps. After this, the wine should be stored at a moderate temperature for a few weeks before being shipped. Capsules and labels are added right after bottling or when orders are placed.