One acre in a vineyard can produce 5 tons of grapes, which is almost 4000 bottles of wine. Each bottle of wine uses 2.4 pounds of grapes.
Wine making is an exact process, from the harvesting of the grapes, to fermenting the wine, and finally to the aging of the wines - in oak, or in
stainless steel vats or both.
It is said that around the world wine grapes are harvested in almost every month of the year. Because of the different climates, and type of grape required, wine harvesting is largely dependent on the ripeness of the grapes. There is no way to tell by looking at a grape on its tree if it is at the exact ripeness required, so winemakers use a refractometer to measure the amount of sugar (acidity) in the grapes. Then, they can decide if the grapes are ready to harvest for the type of wine they want to produce. Sometimes, they harvest the grapes a a point of not quite ripe to help maintain the acidity in wine.
Also, important is the grapes tannin ripeness. This can only be determined by tasting the grape, and as such; takes skill and experience to decide if the tannin is ideal for the grapes required.
Ultimately, both these factors are decided based on the style of wine they want to make. Harvesting the grapes is done by hand or with a mechanical harvestor. Although mechanical harvesters are able to harvest more tons than a human picker, there are some examples where they are not used; such as on steep hillsides, or when grapes need to be in perfect condition for the wine they are making, or they need to be carefully selected for their ripeness or matureness.
A machine can harvest 80-200 tons of grapes, in a 24 hour cycle, whereas a human is only capable of picking/harvesting 1-2 tons. Mechanical harvesters are more cost efficient.
The self propelled grape harvester is driven up and down each row of grape trees. It literally rides over the trees, and the grapes are shaken from the branches, falling into the machine holding compartment. When the machine reaches it peak capacity, the grapes are transferred to another vehicle for transportation to the production area where they are sorted and prepared for the fermentation process.
The crusher stemmer machine, can squish the grapes and at the same time remove the stems from the grapes.
In winemaking, grapes are fermented in order to make them into alcohol. This is done by adding yeast to the grapes.
The winemaker must decide on the type of yeast to use in the grapes. There are many different types. Many winemakers prefer to use a predictable cultured yeast.
The cultured yeasts most commonly used in winemaking belong to
the Saccharomyces cerevisiae (also known as "sugar yeast") species.
The yeast used is what makes each wine different, even it is the same grape varietal. The winemaker also needs to decide on the sugar content to have in the grapes, and the fermentation temperature. All these contribute to the final wine product.
The temperature used can enhance or suppress certain flavours and aromas in the wine.
While fermenting, the yeast needs a continuous supply of vitamins, minerals, phosphorus, sulfur, nitrogen, and carbon. These are all naturally present in the grape, however, their quantity may need to be adjusted by adding to them during the fermentation process. For this requirement in the fermentation process, wine makers can buy time release nutrients, which are made specially for the wine industry.
The fermentation process will halt when: the yeast has ceased its process of fermenting the grapes evident by either all the sugar being converted into other chemicals or when the alcohol content in the grapes has reached a per unit volume of 15%. At this point, 15% alcohol, the concentration is enough to halt all strains of the yeast process. Winemakers can also halt the fermentation at any point by adding cold temperature to the vat.
Aging wine helps to give it a much better flavour. Winemakers age many wines at least for a time, usually anywhere from a few months to 3 years. Pricer wines are usually aged the longer times. Both white and red wine can be aged. Common methods for aging a newly made wine are by using oak barrels(usually French or American Oak), and stainless steel vats. Some winemakers use one or the other, while others may use a combination of oak and steel vats to age the wine.
Some labels will say the amount of time of aging a wine has had but not all countries do so. Some wine regions are required by law to include the information on the label. And in some wine regions like Spain for example, the name on the wine label tells what type of aging the wine has had.
Tempranillo, a red spanish wine, is aged for a length of time. The least aging in oak is 6 months, and the most aged time in oak is 2 years. For labelling purposes; a label that read simply Rioja, or Rioja Tempranillo, means the wine has had the least aging required, where a label that reads Rioja Crianza, means the wine has had 1 year oak aging and 1 year non oak aging, and Rioja Reserva means it has had 1 year oak aging and 2 years non oak aging, and Rioja Gran Reserva means the wine has had 2 years in oak and 3 years non oak aging.
Many bought wines are meant to be consumed soon after purchase. These are known as 'young' wines. Other wines, usually more pricey selections can be drunk soon after purchase or they can be aged for years.
You can usually find information about aging a wine in the wine's tasting notes. This is available at many online wine websites and wine makers websites.
Collecting and Aging Wines
Many wine drinkers collect wines. There are different reasons for collecting wines. Some collect wines to age them and then sell them for money, while others
age them only to have their own wine collection.
Wines can age for 5-10 years, and some from 10, 20 or more years. The best wines for aging are those with high acidity and structured tannins, as well as low alcohol. Typically, 13% or less alcohol is good for aging. And, those with sweeter character can age even longer, like Riesling, Port, Sherry.
Some good examples of white wines for aging are quality German Riesling, sweet Chenin Blanc(Loire Valley), White Cotes du Rhone(France), White Bordeaux(France), White Rioja(Spain), Muscat, Burgundy Oaked Chardonnay, and Chablis(France). For red wines; Cabernet Sauvignon, Temprannillo, Sangiovese, Bordeaux Blend, Malbec, Cabernet Franc, Grenache, Chianti, Reserva Rioja. Most of these reds and whites can age 5-10 years.
Red Bordeaux(France), Douro Reds(Portugal), some Tempranillo(Spain), some Sangiovese(Italy), and most Cabernet Sauvignon(many countries) can age 10-20 years. For white wines; Chablis, Sauternes, Ice wine, late harvest Riesling, and Rutherglen Muscat.
When buying wines, lesser priced wines are not ideal for aging. Usually mid priced wines are good candidates for cellaring. Look for wines in the $30, $40 or more price ranges. Red wines tend to have better aging potential than white wines.
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