The wine making process begins with the decision to pick the grapes. Although it may seem simple, there are many factors that contribute to this decision; weather is the most important contributing factor. If it is too hot, the grapes have to be picked at night. If a long period of rain is expected, the grapes may have to be picked before optimal maturity levels. Early frosts can have a devastating effect as well as early freezes. The grape variety, combined with wine style, will determine the pick dates. The ripeness of the grape is analyzed and judged. It is then checked for sugar level, acidity levels, pH, color, health, seed color, aromas and flavors.
   Once the decision has been made to pick, containers are placed into the vineyard and the picking of that grape variety begins. At some vineyards, everything is picked by hand and arrives at the crush platform within eight hours of being picked. It is of great importance that the grapes arrive freshly picked. The processing starts immediately; the grapes are visually checked, weighed, and then processed.
   The fresh grapes are tipped out of the bins and placed into the destemmer. As the name suggests, the machine removes the stems because there are astringent, bitter and tannic compounds in the stems that can transfer to the juice or wines if left in contact too long. Once destemmed, the grapes are pumped to one of three vessels (including the press) depending on the grape variety and style of wine to be made.
   White aromatic grape varieties receive up to 24 hours of skin contact. This affects a greater release of phenolics and other compounds from the skin of the grape. (It is in the skin that most of these aromas and flavors are stored.) With red wine varieties, the skin also contains the color pigments. To release the color, the red wine grape varieties are actually fermented in their skins. A combination of heat, alcohol and natural acids extract color from the grape skins.
   At some point, all the grapes pass through the press. The function of the press is to extract the grape juice or wine from the skins and seeds of the grape. In the case of non-aromatic varieties or champagne-base wines, the grapes are either destemmed first or placed directly into the press. In the case of aromatic varieties like Muscat Ottonel, they are pumped directly into the press after 24 hours of skin contact.
   Fermented or fermenting red wine grapes are either pumped or dumped from bins into the press. The first juice or red wine to leave the press is classified as the free-run because it leaves the press without any mechanical pressure being placed on it. This juice or wine is always separated and represents the best portion of the pressing. Depending upon the wine style and winery, the second pressed juice might be kept separated and treated for high phenolics or blended away.
   White wine "must" is cold-settled and racked fresh from the press. This removes any grape skin particles that might have traveled with the juice from the press. The result is a clean grape must which is ready for fermentation.
   The process of fermentation involves the metamorphosis of grape juice to wine. Yeast creates the wine by metabolizing the grape sugars. It digests and breaks down the sugars which then form into carbon dioxide and alcohol. Pure cultured yeasts are selected for their influences on each individual grape variety. Some yeasts do not metabolize color and are best suited for red wines. Other yeasts can tolerate the cold and are great for cold cellars or white wines.
   Once fermentation is complete, racking begins. Racking is the process in which the yeast that has settled to the bottom of the barrel is removed. The wine is pumped out of the barrel or tank, leaving the yeast behind in the bottom of the container. This process may take place several times before the wine becomes clear. Racking can take place a week or years after fermentation, depending on the style of wine that is being made.
   Fining is the process in which unwanted natural substances, like excess protein or tannins, are removed. These substances are removed because they may cause the wine to be cloudy or may give it an unbalanced taste.
   Cold Stabilization makes the wines “tartrate stable”. In wine, there are two main types of acid; malic and tartric. These acids are in abundance in the grape juice, but become less soluble in the presence of alcohol. The higher the alcohol, the less soluble the acid. Potassium and calcium combine with the malic and tartric acids, producing a white crystal. If left uncontrolled, these crystals can form and precipitate in the wine bottle instead of the tank. Often referred to as "wine diamonds", these crystals are often processed into cream of tartar and used for cooking.
   Filtering takes place in many different ways. Some wines are ready to bottle right from racking and aging. Others require diatomaceous earth (DE) filtering, pad filtering or micron filtering. DE filters are very gentle and work on a sieve principle. Filter pads work on absorption and micron filters, which filter out extremely small particles, also work on the sieve principle. Micron filters are also known as police filters because they screen bacteria and yeast cells.
   From the time the last grape arrives in the fall to the time when the wine is ready for bottling, many years of work have past. Filling the bottles, corking, capsuling, labeling and palletizing are the last steps to finishing the wine. Red wines often mature for years before being sold. White wines tend to come to market earlier. Wine is made up of over a thousand different minerals, vitamins and other components and once in the bottle, the wine continues to mature and improve.

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