Any “white” (green, pink, peach, thin variated, as well as some red to black skinned) variety of grapes that has clear-ish to pale lemon-yellow-greenish pulp can produce a “white” wine. Most “white” grapes do not need a lot of time in the sun to reach 24 Brix. 90 days of sun is average and therefore in the Northern Hemisphere, are usually harvested around mid-September. The Brix is tested with a hydrometer. Once the Brix is at the desired sugar level, the winemaker is ready to harvest. To prevent the skins from influencing the color of the wine, the grapes are harvested and then immediately gently pressed. White wines tend to feel lighter in mouthfeel. Most whites ferment and age in steel. Whereas wines aged in oak become influenced by the oak. The barrels allow for “Angel’s Share, meaning that the barrels allow for as much as half a gallon to a gallon per month of evaporation (depending upon humidity). What is evaporating is water. Thus, wines aged in barrels tend to have fuller mouthfeel than light wines that tend to be aged in stainless steel. White wines tend to be simpler, that is you will only taste the primary aromas and flavors such as citrus or stone fruits, without much secondary flavors such as vanilla and clove which come about in oak aging. White wines are typically meant to be consumed young (within a few years) before tertiary aromas are formed from long term bottle aging.
Fermentation usually happens in stainless steel. That is the yeast eat the sugar and the bi-product is the alcohol. The grapes pick up sulfur in the soils and trace amounts can be found in the wine. Often, sulfites are added to prevent discoloration of wine and for added shelf life, often a requirement to be sold in American stores. Then the BATF (Bureau of Alcohol Tobacco and Firearms) requires that all wines sold in stores to be labeled with the words “Contains Sulfites” a requirement that is not on any other label on any other consumable product that also contain sulfites such as dried fruits, nuts and shellfish. Sulfur is a natural element of the periodic table. It’s positives and negatives are the same with most other elements such as Iron and Copper. These elements can help the human body be more resistant to viruses. But as with anything, moderation is the key. Too much of a good thing can be a bad thing. But the stigma that sulfur is bad for you in parts per million quantities as with wine is unnecessary and government overreach.
Many wines undergo malolactic fermentation (MLF). Some wines have malolactic acid because the yeast cells are naturally occurring in the vineyard. Others because malic acid and more yeast are added to the wines. To create a wines with only fruit and floral aromas, the wines are chilled to prevent a secondary fermentation. For a rounder wine with hints of a buttery or creamy texture, the wines undergo MLF.
Lastly, wines are then stabilized and filtered and ready to bottle and drink.
