Harvest. Three grape varieties grow in the Jerez region: Palomino, Pedro Ximénez and Moscatel. Annually harvested in September, 90 percent of the grapes are hand-picked to ensure quality. Grapes that will be used to produce dry wines are then transferred to the wine making plants to be pressed. Those that will produce sweet wines are laid in the sun on grass mats to dry out and sweeten.

Pressing of the Grapes. The grapes are pressed with light pressure that allows the first liquid, known as the mosto de yema, to be extracted. Only this first “must” is used to make Sherry.

Fermentation. The “must” from the pressed grapes is transferred into stainless steel vats for the initial fermentation stage. This first stage is known as the “quick” or “tumultuous” fermentation, during which more than 90 percent of the total sugar contained in the grape is converted into ethyl alcohol and carbon dioxide. In the second stage, a slower fermentation takes place, lasting until the end of November. The result is a dry white wine with 11 to 12.5 percent alcohol content.

Classification. The secret of Sherry’s diverse variety of wines lies in the flor – an oxygen-proof, protective layer of yeast that develops spontaneously on the surface of the wine after the fermentation stages. After the wine has fermented, individual wine makers sample each of the barrels to make an important choice: how the wine will age. The paler, lighter wines are set aside to age biologically bajo flor – under flor – to become Finos or Manzanillas. Other, more full-bodied wines are chosen for oxidative aging without flor and become Olorosos. The wines classified as Finos or Manzanillas are fortified up to 15 percent alcohol content, whereas Olorosos are fortified to 17 percent or higher.

Aging. The fortified wines are then transferred to oak barrels, known as botas, to begin the aging process. In the case of Finos and Manzanillas, the wines are capped by flor, which prevents oxidation and constantly interacts with the wine to give it flavors and aromas. In the case of Olorosos, the higher alcohol content prevents the growth of flor. The wine is then aged according to the solera system, in which the barrels of wine are stacked according to their age in three or four levels. The lowest row of casks, containing the oldest wine, is known as the solera. As wine is removed from the solera, it is replaced with wine from the level above it, known as the primera criadera. The first criadera wine is replaced by the second criadera and so on. Because the wines are blending, there is typically no vintage dating of Sherry. However, it is possible to establish an average age of the wine in each barrel. Though it is frequently aged much longer, the minimum aging for Sherry is three years.