What is the role of flor in Sherry production?

Flor plays a crucial role in the production of Sherry by acting as a natural protective barrier that prevents the wine from being exposed to oxygen. This layer of yeast cells forms on the surface of the wine as it ages in the barrels, creating an environment that allows for unique fermentation processes. By covering the wine, flor allows it to develop distinctive flavors and aromas while simultaneously inhibiting oxidation, which would alter the character of the wine unfavorably.

Without flor, the wine would be vulnerable to oxidation, leading to a different style of Sherry that lacks the rich, complex flavors associated with biologically aged Sherry. This process is vital for styles such as Fino and Manzanilla, where the influence of flor is essential for achieving their signature profiles.