How long does it take for "skunky" reduction to occur when exposed to light?

Skunky reduction, often referred to as lightstruck flavor, occurs when beer is exposed to ultraviolet (UV) light, especially in beer packaged in clear or green bottles. The compounds in beer, particularly hop-derived iso-alpha acids, react with UV light, leading to the formation of substances like 3-MBT (3-Mercapto-3-methylbutyl acetate), which produces a characteristic "skunky" aroma.

Research indicates that this undesirable alteration can start to take effect very quickly, often within just a minute of exposure to direct light. This is why the answer indicating a time frame of one minute is accurate. Keeping beer away from light when storing and serving is crucial to preserving its flavor integrity.