There's no clear answer as to why lime wedges have become de rigueur for Coronas in the United States, but a number of theories exist:
- Unlike almost every other beer in the U.S. market, Corona is bottled in clear glass rather than brown or green. Those who know beer recognize that light is an enemy of the brew, turning beverages exposed to it "skunky." The lime, therefore, masks the altered taste resultant from Coronas' having been exposed to light by virtue of their packaging.
- Corona is a mild-tasting beverage, with the inserted lime adding its only discernable note of flavor.
- The provision of a lime dates to the days when metal caps sometimes left circlets of rust on the rims of beer bottles. The fruit slice was used to wipe away rust stains the brew's drinker would otherwise have been putting his lips to.
- Lime (or lemon) is said to work to keep flies away. In an expansion of that theory, prior to the lime slice, fly spray used to combat the flying hordes adversely affected the taste of the beer.
- Some bright spark who works for the brewery came up with the idea of festooning bottles of Corona with wedges of lime, both in an effort to create a more visually enticing image and to provide what might otherwise be regarded as a somewhat uninspired beer with a hint of cachet, and possibly even an intriguing (if unstated) backstory. People like both ritual and mystery, after all, and the lime provides both.
- On a bet with a colleague about whether a single person could start a nationwide trend, a bartender came up with the notion of shoving limes into Coronas.
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Content from snopes.com