Beer is predominantly sold in green or brown bottles because these colors protect the beer from light exposure, which can negatively affect its taste and quality. Here’s why these colors are preferred:
1. Protection from UV Light
- UV (ultraviolet) light can break down certain compounds in beer, especially hops, causing a chemical reaction that produces a skunky or “lightstruck” aroma and taste.
- Brown glass is the most effective at blocking UV light, providing excellent protection.
- Green glass offers some protection but is less effective than brown. It became popular primarily for historical and marketing reasons.
2. Historical and Marketing Reasons
- Brown Bottles: In the early 20th century, brown glass became the standard because it was widely available and highly effective at protecting beer.
- Green Bottles: During World War II, brown glass shortages led some European brewers to use green glass instead. Over time, green bottles became associated with premium or imported beers due to their use by high-quality European breweries, making them a marketing choice despite offering less UV protection.
3. Cost and Availability
- Brown and green glass are also easy to produce and widely available, making them cost-effective choices for breweries.
4. Aesthetic and Branding
- Green bottles are sometimes chosen for branding purposes, as they can create a distinctive and recognizable look. They are often associated with specific beer styles or heritage brands.
For beers sold in clear bottles, brewers often use hop extracts that are chemically modified to resist light damage, as clear glass provides no protection against UV rays.