Why Beer Bottles Are Brown or Green?

Ever wondered why most beer bottles are brown or green? It’s not just a marketing decision. These colors serve a crucial purpose: preserving the beer’s freshness and flavor by protecting it from sunlight.

As reported by the Times of India, beer has been stored in glass bottles since the 19th century due to glass’s ability to maintain freshness. However, brewers soon discovered that transparent glass was unsuitable for beer storage. When exposed to sunlight, beer in clear bottles developed an unpleasant smell and lost its flavor.

This issue, known as “lightstruck,” happens when ultraviolet (UV) rays pass through the glass and interact with compounds in the beer, particularly hops. Hops contain isohumulones, which can produce foul-smelling compounds when exposed to UV light.

Why Brown Bottles Are Preferred

Brown bottles are the most effective in protecting beer from UV rays, as they block sunlight and prevent chemical reactions that compromise flavor. By shielding the beer’s delicate compounds, brown glass ensures the drink retains its intended taste. Over time, breweries widely adopted brown bottles to combat light damage. Today, brown remains the most common bottle color in the beer industry.

The Role of Green Bottles

During World War II, breweries faced a shortage of brown glass, leading them to switch to green bottles. Over time, green bottles became associated with premium-quality beer. However, green glass does not offer the same level of UV protection as brown, leaving the beer more susceptible to the lightstruck effect. Despite this drawback, many breweries continue using green bottles for branding and tradition.

The Downsides of Transparent Bottles

Transparent bottles allow consumers to see the beer but provide no UV protection, making the beer vulnerable to light damage. Some manufacturers address this by applying UV-protective coatings to clear bottles, balancing visibility with protection.

The Rise of Cans

Cans have gained popularity as they offer complete UV protection, ensuring the beer remains fresh and unaffected by sunlight. Additionally, cans cool faster and are convenient for outdoor events, making them a practical modern solution.