If you’re a brewmaster making beer for the enjoyment of others, the ingredients and process you use are paramount. Quality control is paramount to beer drinkers who desire consistency with every pint. Regardless if you like Budweiser for example, no one debates that they have quality control mastered as you always know how your beer will taste. One of the key factors to this consistency is the colour of their bottles.
The two biggest issues to affect your beer once bottled are light and temperature. Either of these can significantly affect the flavour of your beer, especially the former. This is why you see beer nerds cringe when they watch a beer commercial that shows open beer in the sun; two seconds of direct sunlight will “burn” or “lightstruck” the beer and make it taste off. This is because light, especially ultra-violet (U.V.) light, causes an instant reaction, changing the iso-α-acid to 3-methylbut-2-ene-1-thiol. If this sounds nasty, it is. The “thiol” change is means sulphur, and even the smallest amount of sulphur, like one part per billion, will make your beer taste skunky. And this is simply why beer bottles are typically brown; they’re created specifically as a U.V. filter, to protect your beer. Typical brown beer bottles don’t fully protect your beer so you should still try to shade even a U.V. bottle. Knowing what I’ve just explained, I’d suggest that any brewery that provides you clear bottles is missing a huge step in ensuring the quality of their beer, and why you may notice inconsistency of taste. You’ll also notice that these type of bottles typically come from the hottest areas that could use it the most!
I like the trend of going the other direction. For example Rogue Brewing now offers their XS series in ceramic bottles, which are completely opaque, and Lighthouse Brewing’s Belgian Black has a powder coat of black on top of the amber glass which Dean McLeod their brewmaster informed me it makes the bottle “…almost as lightproof as an aluminum can”. These are breweries that understand, and are committed to quality U.V. protection.
I have a hope that some day pubs and restaurants will start to understand and respect this. I envision a future where you’ll be on a patio and enjoying the sun, and you’ll know you’re at a quality establishment if they bring you your beer, with some type of shade covering device. I’ll often open a menu 90 degrees and use it to shade my beer, and if asked, I use the opportunity to explain it politely to my server.
For more technical details, check out this Australian Brew News article, and remember, friends don’t let friends drink beer from clear, non-U.V. protected beer bottles.