SRM, EBC and Lovibond: Determining Color in Beer

beer in colors I’m very much for creative license and freedom to experiment in beer, but I think most of us can agree that as consumers, styles designations are incredibly helpful. Happily, there are so many styles and sub-styles of beer! Most of us have a preference for certain ones–knowing the general range of flavors, aromas, carbonation and mouthfeel of the beer you’re ordering is a helpful tool. You wouldn’t feel so confident in the taste of a pilsner if it poured brown, now would you? No way. You’d assume it was someone else’s beer, and send it back. Just like any other food product, different malts have different flavors mostly based on their level of roast or caramelization. 

How do brewers aim for a certain color range in a beer? Luckily there are systems of measurement for the color of wort (pre-beer) and also for individual malts (pre-wort). When writing a recipe, a brewer can find out the expected color outcome and modify the ingredients to achieve whatever is desired. This is particularly important when trying to maintain a strict guideline for a competition–or, perhaps, brew beer in a part of the world that has designated requirements (such as in Köln). Beer color isn’t just a pretty hue–it indicates certain things about the recipe and the brewing process. Every brewery strives for consistent batches of their beer, but large breweries feel additional pressure to maintain a very consistent product–color is always part of the whole package. It’s the first thing you see, after all and yes, you can imbibe with your eyes!

Let’s start with the basics. First, we have the Standard Reference Method or SRM for short. The process is fairly simple: a specific wavelength of light is passed through beer and measured again on the way out. Some light will be absorbed and the remainder is calculated, giving a result that lets us determine a number on a scale. For example, a German Pilsner is between 2 and 5 SRM, while an English Porter is 20-30 SRM. Note to nerds: it’s not a mathematically perfect scale, especially when approaching the darkest wort on the spectrum–but it’s still useful. This method usually uses a spectrophotometer and can detect color wavelengths beyond the human eye’s ability.

The EBC (European Brewing Convention) is a group that governs and develops scientific methodology and standards for the European brewing industry, and the EBC also refers to another way of measuring beer color. It’s a similar method to SRM–but as with most comparative systems from the Americas to Europe, the end result is somewhat differently notated. Luckily there’s a conversion: EBC is about two times SRM–but none of this really matters to us in theory here. Just know that one system or another will get you to an accurate measurement of wort color.

We have multiple ways of determining the color of a finished beer, but what about the recipe development process, stained glass starting with grain? How do we end up with a straw colored light lager and not a brown light lager? Each malt is assigned its own color value–in degrees Lovibond or °L. Named for the brewer who developed the process in 1885, Joseph Williams Lovibond, who was inspired by a church’s stained-glass windows. So beer science, religion…similar. He used a colorimeter or tintometer to determine and reference the color of many things–first beer, then other beverages and food, and now other products as well. It is in fact still a useful tool today. Unfortunately, since it uses color reference points that mimic the somewhat limited human eye’s perception, it’s not as accurate as a spectrophotometer and is primarily only used for individual malt ratings (within the brewing industry that is). For example, a pilsner malt is around 1.2 Lovibond, while a chocolate malt is about 350. Plug all the ingredients into a recipe and one can determine the overall Lovibond rating (and from there, the projected SRM or EBC). Some malts–Crystal, for example, are even known by their number–Crystal 10, Crystal 40, and so forth, a designation of their color that also contributes specific flavors.

It’s true that as a consumer, you don’t always need this information. Perhaps it seems fussy, or overly particular. But I truly think that it’s a useful and beautiful thing to understand the process of recipe development and product measurement of beer. After all, SRM, °L and EBC comprehension are key parts of the creative and manufacturing side of delicious craft beer. And there’s certainly always room for more of that! Cheers to the rainbow of beer.

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