Beer Color Laboratories
There is a lot more to the Color of Beer than you Think!
Welcome to a Website Dedicated to "Beer Color"
This website will always be a work in progress!
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Recommended Instructions for Use
For proper and accurate use please follow instructions. Beer Color Reference is calibrated at 1 cm about ½ inch. Best results are achieved when examining ½ inch of beer in a plastic judging cup with the cup and this guide placed on the same background. Beer color determination is best done in the presence of broad spectrum lighting. Greater beer depth and its SRM can be estimated by placing this transparency over a white background and examining the elevated beer sample. Most Accurate - Fill or leave a beer sample of ½ in a clear container such as a 6 oz. clear plastic judging cup. Place the container and the guide on the same background. look down and thought the ½ depth sample and move the guide or sample until a best match representative color sample can be seen and determined.
Beer color evaluation can be difficult. Various methods have been used to quantify the color of beer. The son of a brewery owner in Greenwich, London, Joseph W. Lovibond researched beer color and in 1885 formed the Tintometer Limited to standardize these colors using a comparator. His Tintometer would compare any samples to his permanent standards side by side until a best match was found. The Lovibond scale ºL is in common use with beer, grain malt, and wort color evaluations. Today the Tintometer comparator is used in many applications with hundreds of standard samples, usually glass, available. The standards used here are base on increasing concentrations of chemicals such as potassium iodine and dichromate. The problem with this type of measurement is that all beer is not the same color varying in its apparent lightness and darkness.
Over fifty years ago another method for standardizing beer color was propose and adopted. The American Society of Brewing Chemists developed a Standard Reference Method, SRM, to grade beer color. Basically a 1 sample is exposed to a single Ultra-Blue - Powder Blue light of 430 nm and by its absorption the SRM value is determined. The color of light works well with yellow-brown liquids but again this type of measurement has some problems. Many beers of different perceived colors will have the same SRM value and can for example appear as amber or red-yellow and have the same SRM. Not all beers have the same colors and while these methods suggest a difference in light or darkness they do not suggest its true color
There are many analyzers that can measure Beercolor by actually sampling separate and individual wavelengths of light and producing a true color determination by tristimulus colorimetric methods. Many are used in large breweries where color consistency is extremely important. These devices are quite expensive and are not useful for small and multiple samples. Many are very large and not portable. There are smaller devices that can determine color used in manufacturing, industry and interior design but then again they dont lend themselves to usefulness in beer sampling. Using a comparator with a computer can be done but is not that convenient for calibration of beer samples. Your monitor, printer and lighting must be precisely calibrated which is very important for reproduction of a reference.
When examining a beer sample the viewer is using their experience and the environment to suggest color and depth. The sample is composed of many compounds that add to or give the beer its color different combination of these compounds can provide the differences in the color but also different color combinations can have the same apparent color as they form metamers. This lends to a different problem as each individual perceives these colors, their depth and hues and combinations differently. So even if you are not colorblind you may perceive the color, SRM or Lovibond, differently, than the judge or examiner under the same conditions sitting next to you.
Many factors of the environment will affect color judging or measurement of a specific beer. Each evaluator can actually see these colors differently. Under most conditions and with most users these guides will place a beer within a couple of degrees of Lovibond and can yield information on style guideline fit and brewing/recipe recommendations. However, I think you should keep in mind that there are many possible sources of error in this kind of evaluation. Enjoy the beer. Beer Color Laboratories.
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