Beer Geek 101 - Degrees Lovibond, Measuring the Color of Beer

"Degrees Lovibond" or "°L" scale is a measure of the colour of a substance, usually beer, whiskey, or sugar solutions. The Standard Reference Method (SRM) and EBC method have largely replaced it, with the SRM giving results approximately equal to the °L. The determination of the degrees lovibond takes place by comparing the color of the substance to a series of amber to brown glass slides, usually by a colorimeter. The scale was devised by Joseph Williams Lovibond.^[1]
The Standard Reference Method or SRM ^[2] is a system modern brewers use to measure colour intensity, roughly darkness (but see Tristimululs Color below), of a beer or wort. The method involves the use of a spectrophotometer or photometer to measure the attenuation of light of a particular wavelength, 430 nanometers, as it passes through a sample contained in a cuvette located in the light path of the instrument.

Colour based on Standard Reference Method (SRM)

SRM/Lovibond	Example	Beer color	EBC
2	Pale lager		4
3	German Pilsener		6
4	Pilsner Urquell		8
6			12
8	Weissbier		16
10	Bass pale ale		20
13			26
17	Dark lager		33
20			39
24			47
29	Porter		57
35	Stout		69
40			79
70	Imperial stout		138

      O.k. so this is not so practical of a scale, I have yet to attend a casual brewers meeting in which this was a hot topic, usually you hear color talked about in a much more general way. But you will see the SRM or L scale at the beginning of some recipes and it is worth knowing what you are going to get yourself into before you start brewing, Any questions or comments on describing the color of your beer, please contact us at Pearl City SOBs, or leave a comment below.