COLOR

Creating the perfect beer is truly a craft. Both beer connoisseurs and casual drinkers alike often know exactly what they’re looking for in a beer and, just as importantly, what they’re not looking for. As such, breweries must take great care in creating beers that not only taste delicious but are appealing to the eye.

Each ingredient added to a beer will change its color slightly. As grains are by far the largest percentage, it is understood that they have the most impact on your final beer’s color. Most grains in their unmalted and unroasted form would impart just a pale yellow color to the beer. As grains are roasted at higher temperatures for longer times, the color they add darkens considerably.

There are a few different methods that are used to measure the color of beer such as, SRM, EBC, Lovibond and MCU.

For decades, beer was compared to colored glass standards to determine the Lovibond color, and we still use the term “Degrees Lovibond” extensively today to describe the color of grains.

Today there are a few different methods that are used to measure the color of beer such as, the Standard Reference Method (SRM) color system, the European Brewing Convention (EBC), Malt Color Units (MCU), and still in use, the Lovibond Scale.

Beer Color

Color

An important sensory attribute of a beer is its color, and is the first characteristic observed by the consumer. The color of the beer usually provides an indication of what to expect from the taste. For example when ordering a stout, dark beer that typically contains some roasted malts, the expectation is that the taste will have flavors of chocolate, coffee, and/or darker notes.
A wheat or weiss beer that has a medium-gold gold color and is made with wheat or barley should provide some bready flavors, while a malt-driven Irish red beer should offer some notes of rounding fruit or nuttiness.
A light-colored beer such as a Pilsner, will usually have brighter characteristics with hints of, citrus, crispness, tropical fruit notes, or pepperiness flavors.

Similar to aromas, the color spectrum can vary wildly, appearing almost translucent, pale golden, amber, ruby, garnet, and brown, all the way to dark black. Several measurement scales have been developed to provide descriptions of the various colors. Totally different units are used in England and Europe as opposed to the U.S.. This is because of the different analytical procedures that are used for measurement.

Factors Affecting Beer Color

Grain is by far the strongest coloring agent in beer, and grains are colored by melanin, a rust-red pigment that drives the color of beer. But what else can influence the color coming from the malts?

Grain Roasting: The more roasted the malt is, the darker the beer will become. Even within specific classes of grains such as: Chocolate Malts or 2-Row, there will be a slight variation of grain colors.

Mashing & pH Levels: Mashes with higher pH levels in the water are linked to having darker beers. While this is more common during the mashing phase, it can impact the beer at all stages of brewing.

Boil Length & Cooling: Longer boil times allows for extracting more of the color in the mash. It also caramelizes the mash, making it appear darker. The intensity of the temperature difference in the cooling phase will significantly affect the beer color and clarity.

Yeast Strain: The yeast strain used in brewing a beer can also have impact on the color.

Filtering: If the beer is not filtered, any suspended particles will deflect the light more, causing it to appear to have have a darker color.

Joseph Williams Lovibond

Joseph Williams Lovibond, born 17 November 1833 at Long Sutton, Somerset, was the third son of brewer John Locke Lovibond. At the age of 13, he entered the merchant navy, and in his later teens, he dug for gold in California for three years. Soon after his return to London, he assumed control of the business, adding a brewery in Salisbury.

In 1880, Joseph Williams Lovibond is looking for a method to give beer a consistent colour for his brewery. The light that colourfully shines through a church window in Salisbury gives him a groundbreaking idea: he wants to use glass to achieve consistent, constant colour standards. Lovibond develops the first worldwide comparator in the kitchen of his home: a disused sugar bowl with improvised slits is the prototype. Exactly two beer glasses fit into it, which can be easily compared. At the same time he develops his own color scale which makes it possible to measure each colour accurately. The basis for this are glasses in the three basic colours red, green and yellow. 200 glasses with colour variations of each basic color allow 9 million combinations and thus the option to adjust every conceivable colour.

Lovibond introduces the Tintometer, the first colorimeter, an instrument used to measure the color of transparent liquids as matched with combinations from three graduated sets of 20 each yellow, red, and blue color filters. ln 1885, he founded the Tintometer Ltd. Company in Salisbury to manufacture his tintometer. Today the company still produces various types of color-measuring instruments.

Lovibond's Published Studies

In connection with these activities, Lovibond concerned himself with scientific aspects of color, producing three publications: Measurement of light and colour sensations (1893), An introduction to the study of colour phenomena ( 1905), and Light and colour theories and their relation to light and colour standardization (1921). Near the end of his life, Lovibond conducted investigations into color camouflage for the British War Office.

The first book describes the Tintometer and its uses. The test liquid is placed in a glass cuvette and inserted into the tintometer. A series of glass fillers can be placed in slots next to it. By visual comparison, looking through the ocular, the color of the test liquid is matched in color appearance against combinations of appropriately selected filters, a task requiring some practical experience. The measured color or the liquid was identified with filter and filter strength numbers

Lovibond's Tintometer was (and in modified form is) widely used for specifying the color of liquids of many kinds. Using a modern instrument, Mark Fairchild produced a modern and growing listing of widely varying yellow, cyan, and magenta Tintometer values of many beers of the world.

Color Scales

Lovibond (°L)

The system used to characterize beer color has its origins in the late 1800’s. The original lovibond system was created by J.W. Lovibond in 1883, and used colored slides that were compared to the beer color to determine approximate value. For decades, beer was compared to colored glass standards to determine the Lovibond color, and we still use the term “Degrees Lovibond” extensively today to describe the color of grains.

Over time, limitations of the Lovibond were recognized, not the least of which was that it depended upon a person’s vision - which naturally has variations in color perception from person to person. By the mid-20′th century, light spectrophotometer technology was developed.

The Lovibond scale has mostly been replaced by the SRM and EBC methods in their respective countries for measuring beer color. However, it is still commonly used on packaging and online stores for reporting the color of malt and other brewing ingredients.

Standard Reference Method (SRM)

The most common value used in the U.S. to measure beer’s color is the Standard Reference Method, or SRM. It was developed by the American Society of Brewing Chemists (ASBC) in 1950 as the scientific standard for identifying beer color. absorption.

The SRM scale typically goes from 1 to 40+ and covers colors from pale straw to straight black, though some beers can measure higher than 40. If the SRM color is higher 40, it will still be classified as black or opaque. Imperial stout is an excellent example of a 40+ beer. The lower the SRM, the lighter the beer’s color, and the higher the SRM, the darker the beer’s color.

To measure the SRM, a photometer or spectrophotometer is used . Blue light is passed through 1 centimeter of brewed beer: the amount of light lost is then multiplied by 12.7, the resulting number is your SRM. The more light lost through the centimeter of beer, the higher the SRM and the darker the color of the beer.

European Brewing Convention (EBC)

European breweries use the EBC (European Brewing Convention) chart for quantitatively describing beer color. The procedure is very similar to determining the SRM value.

The EBC system of color measurement is similar to that of the SRM chart. EBC measurements are taken at 430 nm in a 1 cm cell where the unit of color is 25 times the dilution factor, as opposed to 12.7 times the dilution factor used in the SRM chart. Therefore EBC is approximately twice SRM and this applies at any color value. Just as in the SRM chart ,the higher the EBC value the darker the beer.

The EBC method is quantitative and involves measuring the beer sample color in a cuvette that is placed in a spectrophotometer at a wavelength of 430 nm. This particular wavelength was selected so that the final measured color was in agreement with Lovibond references. The EBC color system is used primarily in Europe

Malt Color Units (MCU)

Malt Color Units (MCU) is an easy way for brewers to calculate the approximate color expected in a given recipe with multiple grains and adjuncts. This is especially useful for recipes that you are making for the first time.

In order to calculate MCU of a recipe, the calculation is:
MCU = ((Grain Weight Pounds * Grain Lovibond) / Volume Gallons)

The MCU value provides a fair color estimate for beers that are very pale in color or less than 10.5 SRM. At the low end of the SRM spectrum, MCU and SRM values close enough to use the different values interchangeably. However, because light absorbance is logarithmic and not linear, the Morey equation is needed for a better estimate of color for most beers.

Measurement Instrumentation

Instrumental color measurement is more straightforward than visual methods, eliminates subjectivity, is more precise, takes less time and overall is much simpler to perform. There are basically three types of color measurement instruments used for cereal and cereal product color measurement. These are the monochromatic colorimeter, the tristimulus colorimeter and the colorimetric spectrophotometer.

Comparators

Another method of assessing color uses standard, calibrated, tinted glass discs. These are directly compared with a beer sample. Disc and sample share the same background illumination in a purpose-designed comparator. The two main instruments used to compare colors are the Lovibond Comparator, and Hellige Neo-Comparator.

A beer sample is place in a cuvette. The cuvette is chosen to match one of the color disks. This means that a sample can be made "lighter" to view by using a thin cuvette. There are various colour disks. Each small circle contains colored glass that matches a certain colour and cuvette size. The disc is placed in the machine. The cuvette is placed into the slot on the machine. Both are looked at through the viewfinder. The disc is rotated until a disc matches the sample. The color is read from the disc comparator scale.

In all color determinations it is important to de-gas and filter beer samples. Haze, turbidity and gas bubbles will affect measurements.

Monochromatic Colorimeter

The monochromatic colorimeter does not measure color per se. It only measures the amount of light reflected in relative units in a narrow area of the red, green, blue or yellow region of color. Because of this, a monochromatic colorimeter is basically colorblind and sees only all red, or all green, or all blue, or all yellow. Thus it can easily give erroneous results. For example, to measure the “browness” of grain flakes the green filter may be used to measure lightness to darkness.

If there were two different batches of grain where one was a light brown and the other was a darker brown but with a green cast, the instrument could indicate that they were the same color even though visually they would look different. A benefit of the monochromatic colorimeter is that it can view a large area (6” diameter) and obtain a good optical average of relatively large coarse samples such as corn, oat, or wheat flakes.

Tristimulus Colorimeter

Methods using multiple colors, called tristimulus, can be used to measure beer in a way that matches more closely what the eye sees, but these are rarely used in brewing.

The tristimulus colorimeter can view large areas of sample (6” diameter) and obtain a good optical average of relatively large samples, but has the added benefit that it measures true color and correlates to what the eye sees. It actually simulates the eye/brain sensitivity to color by simultaneously using specialized glass color filters and light detectors. The human eye can detect up to 10 million different shades of color and the tristimulus colorimeter can quantify all of them.

Tristimulus values may be obtained from measurements made on a tristimulus colorimeter that visually matches a color under standardized conditions against the three primary colors—red, green, and blue; the three results are expressed as X, Y, and Z, respectively. These must then be normalised to equivalent CIE values and should be properly designated as R, G and B instead of X, Y and Z.

Colorimetric Spectrophotometer

Like the tristimulus colorimeter, the colorimetric spectrophotometer measures true color. However it uses a somewhat different measurement principal. It measures the entire visible spectrum of light (rainbow) being reflected from a sample and then using mathematical tables representing the human eye color sensitivity and mathematical tables representing the color output of different light sources, calculates the result.

This type of instrument is even more precise than the tristimulus colorimeter and at the same time is normally lower in cost than either the monochromatic colorimeter or the tristimulus colorimeter. It does not measure as large an area as the tristimulus colorimeter and thus is best for measuring samples like rice, flour, wheat, corn, barley, starch, and less coarse breakfast cereals. Some colorimetric spectrophotometers also have the ability to measure transmitted color so they are suitable for measuring samples like corn syrup and grain alcohol.

Our Gallery

Contact Info