How to Apply Your Colour Analysis in Quality Control of Coffee

Coffee can be the best way to start your morning, but before it gets to your favorite mug, a roaster ensures it has the right colour for its roast. Colour can be complex and challenging to thoroughly examine with the human eye. With special measuring tools, like a spectrophotometer, roasters can meet colour standards in the coffee industry.

Colour Standards in Coffee Assessment

Coffee beans start green, and roasting darkens the bean and changes the flavor. This roasting process is why there are light, medium and dark roasts. Bean colour is a significant indicator for the kind of roast and the flavor the coffee will have.

When it comes to deciding on the right colour for a coffee bean, you need to consider how we see colour. Colour comes from the amount of light a substance absorbs or reflects, often called optical properties. The colour of the light and where a person stands can affect how they perceive colour. While the human eye can perceive a series of wavelengths to register colour, it can’t see all of them, which may affect colour quality.

Colour consists of three properties — hue, saturation and brightness. To get accurate measurements of these quantities, coffee roasters can use colour measuring instruments. These tools, like spectrophotometers, remove human subjectivity from colour and make coffee roasts more definable.

Apply Colour Analysis to Coffee

Using colour measuring instruments can make it simple to apply colour analyses to coffee beans. Over time, coffee bean analysis has allowed us to create ideal measurements for varying roasts. We know what the hue, saturation and brightness should be for light, medium and dark roasts, and these act as controls for measurement.

A roaster will measure a batch of coffee beans and compare the colour to these controls based on the roast they’re trying to achieve. If the beans are too dark or too light, they can reduce or increase roasting time. Even a roast that happens too quickly can affect a coffee bean’s quality and change its determiner from light to medium.

Spectrometers can give you a baseline for roasting practices so coffee beans will always offer the proper darkness or lightness for their roast.

Best Brewing Practices

While meeting colour standards in coffee quality can help a roaster achieve the right roast level, brewing practices can also affect the taste. There are many coffee brewing devices, from standard coffee makers to french press and pour-over instruments. These methods all have slightly different approaches for achieving the best brew.

You should consider three factors in your roasting process — the size of the grain, the water-to-coffee ratio and water purity. While standard coffee makers require less water and work with various grain sizes, pour-over and french presses require medium to large grains with a different water-to-coffee ratio.

Analyze Coffee Colours With HunterLab

HunterLab specializes in spectrophotometers for quantifiable colour measurement. Contact our team today to learn more about how we support the best roasting practices.