Tasting blind to strip colour bias out of your judgement

Colour talks before the beer does

Before you smell or sip, your eyes have already told your brain what to expect. Pale gold says crisp and light. Deep amber says caramel. Black says roast, coffee and heavy body. Haze says fruit and softness.

Often those links are right, because colour comes from malt and malt drives much of flavour. Often they are not. A black IPA can be dry and hoppy with little roast. A pale stout, which some breweries make, can carry coffee and chocolate in a golden beer. A dark mild may be lighter in body than a strong pale ale. When the link breaks, your eyes mislead you.

The colour effect is stronger than you think

Colour is one of the most powerful sensory cues there is. In a well known wine experiment in Bordeaux, a white wine dyed red was described by trained students in red wine terms. Beer tasters fall into the same trap. Give a panel the same beer in two colours, with a flavourless colouring added to one. Tasters will often describe the darker one as fuller, sweeter or roastier.

That is why judges and panels who need fair results find ways to hide colour. Our guide on expectation bias covers the wider picture of how labels and cues change perception.

Ways to hide colour

You do not need a lab. Several simple methods work:

• Black or dark tinted glasses. Sensory suppliers sell opaque tasting glasses for exactly this job. Dark blue or black wine glasses work too.
• A red light. Under deep red light, most beers from pale to amber look much the same. Very dark beers can still stand out, so red light works best within a similar range.
• A blindfold. Low tech and effective, though it makes writing notes awkward. Someone else needs to hand you samples and record what you say.
• Small opaque cups. Clean, odourless ceramic cups hide colour and clarity. Avoid plastic, which can add its own smell.

Hide clarity and foam too

Colour is not the only visual cue. Haze suggests a fresh, fruity or yeasty beer. Bright, clear beer suggests a lager or a carefully filtered ale. Foam colour and density give clues too. A dark beige head on a dark beer tells you a lot before you taste.

Black glasses deal with all three at once. If you use red light instead, pour gently so the foam is small and similar between samples. Serve every sample at the same temperature and fill level so nothing else gives the game away.

When blind colour testing is worth it

You do not need to hide colour every time you drink a beer. It earns its place in specific situations:

• Comparing two versions of a recipe where only the malt or the colour changed.
• Training your own palate to describe malt flavour honestly, not from the look of the beer.
• Judging a mixed flight where some tasters have strong opinions about dark beer.
• Checking whether a darker batch of a regular beer actually tastes different, or only looks it.

That last one matters for brewers. Malt colour varies from lot to lot. A batch that comes out a few EBC darker may taste exactly the same, but drinkers who see it beside the usual pour may say otherwise.

Running a colour blind flight at home

Pick three or four beers that cover a range of colours, perhaps a pale lager, an amber ale, a brown ale and a stout. Have someone pour them into dark glasses while you look away, coding each with three digits. Taste and write notes on body, sweetness, roast and bitterness. Guess the colour of each.

Then reveal. Most people find at least one beer was not the colour they expected. Their notes for it change once they see it. Our guide on running a blind tasting at home covers the rest of the set-up, including how to pace it. Keep samples small, have water on the table and plan a way home that does not involve driving.

Your first step

Find two dark glasses or mugs at home. Pour a pale beer into one and a dark beer into the other while someone else watches, so they know which is which. Taste both blind and guess. Swap roles. It takes ten minutes and shows you how much your eyes have been doing the tasting.

Common questions

Does the colour of beer change how it tastes?

Colour does not change the beer itself, but it strongly changes what people expect and report. Darker beers are often described as fuller and roastier even when they are not.

How do you hide the colour of beer in a tasting?

Use black or dark glasses, a deep red light, opaque ceramic cups or a blindfold. Match temperature, fill level and foam so no other cue gives the beer away.

Does red light hide all beer colours?

It evens out the pale to amber range well. Very dark beers can still look different, so black glasses are more reliable across a wide range.