Color coding — matching taste with color

Our experiences and expectations are known to influence our responses. Now researchers at Penn State University in the US say that color can impact the taste of food and could have implications on how food and beverage industries market their products.

The color of a beverage can impact how we think it should taste. For example, yellow is commonly associated with drinks that are sourer, like lemonade, whereas red is associated with drinks that are sweeter, like sports drinks. Based on this, the researchers set out to find how people learn color-taste associations and whether people could be taught new color-taste associations.

Also, the researchers wanted to determine why people enjoy the bitter taste in some foods but not in others. Bitterness usually indicates toxicity, but people still enjoy coffee, chocolate and other bitter foods, but not all bitter compounds.

The research team wanted to find out if there were differences between different bitter compounds, and if people could taste those differences. If there are different types of bitter tastes, it could explain why some people like the bitterness of coffee, but not the bitterness of chocolate.

But first, they needed to test whether they could teach people to associate specific tastes with specific colors. They created solutions that tasted bitter, sweet, sour or savory, and paired each one with a unique color, such as green for sweet or red for bitter. However, they avoided preconceived color-taste pairings, such as yellow for sour or red for sweet, to remove any bias.

The researchers had participants taste the colored liquids over four different sessions, then gave the participants uncolored solutions and asked them to taste and choose a color for each. Remarkably, the participants matched the correct color and taste 59 percent of the time. This was significantly higher than that expected from random chance, which would have been 25 percent. It also surprised the researchers how quickly some participants learned to associate new colors with different tastes.

After showing that they could teach new color-taste associations to their participants, researchers then tested whether people could distinguish between three different bitter tastes — caffeine, quinine, and Tetralone, a hop extract found in beers. The researchers repeated the experiment with a new group of study subjects and assigned unique colors to each bitter chemical, such as yellow for caffeine and green for quinine. However, after four lab visits, participants could not match the colors to their corresponding bitter compounds any better than expected by chance.

Although the study did not get the results they expected, the researchers were still intrigued by how quickly some participants learned new color-taste associations in the first experiment. They now hope to continue to study how people associate taste with color, noting that while some participants were quick learners, others were not.

“Our findings indicate that some people learn color-taste associations well, while others might be more resistant to changes or new color-taste associations. This might have implications in the food industry if a company were to launch a new flavored product with a color. Some consumers might not learn or accept a new color and flavor pairing as well as others,” said one team member.