It’s one of those things that goes completely unnoticed because that’s how we’ve always seen it. We’re talking about the red mesh bag for oranges that’s usually sold in supermarkets. It might not have occurred to you that there’s actually a reason why that “bag” has those characteristics, or even that color. But with a global crisis and record fruit prices, nothing is left to chance.

Study. The entire framework behind this distinctive and simple red mesh for fruits is reflected in a study published in the journal i-Perception, a study led by researcher Karl Gegenfurtner from Justus Liebig University in Giessen, Germany. He details how the orange supermarket bag uses what is known as the confetti illusion, or color assimilation, using citrus fruits and the mesh in which they are sold.

Color is important. As they explain in the study, a red or orange plastic mesh surrounding the fruit helps give the impression that the orange’s rind or peel is a much more intense orange color, making it appear juicy and appealing to the consumer. If the fruit is unripe, the colored mesh will also reduce its greenness or enhance its orange color, making it appear less appetizing.

It’s very similar to lemons, for example, because citrus fruits are often placed in yellow mesh bags to enhance their natural color. In fact, Gegenfurtner says that if they were placed in red bags, they would look orange and not traditionally very appealing. What’s interesting is that this is all an optical illusion.

Confetti illusion. This phenomenon, also described as color assimilation, occurs when objects take on the color of something above them. In a science experiment conducted in 2021, colored lines were placed on a white circle. What happened? The circle took on the color placed in the foreground.

This effect is actually an optical illusion in which color perception is strongly influenced by the surrounding context. In this case, a neutral colored ball is placed inside a grid of lines of different colors. When lines of a certain color are in the foreground, the color of the ball appears to blend with the lines.

Gegenfurtner visual test

Experiment. As Gegenfurtner puts it, he wanted to prove the illusion true in the field. Like? The researcher describes how he buys oranges for juice every Saturday at his favorite fruit shop, Helga’s, at the local market. “One day, as expected in the German summer, I didn’t have any nice, ripe oranges on hand. Then I walked past a supermarket and it seemed like there were plenty of ripe oranges, so of course I bought a bunch of them, packed them conveniently in an orange net and took them with me,” he elaborates.

When the man got home, he removed the oranges from the net and the “miracle” happened: “Every single orange that was a beautiful color inside the net had turned into an unpleasant shade of green!” He later documented the claim with photographic evidence, showing some misleading oranges (pictured above).

Solution. As stated in the published study, the researcher concluded that color assimilation alone has a very strong effect on the appearance of the color, for example, turning a greenish-looking orange into a beautiful orange. The study reminds us that the confetti illusion is based on the principle that our brain is programmed to process peripheral vision and color perception.

In other words, our brain aims to provide us with a fluid and uninterrupted experience that can be understood in the most efficient way possible, and the visual part accompanies this principle and gives it integrity. In the case at hand, when there is a red network on an orange network, the brain combines colors to simplify it.

This is the market, my friend. Of course, this should not be new to the business world. “It goes without saying that fruit vendors have long since realized this. If we look around typical supermarkets, it is easy to see that fruits and vegetables (e.g. lemons, onions, zucchini and even potatoes) are often packaged in nets in the color of perfect specimens,” the study concludes.

Picture | Morlawmina, Gegenfurtner/i-Perception/2024

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