Ever wondered why lemons are often sold in those yellow net bags? Well, it’s a sneaky trick used by food producers and supermarkets to fool your senses and (hopefully) make you buy more fruit.
The same is true of oranges - which are frequently sold in red mesh bags. The packaging of oranges and lemons in these particular ways makes use of a bit of visual trickery known as the confetti illusion.
A red or orange plastic net around oranges helps to give the impression that the orange peel is a richer orange colour, thereby making it look juicy and appealing to consumers. If the fruit is unripe, the coloured net will also downplay its greenness and boost its orangeness, making it look ripe and more appetizing.
Similarly, lemons are often put in yellow net bags to enhance their natural colour. If they were put in red bags, they’d look orangey and not as conventionally appealing.
The principle is based on the confetti illusion, a visual phenomenon where the perception of colours is strongly influenced by its surrounding context. In this optical illusion, a neutrally coloured ball is placed within a grid of differently coloured lines. When the lines of a particular colour are in the foreground, the ball's colour appears to blend with that of the lines.
In a new study, psychologist Karl R. Gegenfurtner from Giessen University in Germany details how supermarkets' coloured bags utilize the confetti illusion. His paper explains that the confetti illusion is based on the principle that our brains are programmed to process peripheral vision and colour perception.
In essence, our brains aim to provide us with a smooth, seamless experience that can be understood as effectively as possible. Likewise, our visual system is wired to perceive uniformity and smooth transitions. When the yellow netting is placed over a lemon, our brains merge adjacent colours to simplify what we see.
Whether or not this trick of deception actually increases the sales of lemons and oranges is still a moot point - and OGN would like to encourage researchers to take on the task.