For Mr. I, tomato juice is black. He knows it’s not really black, but he can’t see it any other way, even in his mind. In An Anthropologist on Mars, neurologist Oliver Sacks tells the story of Mr. I, a painter who developed cerebral achromatopsia, or the inability to perceive color, following a car crash. For Mr. 1, Black tomatoes don’t taste right, so he closes his eyes and imagines biting into a ripe, red tomato, trying to erase the visual variable. “But this did not help very much,” Sacks writes, “for the mental image of a tomato was as black as its appearance.”
And tomatoes weren’t the only trouble; any foods that didn’t match the colors he remembered from before the accident were unappetizing and no matter how he tried to visualize that he was eating an orange orange or a yellow banana, his brain refused to believe him. In the end, he decided that he would eat only foods that matched his memories, leaving him with a black and white diet that would include plain but not strawberry yogurt, black but not green olives.
Most of us naturally understand that color impacts our perception of foods. After all, we constantly evaluate foods based on their hue, from checking if the meat is still red to guessing an avocado is ripe when its skin becomes dark green. But color does more than alert us to physical or chemical changes in food; it also deeply impacts how we taste them and, sometimes, even if we taste them. Color is so powerful that it can override what our other senses are telling us to be true, causing us to taste sweetness that isn’t really there, experience flavors that aren’t present, and accept or reject foods simply based on their shade. By understanding the profound effect of color on gustatory experiences, food manufacturers can gain richer insight into consumer expectations and the importance of creating and monitoring the color of edible products.
The Psychological Effects of Food Color
Does food color influence taste and flavor perception in humans? The short answer is yes, as several factors impact a person’s psychological and sensory experience with food, including texture, temperature and appearance. Studies have shown that color can influence the eating experience in multiple ways.
When eating or drinking, most people take in visual information first. They observe how the food looks in contrast to the surrounding plate or container and draw on years of experiences with similar foods before taking a bite — making assumptions about what the food will taste like and how satisfying it will be. Whether consciously or unconsciously, color impacts the following psychological aspects of the eating experience:
- Flavor: People make assumptions about what their food will taste like using color. They may believe that a bright red apple will taste sweet, for example. If the real flavor of the food fails to meet expectations, the brain may not perceive the difference, replacing existing tastes with expected flavors or elevating tastes that are milder than anticipated.
- Fullness: People may eat more or less of a food depending on its color and presentation. White foods such as popcorn may encourage mindless snacking, for example. Studies also indicate that plate color influences how much people choose to eat. However, additional research is needed to determine whether the color itself or the contrast between the plate and the food causes this effect.
- Enjoyment: People often associate brighter-colored foods with better nutrition and flavor. This holds true for fresh produce and candy. If a person finds the color of a food appealing, their overall enjoyment may be enhanced regardless of actual flavor or nutritional content.
- Food choice: People naturally gravitate toward foods with appealing colors and avoid foods with unappealing or worrisome colors. Foods with colors that indicate spoilage or poor quality are unlikely to sway customers at the supermarket.
Flavor Identity: How Each Color Affects Taste
Different foods feature many different colors. As a result, we form connections between specific colors and corresponding flavors. Depending on culture and past experiences, you might assume that a red drink is cherry, strawberry, cranberry or even tomato-flavored — but you probably wouldn’t assume it tastes like peach. Due to the assumptions we make about flavor, color and taste perception are closely linked.
Different colors affect taste in various ways. Foods with a bright red color can increase perceptions of sweetness and decrease perceptions of bitterness, which is why some manufacturers apply red coloring to the outside of fresh apples and tomatoes. In contrast, foods with unexpected blue coloring could cause some people to lose their appetite due to the color’s rarity in nature.
Off-Coloring in Food
Off-coloring refers to a color that conflicts with the consumer’s beliefs about what a given food should look like. Off-coloring can be natural, such as the green, black or white associated with mold. However, off-coloring can also be artificial. Customers avoid off-colored foods, so it’s important to carefully choose artificial coloring to avoid the negative effects of color on flavor perception.
The Impact of Color on Flavor and Food Identification
In 1980, a study was published in the Journal of Food Science that remains one of the most significant pieces of research on the effect color has on how we perceive, identify, and, ultimately, experience foods.2 Using a series of experiments a designed to examine the relationship between color, flavor, and food identification, the researchers made some remarkable discoveries regarding our perception of foods:
- Experiment 1: Subjects were asked to identify the flavor of four different fruit-flavored drinks while wearing red eye-googles in a room with red fluorescent lighting, making it impossible to distinguish the color of the drink. While 70% of participants were able to correctly identify the grape-flavored drink, only 20% of participants were able to identify the orange-flavored drink, even though 100% of them identified all of the beverages correctly under normal lighting conditions.
- Experiment 2: Participants were asked to describe the flavors of beverages that had their typical color additives removed and replaced by atypical colors. The researchers found that “inappropriate coloring … induced flavor responses that are normally associated with that color.” In other words, the participants perceived an orange-colored, cherry-flavored drink as tasting like orange, not cherry.
- Experiment 3: Research subjects were asked to identify the acceptability of flavor of 12 cake samples consisting of four color levels and three flavor levels under either white fluorescent lighting or color-masking red lighting. Both the acceptability of flavor and perceived flavor intensity were significantly affected by color level; the brighter the cake was, the more intense it was reported to be. These effects were not observed in participants who tasted the cakes under color masking conditions.
The findings offer profound insight into the vital role color plays in shaping our perception of foods, often overriding other sensory faculties and charting an experiential course at odds with material reality. As the authors note:[These experiments] emphasize the fact that a product’s color affects observers’ judgments of other qualitative attributes of that product. While flavor level could be adjusted to offset reduced color levels in some circumstances, this was not the case throughout the color range, and that a certain level of color was very important to consumers.
Subsequent studies have confirmed these findings in a variety of contexts, from investigations into how wine color affects sensory perception to cultural differences in corn color perception and acceptability. Some research goes even further to investigate the impact of ambient color, revealing that food packaging can significantly affect our experiences of taste due to the contrast it creates (or doesn’t create) with the food it contains.
The Neurobiology of Food Experiences
So why does this happen? As Tom Vanderbilt asks in Nautilus, “Is it that participants simply cannot fully discern what that flavor is, and so rely on visual cues to help inform their decision? Or does color actually change the experience of taste?”3 Charles Spence, head of the Crossmodal Research Laboratory at Oxford University, says that the answers can be found in our neurological activity. Over 50% of our cerebral cortex is devoted to visual processing while only 1-2% is involved in taste. As such, our brains rely heavily on visual information, particularly color, to anticipate and organize our experiences of foods. However, color information doesn’t simply act on our brains, our brains act on color information, drawing on years of conditioning to predict future experiences.
Spence says that while experts used to believe that, “All this information comes from outside through our eyes, ears, and tongue and works its way up through the cortical hierarchy, at each stage being condensed, it turns out that there are more pathways going from the inside out.” In other words, if we encounter a ripe red tomato, our brains have a back catalogue of previous experiences with ripe red tomatoes that sets our expectations well before we taste the fruit and this information becomes part of our eating experience. If the tomato doesn’t actually have the sweetness we expect, our brains can compensate for that lack by shutting out unwanted information and, on an unconscious level, ascribing a sweetness that isn’t truly present because we innately want to create a cohesive narrative of our gustatory experiences.
Similarly, if we are presented with an orange-colored cherry-flavored beverage, our brain is invested in experiencing it as orange, discounting the cherry flavor information and replacing it with the information that is consistent with our expectations. As Dunovan, Tremel, and Wheeler write in a 2014 study published in Neuropsychologia:
Anticipating a forthcoming sensory experience facilitates perception for expected stimuli but also hinders perception for less likely alternatives. Recent neuroimaging studies suggest that expectation biases arise from feature-level predictions that enhance early sensory representations and facilitate evidence accumulation for contextually probable stimuli while suppressing alternatives.
This may explain the failure of products such as Crystal Pepsi, Miller’s clear beer, and Burger King’s black burgers in the U.S. market; the color of the products did not line up with expectations.4 Developing food products that meet consumer expectations of taste, then, requires developing recipes that take into account the pre-existing database of expectations that each person carries with them and offering items that fall into an ongoing narrative of gustatory experiences.
Using Color Measurement to Enhance Perception of Foods
Food manufacturers often spend considerable resources evaluating the taste and appearance of foods to determine if their products will be well-received within the marketplace. Once in production, it is imperative that the products manufactured fall within acceptable color standards to optimize success. Spectrophotometric evaluation of foods and food packaging throughout the manufacturing process ensures food colors meet expectations and enhance consumer perception.
Today’s advanced spectrophotometers offer a range of optical geometries that make them ideally suited for measuring the color of all forms of edible products, from smooth and glossy solids to textured powders to clear liquids, using portable, benchtop, and in-process instrumentation. By automatically alerting you to undesirable color shifts, you can quickly quarantine out of spec products and take corrective action to address the problem, help you realize immediate cost savings, and preserve your brand reputation.
HunterLab offers a comprehensive range of spectrophotometers and sophisticated software packages to give the food industry the highest level of color quality control. Our ongoing commitment to innovation has led us to develop versatile and flexible technologies that combine precision with user-friendly designs to allow for easy, rapid, and accurate analysis of all sample types. Contact us for more information about our lineup of color measurement instruments, world-class customer service supports, and how we can help you make the most out of color.
Mr. Philips has spent the last 30 years in product development and management, technical sales, marketing, and business development in several industries. Today, he is the global market development manager for HunterLab, focused on understanding customer needs, providing appropriate solutions and education, and helping to solve customer color challenges across these industries and cultures.