Blue is one of the rarest colors in nature and one of the hardest to reproduce in food without synthetic dyes. But researchers at Cornell University may have found a game-changing solution.
A new study published in Food Hydrocolloids describes how scientists used a protein from algae to create a more stable, vibrant blue dye that could one day replace petroleum-based artificial colorants in everything from ice cream to cereals. Better still, this natural dye could also function as an emulsifier and antioxidant, offering a multipurpose clean-label option that food manufacturers increasingly want.
“Consumers don’t want artificial ingredients in their food,” said Qike Li, first author on the study and a doctoral candidate in Cornell’s Department of Food Science. “They want something healthier and more natural. Specifically, they want to see a ‘clean label,’ which is a major reason we have chosen to work to increase the functionality of phycocyanin.”
Phycocyanin (PC), the algae protein at the heart of the research, is already used in some natural food products, including as a coloring agent in specialty versions of candies like M&M’s. But in its raw form, it’s unstable as it’s sensitive to heat during food processing and light during storage. That makes it difficult to use widely, especially in products that need to hold up over time.
To solve that, the Cornell team broke phycocyanin down into smaller, more uniform particles using a denaturing agent. The result was a version of the protein that holds its color better and has increased emulsifying capacity, meaning it can help blend oil and water, just like synthetic emulsifiers often used in processed foods.
“It’s like using a magnifying glass to see and understand changes in protein structure,” said senior author Alireza Abbaspourrad, PhD. “Our aim is to increase the functionality of phycocyanin as a colorant, emulsifier and antioxidant, so that on the list of ingredients, it could replace multiple synthetic items.”
The timing could be significant. Several states are moving to ban synthetic food dyes such as Red No. 3, Blue No. 1 and Yellow No. 5 due to concerns about potential health effects, especially in children. Meanwhile, U.S. Secretary of Health and Human Services Robert F. Kennedy Jr. has proposed a national plan to phase out some artificial dyes altogether.
While many consumers welcome these changes, the food industry faces a challenge: natural blue is notoriously tricky. Most blue hues in nature, like a morpho butterfly’s wings or the sky, aren’t pigments at all, but optical effects created by the way light scatters. That’s why natural blue colorants are harder to stabilize and often more expensive.
Phycocyanin, extracted from algae like spirulina, has long been a promising candidate. But this new formulation could make it far more useful and cost-effective.
Abbaspourrad believes it’s a realistic option.
“The cost associated with adoption of phycocyanin in place of artificial blue dyes is likely reasonable, considering its health benefits,” he said.
The next step is partnering with industry to scale the innovation and possibly bring it to a grocery shelf near you.
This research was funded by the U.S. Department of Agriculture and conducted by scientists at Cornell University’s College of Agriculture and Life Sciences.