🏳️🌈 Europe’s “Living Color”: Why Natural Pigments Also Need an “Activity Retention Rate” Test
Headline: Adding natural pigment isn’t the end of the story — Europe’s organic sector is starting to ask: “Does it stay alive after processing?”
Many people assume “natural pigments = healthy” and “synthetic pigments = unhealthy.” However, there’s an often-overlooked issue in between: after natural pigments enter a factory and go through heating, pH adjustment, sterilization, and storage, both the color molecules and their physiological activity can be compromised.
Take anthocyanins as an example (found in blueberries, purple sweet potatoes, mulberries, and grape skins). They are a type of water-soluble plant pigment with a notoriously “volatile” nature. They appear red in acidic environments, purple near neutral, and turn blue or even colorless chalcones in alkaline conditions. High temperatures, light, oxygen, certain metal ions, and even contact with ascorbic acid (vitamin C) can accelerate their degradation. Therefore, two products both labeled “colored with anthocyanins” can differ greatly: one may look vibrant when it leaves the factory but darken within two weeks; another may lose half its color after undergoing beverage pasteurization. This isn’t necessarily “cutting corners” by the manufacturer, but rather a significant difference in stabilization technology.
In recent years, as Europe pushes for “clean labels,” consumers not only want colors “derived from plants” but also want to know “if they still retain their original plant value.” Industry reports on the European natural pigment market note that buyers increasingly prioritize traceability, transparency, organic certification, and adherence to trade guidelines. In this trend, if a voluntary label like “Living Color” were to emerge, its logic would be:
- The pigments used must primarily come from natural sources such as plants, microorganisms, or minerals, rather than synthetic azo compounds.
- Suppliers must prove that “a significant proportion of intact anthocyanins remains after processing,” rather than just leaving behind discolored or degraded by-products.
- They must provide test reports on activity retention rate, post-heat-treatment retention, and retention under simulated digestion.
How is this achieved technically? Three common approaches:
- Microencapsulation: Using gum arabic, maltodextrin, whey protein, sodium alginate, etc., to encapsulate the pigment, reducing direct contact with heat, light, and oxygen. For instance, spray- or freeze-drying mulberry anthocyanins with whey protein and maltodextrin/gum arabic can achieve encapsulation rates around 90%, significantly reducing heat-treatment losses.
- Protein/Polysaccharide Complexation: Egg albumin, casein, chitosan, pectin, etc., form complexes with anthocyanins, improving thermal and intestinal stability.
- Liposomes/Nanoparticles: Loading anthocyanins into nanoliposomes or protein nanoparticles has been shown in studies to yield higher retention rates in simulated intestinal digestion compared to free anthocyanins.
For the average consumer, the significance is straightforward: a label like “Living Color” doesn’t mean “it cures diseases,” but it does mean the natural color you’re paying for is less likely to become “just color with none of the plant’s original benefits” during processing. When checking ingredients, look for specific names like “grape skin red/anthocyanins/purple sweet potato color” rather than the vague term “natural color,” and check if stabilization processes or batch testing are indicated.
👶 Baby Food “Zero Migration” Concept: Natural Colors Must Also Be Stable and Not “Run Away” in the Stomach
Headline: Coloring baby food isn’t just about being “natural” — why we need to look at “whether it runs off in the stomach or intestines, and if it’s properly encapsulated”
The pain points for infant and baby complementary foods are different from those for adults: a baby’s liver, kidneys, and gut microbiome are still developing, so the simpler and more stable the ingredient list, the more reassuring it is for parents. Many parents feel relieved seeing “natural pigments,” but “natural” doesn’t mean the pigment behaves perfectly from mouth to stomach.
Here’s a simple example: if you add anthocyanins directly to fruit puree, the color might fade during heat sterilization. In the acidic environment of the stomach, it may partially transform, and then in the intestinal fluid, it faces further “modification” from bile salts, enzymes, and pH changes. If the pigment isn’t stabilized, two scenarios can occur — either the color becomes unstable after processing, prompting manufacturers to add more, or it releases and degrades too quickly in digestion models, making dosage control and product consistency difficult.
This is why the industry is seeing concepts like “zero migration/low migration” internal standards: using simulated gastric fluid and simulated intestinal fluid to test when and how much the pigment is released, and whether it “runs away” at the wrong stage. Public literature more commonly evaluates this using terms like “encapsulation rate,” “retention rate,” and “simulated digestion bioaccessibility.” For anthocyanins, the solutions include:
- Microencapsulation: Sealing the pigment into tiny spheres (a few to tens of microns) using wall materials like gum arabic, maltodextrin, and whey protein, then spray-drying it for easy addition to rice cereal, fruit puree, or biscuits.
- Protein Embedding/Nano-composites: Using whey protein, egg white protein, casein peptides, chitosan, etc., to combine with anthocyanins. There are reports of mulberry anthocyanin-egg white protein nanoparticles achieving over 82% encapsulation rates, with better simulated intestinal digestion retention than non-encapsulated versions.
- Liposomes/Chitosan Nanoparticles: These offer greater resistance to heat, light, and metal ions, with some formulations improving retention in the intestinal tract.
In practice, domestic baby food standards may not be called a “zero migration guide,” but they are reflected in several measures: selecting usable pigments according to GB 2760 and relevant infant food standards, minimizing or avoiding unnecessary coloring; using organic, traceable fruit purees instead of “pure color extracts”; microencapsulating prone-to-fading anthocyanins and beet reds before adding them to formulas; and conducting factory acceleration tests, sterilization tests, and simulated digestion tests. It’s easy for brands to claim “no artificial colors” in their marketing, but the real challenge is clearly stating “how much is lost during processing after adding natural pigments, and how much the baby consumes in each bite.”
When purchasing, parents can focus on three lines of information: the ingredient list should name the pigment specifically (e.g., grape skin red, beta-carotene, beet red, etc.), not just “food coloring”; look for “no artificial synthetic colors” alongside coloring from fruit puree/vegetable powder itself; if a product highlights “stabilized anthocyanins,” ask customer service for encapsulation rate or heat retention reports — you don’t necessarily need a strict 5% metric, but third-party testing is more reliable than a verbal claim of “natural.”
