Food colorants play a vital role in making our meals visually appealing, and among them, macromolecular colorants—derived from natural sources like algae, plants, and microbes—are gaining popularity for their safety and clean-label appeal. However, their unique properties raise questions about stability, cost, and application. In this guide, we answer the top 10 FAQs about macromolecular food colorants, covering safety, usage, and future trends—helping manufacturers and consumers make informed choices.

Q1. What is the difference between macromolecular colorants and small molecule colorants?

Answer:

Molecular weight: The molecular weight of macromolecular colorants (such as phycocyanin and chlorophyll protein complex) is usually more than a few thousand Daltons, while that of small molecules (such as lemon yellow and carmine) is generally in the hundreds of Daltons.

Source: Macromolecules are mostly extracted from natural sources (such as plants and microorganisms), while small molecules may be natural or synthetic.

Stability: Macromolecules are more sensitive to pH and temperature, while small molecules are generally more stable.

Q2. Are macromolecular colorants safe? Will it be absorbed by the human body?

Answer:

Most macromolecular colorants (such as phycocyanin) are not easily absorbed directly by the intestines due to their large molecular weight, and may be metabolized after degradation.

Safety needs to be certified by international authoritative organizations (such as EFSA, FDA), and legally used varieties are safe at limited doses.

Q3. Why are macromolecular colorants more expensive?

Answer:

Difficulty of extraction: It needs to be separated and purified from natural organisms (such as phycocyanin extracted from spirulina), and the process is complicated.

Stability issues: It may be necessary to add protective agents or special packaging, which increases costs.

Q4. Will macromolecular colorants cause allergies?

Answer:

Possible allergens exist in protein pigments (such as phycocyanin), but they are safe for most people.

People with allergies need to check the ingredient list to avoid known allergens.

Q5. What foods are common macromolecular colorants?

Answer:

Phycocyanin (blue): ice cream, beverages, candy.

Sodium copper chlorophyllin (green): chewing gum, cakes.

Monascus red (red): meat products, fermented bean curd.

Q6. Will macromolecular colorants decompose at high temperatures?

Answer:

Most macromolecules (such as proteins) are sensitive to heat and may fade or denature at high temperatures.

When applied, a heat-resistant process (such as microencapsulation) or later addition is required.

Q7. How to identify whether macromolecular colorants are used in food?

Answer:

Check the label: the name is marked in the ingredient list (such as "phycocyanin" and "chlorophyll").

Natural pigments are usually marked with E numbers (such as E140 for chlorophyll) or simply written as "natural colorants".

Q8. Are macromolecular colorants suitable for vegetarian or vegan foods?

Answer:

Most plant/microbial sources (such as phycocyanin, anthocyanins) are suitable for vegetarians.

Note that animal-derived pigments (such as cochineal red) are not macromolecules and are not vegetarian.

Q9. Will macromolecular colorants react with other ingredients?

Answer:

Maybe! For example:

pH effect: anthocyanins change color in acidic (red) and alkaline (blue) conditions.

Metal ions: Chlorophyll may change stability when it encounters copper and iron.

Q10. What is the development trend of macromolecular colorants in the future?

Answer:

Microbial fermentation production: such as genetically engineering yeast to produce pigments to reduce costs.

Functional compounding: Development of pigments with both coloring and nutritional (such as antioxidant) functions.

Clean label: Consumers prefer "natural, no additives", which drives the demand for macromolecular natural pigments.

Macromolecular colorants are popular because of their naturalness and high safety, but cost and stability are challenges. When choosing, it is necessary to consider the food process requirements and regulatory compliance.