Food dyes and colorants are found in many of our favorite foods and beverages, and there’s growing interest in shifting from artificial to natural options. Precision fermentation offers a new way to produce these same color molecules using microorganisms. In this blog, we explore how it works and what it means for food dyes.
Top Takeaways
- Precision fermentation uses microorganisms, like yeast or bacteria, to produce specific compounds, including food colorants.
- Instead of extracting dyes from plants or synthesizing them chemically, microbes are genetically modified to make the same molecules through controlled fermentation.
- These colorants are chemically identical to their natural counterparts and are evaluated for safety using the same risk assessment frameworks as other food ingredients.
- This approach can improve consistency, sustainability, and supply stability compared to traditional dye production methods.
What is precision fermentation?
Precision fermentation is a process that uses microorganisms, such as yeast, fungi, or bacteria, to produce specific compounds.
Scientists provide these microbes with genetic instructions that direct them to make a target ingredient. This is done using genetic engineering, where specific DNA sequences are introduced or modified so the organism can biosynthesize a desired molecule.
Fermentation has been used for thousands of years to make foods like bread, beer, and yogurt. Precision fermentation builds on that foundation but allows for much greater control over what is produced.
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How does precision fermentation apply to food dyes?
Food dyes are molecules that absorb and reflect light, giving foods their color. Traditionally, these come from two main sources:
- Natural dyes (e.g., beet juice, turmeric, spirulina)
- Synthetic dyes made through chemical processes
Precision fermentation offers a third path.
Instead of extracting pigments from plants or synthesizing them chemically, scientists can engineer microorganisms to produce the same pigment molecules.
For example, microorganisms can be used to produce:
- Anthocyanins (reds, purples, blues found in berries)
- Carotenoids (yellows and oranges found in carrots)
- Betalains (reds and yellows found in beets)
What does the precision fermentation process look like?
At a high level, the process works like this:
- Identify the target pigment: Scientists determine the exact molecule responsible for a color.
- Design the genetic pathway: The genes responsible for producing that molecule are identified and introduced into a microbial host.
- Fermentation: Typically, microorganisms are grown in controlled tanks, similar to brewing, where they convert nutrients such as sugar into the target pigment.
- Harvest and purification: The pigment is extracted and purified for use in food products.
The result is a highly consistent ingredient that can be produced at scale.
Are dyes created from precision fermentation “natural”? Are these colorants safe?
The molecule produced through precision fermentation is often chemically identical to the one found in nature. However, because it is made using a genetically engineered microorganism, how it is labeled depends on regulatory definitions and jurisdiction.
From a safety perspective, what matters most is:
- The identity of the compound
- The dose (how much is consumed)
- The exposure over time
This is the same framework used to evaluate any food ingredient.
Why use precision fermentation for colorants and food dyes?
There are several reasons companies are exploring this approach:
Consistency: Natural color extraction can vary based on weather, soil conditions, and crop variability. Fermentation produces more uniform results batch-to-batch because the same genetically modified microorganism is used in each batch.
Sustainability: Producing pigments via microorganisms can reduce land use, lower water consumption, and decrease reliance on large-scale agriculture for specific crops.
Supply stability: Crop failures or seasonal limitations can affect the availability of natural dyes. Fermentation allows for year-round production.
Innovation: Some colors are difficult to extract or stabilize from natural sources. Precision fermentation can enable access to pigments that are otherwise impractical to produce.
How are these ingredients derived from precision fermentation evaluated for safety?
Whether a colorant is plant-derived, synthetic, or produced through fermentation, it must undergo safety evaluation before being used in food.
In the United States, this may involve:
- Review under the U.S. Food and Drug Administration
- Determination of whether the substance is approved as a color additive or considered Generally Recognized As Safe (GRAS)
Safety assessments consider:
- Toxicology data
- Estimated dietary exposure
- Metabolism and elimination
- Weight of evidence across studies
The key principle remains that hazard alone does not determine risk; exposure matters.
Are natural food dyes safer than food dyes made through precision fermentation?
Dyes made through precision fermentation are not inherently safer than those derived from natural sources; however, the process offers greater control over purity and consistency.
Because fermentation occurs in controlled environments, it may reduce variability and the likelihood of certain environmental contaminants compared to agricultural extraction, but both types of colorants are subject to purification steps and safety evaluations.
Ultimately, safety depends on the final ingredient, its purity, and exposure, not whether it was produced by fermentation or extracted from nature.
What about the public perception of these food dyes derived from precision fermentation?
Precision fermentation sits at the intersection of science, food, and technology, areas that are frequently subject to confusion online.
Some common misconceptions include:
- That “fermentation-made” equals synthetic or unsafe
- That genetic engineering automatically introduces risk
In reality, safety is determined by what the final ingredient is and how much of it is consumed, not the method used to produce it.
The good news
Precision fermentation enables the production of familiar food color molecules with greater control, consistency, and potentially lower environmental impact. At the same time, these ingredients are evaluated using established safety frameworks that focus on dose, exposure, and overall evidence.
If you have any questions about ingredients or ideas for a blog post, please send us an email or submit your idea to us at go.msu.edu/cris-idea.
Citations and Further Reading
Eastham, J. L., et al. (2024). Precision fermentation for food proteins: Ingredient production, process, and regulatory considerations. Current Opinion in Food Science.
https://doi.org/10.1016/j.cofs.2024.101060
Finkel, E. (2024, July). Precision fermentation can be used for food colorings, too. Food Technology Magazine, Institute of Food Technologists.
https://www.ift.org/news-and-publications/food-technology-magazine/issues/2024/july/columns/ift-first-precision-fermentation-for-food-colorings
Sen, T., Barrow, C. J., & Deshmukh, S. K. (2019). Microbial pigments in the food industry—Challenges and opportunities. Frontiers in Nutrition, 6, 7.
https://doi.org/10.3389/fnut.2019.00007
Singh, T., Kaur, G., & Kaur, H. (2023). Natural bio-colorants and pigments: Sources and applications. Food Chemistry Advances, 2, 100203.
https://doi.org/10.1016/j.focha.2023.100203