Natural Colorants: Unlocking the Future Through Fungal Innovation and Mass Spectrometry

As consumer demand continues to shift toward clean-label, plant-based, and minimally processed foods, industries are facing new challenges in how colorants and additives are sourced, characterized, and scaled. Synthetic dyes—once favored for their vividness and consistency—are increasingly being replaced by natural alternatives with functional benefits. But not all “natural” options are created equal, especially when it comes to stability, scalability, and safety.

Enter fungal pigments. These complex compounds, produced by microorganisms such as Monascus and Talaromyces species, are rapidly emerging as a compelling solution. Their appeal lies not only in their vibrant hues and potential health benefits, but also in the fact that fungal fermentation offers better yields, consistency, and control compared to traditional plant or animal sources. Yet the path from promising organism to industrial ingredient requires deep analytical insight—and that’s where mass spectrometry steps in.

Fungal pigments and their benefits

Fungi, especially filamentous species, are becoming a focal point for researchers seeking stable, tunable, and scalable natural pigments. Microbial colorants like azaphilones, carotenoids, and melanins offer broad-spectrum coloration and can be produced year-round, independent of agricultural variability.

But safety concerns have historically hindered broader adoption—particularly around Monascus-derived pigments, which can co-produce unwanted byproducts like citrinin (a known mycotoxin). That’s why newer candidates such as Talaromyces atroroseus are gaining traction. Unlike Monascus, T. atroroseus produces red and yellow pigments without generating harmful metabolites, making it a safer platform for food-grade pigment development.

Mass spectrometry provides clarity about fungal pigments

Identifying and characterizing new pigment families from microbial cultures is a task that hinges on high-precision, high-sensitivity analytical tools. In a recent study led by researchers at the Technical University of Denmark, scientists cultivated T. atroroseus under controlled fermentation conditions and uncovered a previously uncharacterized class of red pigments—now known as atrorosins.

The analysis relied on a combination of techniques:

• Real-time gas analysis to ensure optimal fermentation conditions (e.g., oxygen, carbon dioxide, ethanol levels),
• Ultra-high-performance liquid chromatography with diode array detection (UHPLC-DAD) for pigment profiling,
• High-resolution tandem mass spectrometry (HRMS/MS) to determine molecular composition, and
• Nuclear magnetic resonance (NMR) to elucidate structural details.

Magnetic sector mass spectrometers—like those used to sample multi-stream bioreactors in this study—enable precise tracking of gaseous metabolites, helping to ensure a tightly controlled environment for biosynthesis. This monitoring is critical when investigating how changes in nutrients (such as the addition of different amino acids) affect the pigments produced.

Atrorosins: Tailored Pigments Through Amino Acid Supplementation

One of the study’s key findings was that the structure and identity of the pigments produced could be tuned by supplying different amino acids as nitrogen sources during fermentation. Most atrorosins incorporated the specific amino acid present in the media into their pigment core, resulting in distinct molecular structures.

Interestingly, these new pigments appeared predominantly in the cis-isomeric form, which researchers hypothesized was influenced by steric hindrance during biosynthesis. This kind of detailed insight isn’t possible without advanced analytical characterization—further underscoring the importance of tools like mass spectrometry in natural product discovery.

Looking Ahead

The ability to produce customizable, high-performance colorants through microbial fermentation represents a major step forward for the food and beverage industry. It opens the door to natural pigments that are not only vibrant and stable but also safe and scalable—qualities that will be critical as regulations tighten and consumer expectations evolve.

Mass spectrometry is proving to be an indispensable part of this journey. By enabling real-time metabolic monitoring, molecular identification, and structure elucidation, these technologies help researchers move beyond trial-and-error and into data-driven pigment development.

As interest grows in biologically sourced ingredients—from flavor compounds to functional additives—analytical science will continue to play a defining role in bridging the gap between microbial potential and commercial application.