Classifying Biocolours: Natural, Browning, and Additives

When you bite into a vibrant red strawberry yogurt or admire the golden crust of freshly baked bread, you’re witnessing the work of biocolours. These naturally derived pigments have transformed the food industry by providing safe, appealing alternatives to synthetic dyes. Understanding how biocolours are classified helps food manufacturers, scientists, and consumers make informed choices about the products they create and consume.

What are biocolours? 🔗

Biocolours are pigments obtained from biological sources such as plants, microorganisms, animals, and minerals. Unlike synthetic colors created through chemical processes in laboratories, biocolours are extracted from nature and often contain compounds with functional properties beyond simply adding color. The global shift toward natural food colors stems primarily from growing awareness about potential health concerns associated with artificial colors and increasing consumer preference for clean-label products.

Biocolours can be broadly classified into three major categories: natural colors, browning colors, and additives. Each category has distinct characteristics, sources, and applications in the food industry.

Natural colors: pigments from nature 🔗

Natural colors represent pigments extracted directly from biological sources without significant chemical modification. These colors have been used for centuries in culinary traditions worldwide.

Plant-derived natural colors 🔗

Plant sources provide the most abundant supply of natural colors in the food industry. Anthocyanins from berries, grapes, and red cabbage create red, purple, and blue hues. These water-soluble pigments are particularly valuable because they’re rich in antioxidants and change color based on pH levels, appearing red in acidic conditions and blue in alkaline environments.

Carotenoids provide yellow, orange, and red colors found naturally in carrots, tomatoes, and saffron. Beta-carotene extracted from carrots or the fungus Blakeslea trispora serves as a vitamin A precursor while coloring foods. Curcumin from turmeric offers a bright yellow color and is renowned for its medicinal properties. Chlorophyll extracted from green plants provides natural green coloring for various food applications.

Microbial sources of natural colors 🔗

Microorganisms have emerged as excellent biocolour producers, offering several advantages over plant sources. Production can be controlled year-round, independent of seasonal variations and climate conditions. Monascus pigments produced by Monascus fungi have been traditionally used in East Asian cuisines for centuries. Astaxanthin, a powerful red carotenoid, is produced by microalgae Haematococcus pluvialis and yeast Phaffia rhodozyma. Riboflavin produced by certain fungi and bacteria serves dual purposes as vitamin B2 and a natural yellow colorant.

These microbial pigments can be cultivated in controlled environments using fermentation technology, making them more sustainable and consistent than plant-based alternatives.

Browning colors: heat-induced pigments 🔗

Browning colors are produced during cooking processes through specific chemical reactions. These reactions not only create appealing colors but also develop complex flavors and aromas that make food more palatable.

The Maillard reaction 🔗

The Maillard reaction is a chemical reaction between amino acids and reducing sugars that creates melanoidins, the compounds responsible for the brown color and distinctive flavor of cooked foods. This non-enzymatic browning reaction typically proceeds rapidly at temperatures between 140 to 165°C (285 to 330°F).

The Maillard reaction produces the appealing brown color and flavors in seared steaks, toasted bread, roasted coffee, and baked goods. When foods reach temperatures above 285°F, this reaction begins to create hundreds of different flavor compounds that contribute to the characteristic taste of cooked foods. The reaction occurs in three stages: initial condensation of amino acids with sugars, intermediate dehydration and fragmentation, and final polymerization forming brown melanoidin pigments.

Caramelization 🔗

Caramelization is an entirely different process from the Maillard reaction, though results may appear similar. While the Maillard reaction involves amino acids, caramelization is the pyrolysis of sugars that typically starts at temperatures around 320°F (160°C) or higher, depending on the type of sugar. This process creates the characteristic brown color and sweet flavor of caramel, providing color and flavor to foods like caramelized onions, crème brûlée, and dulce de leche.

Biocolour additives: commercial applications 🔗

Biocolour additives include commercially processed natural colorants used in food manufacturing. These additives are regulated and approved for safe use in food products.

Anthocyanins as food additives 🔗

Anthocyanins have become increasingly popular as food additives. The commercial additive E163 is commonly derived from grape skin and used to create purple-colored jams, confectioneries, and beverages. Recent concerns about synthetic food dyes and their effects on neurological functions and behavioral effects have accelerated the shift toward anthocyanin-based colorants.

Anthocyanins offer value-added properties beyond coloring. They possess antioxidant, antimicrobial, and anti-inflammatory properties, making them multifunctional food ingredients. However, their stability can be challenging, as they tend to degrade quickly due to light, oxygen, temperature, and pH changes.

Other natural color additives 🔗

Beyond anthocyanins, several other natural colorants serve as approved food additives. Annatto (E160b) extracted from achiote seeds provides yellow to orange colors. Beetroot extract offers red to purple hues for frozen and short shelf-life products. Carmine (E120) derived from cochineal insects provides bright red coloring, though its animal origin makes it unsuitable for vegetarian or vegan products.

Why biocolours are preferred over synthetic dyes 🔗

The preference for biocolours over synthetic dyes stems from multiple factors centered on safety, health benefits, and consumer acceptance.

Safety and regulatory approval 🔗

Natural colors are generally considered safer than synthetic alternatives when consumed at typical dietary levels. Regulatory bodies including the Food Safety and Standards Authority of India (FSSAI), European Food Safety Authority (EFSA), and the U.S. Food and Drug Administration (FDA) have established frameworks for approving and monitoring biocolours. Natural colorants are assumed safe if they’re non-allergic, non-toxic, non-carcinogenic, and biodegradable.

Antioxidant and health benefits 🔗

Unlike synthetic dyes that serve only aesthetic purposes, many biocolours provide significant health benefits. Anthocyanins demonstrate strong antioxidant properties, helping to reduce oxidative stress at cellular and organismal levels. Studies show anthocyanins can help prevent cardiovascular diseases, support visual health, and provide anti-inflammatory effects. Carotenoids not only color foods but also function as vitamin A precursors and antioxidants.

The antioxidant capacity of natural colorants helps protect both the food products they’re added to and consumers who ingest them. This dual benefit makes biocolours particularly valuable in functional food applications.

Consumer acceptance and clean labeling 🔗

Modern consumers increasingly scrutinize food labels, seeking products with recognizable, natural ingredients. Consumer demand for natural colors is predicted to increase by 7% annually, driven by the clean-label movement. Biocolours align with consumer preferences for transparency and natural ingredients, giving manufacturers a competitive advantage in the marketplace.

The shift from synthetic to natural colorants reflects broader changes in consumer attitudes toward food processing and artificial ingredients. Products labeled with natural colorants like “colored with fruit and vegetable extracts” resonate more positively with health-conscious consumers than those listing synthetic dye numbers.

Challenges and future directions 🔗

Despite their advantages, biocolours face certain challenges. Natural pigments often exhibit lower stability than synthetic dyes, particularly when exposed to light, heat, and varying pH levels. They can be more expensive to produce and may create inconsistent coloring across different production batches. Some natural colorants, like those from beetroot, have limited stability in certain applications.

However, ongoing research addresses these limitations through encapsulation technologies, improved extraction methods, and discovery of new microbial sources with enhanced stability. Acylated anthocyanins, for example, demonstrate higher stability than their non-acylated counterparts, making them more suitable for commercial food applications.

What do you think? As food manufacturers continue developing more stable and cost-effective natural colorants, how might this shift affect your food choices? Would you be willing to accept slightly different shades in your favorite products if it meant using only natural colors instead of synthetic dyes?

References

1. https://www.researchgate.net/publication/280492266_Biocolors_The_New_Generation_Additives
2. https://www.healthline.com/nutrition/anthocyanin
3. https://www.foodresearchlab.com/blog/new-food-product-development/natural-food-colour-and-its-current-research-trends/
4. https://pmc.ncbi.nlm.nih.gov/articles/PMC4745522/
5. https://www.foodrepublic.com/1294310/real-difference-between-maillard-reaction-caramelization/
6. https://pmc.ncbi.nlm.nih.gov/articles/PMC5613902/
7. https://www.mdpi.com/1422-0067/25/22/12001
8. https://www.frontiersin.org/articles/10.3389/fnut.2019.00007/full