The Blue Storm is Coming: The Rise and Charm of Natural Blue Pigments
Starting from the significant move of the FDA to approve butterfly pea flower extract as a food colorant, this article discusses the scarcity of natural blue pigments and their importance in the food industry. It also introduces various natural sources of blue, introduces the characteristics, extraction methods, and applications of different blue pigments such as gardenia blue, phycocyanin, ect.
On September 2, 2021, the U.S. Food and Drug Administration (FDA) issued Regulation 2021 - 18995, proposing to approve an aqueous extract of butterfly pea flower as a color additive in some foods. In the natural world where pure natural blue pigments are extremely scarce, it is truly remarkable to discover a natural blue raw material that is safe, reliable, and suitable for the food industry. This action by the FDA marks a significant advancement in the industrial development of natural blue pigments following phycocyanin, and it can be regarded as a milestone "breakthrough" in the history of food and beverage development.
In the world of colors, blue, as one of the three primary colors in nature, is a key element for formulating various shades. However, the natural sources of blue pigments are extremely scarce. External factors such as high temperatures, light, and changes in pH value can all lead to their instability. Coupled with the high production costs, natural blue pigments have always struggled to stand out in the market and truly become the "main character." But under the current consumer trend of pursuing natural and healthy products, the demand for natural blue/green pigments from food manufacturers continues to rise, and the supply in both domestic and international markets has always been unable to meet this strong demand.
Compared with colors such as red, yellow, and green that are widely found in nature, blue always appears mysterious and unique. Humans are fond of noble sapphires, yet they are somewhat wary of blue foods. Why doesn't the principle of "rarity makes things precious" apply to the colors of food? What kind of difficulties has humanity experienced in the process of exploring natural blue pigments? Can the blue pigment from butterfly pea flowers help blue foods enter people's daily lives and become regulars on the dining table?
In recent years, the rise of the "clean label" concept has effectively promoted the rapid development of the natural pigment market. According to data from Meticulous Research, the market size of natural food colorants is expected to reach 3.2 billion U.S. dollars by 2027. Predictions by Fact.MR also show that the compound annual growth rate of the global natural food colorant market during the period from 2019 to 2029 will exceed 5%.
Compared with artificial pigments, natural pigments have many advantages such as safety, reliability, no toxic side effects, natural tones, and multifunctionality, and their raw materials are widely sourced. However, most of the natural pigments extracted from common food ingredients are mainly in red and yellow tones, and blue pigments are extremely rare.
Despite the limited choices of natural blue pigments, their bright and vivid colors have become a novel and fashionable element influencing market trends in recent years, attracting the attention of consumers of all ages. Blue ice creams, blue candies, blue pastries... Various food and beverage products with blue as the main tone have appeared on the market one after another. Driven by the consumption concept of "colorful food," they have received increasing popularity.
The color research institution Pantone released the color of the year 2020 as Classic Blue. GNT, an internationally leading natural pigment supplier, also designated the trend color for food and beverages in 2020 as "Shades of Aqua." These predictions of color trends instantly pushed the blue color series to the forefront of fashion, triggering extensive attention and discussions. Some people quickly became fans of it, while others held different opinions.
In nature, natural blue is distributed in various organisms. In addition to butterfly pea flowers, there are also blueberries rich in fiber and vitamin C, blue cheese with naturally mottled blue spots formed by mold, the edible fungus Lactarius indigo native to North America and East Asia, and even the commonly seen black or orange caviar also has a blue variety. As a food ingredient on the dining table that combines classic and trendy elements, blue caviar has a unique flavor with a salty and fresh taste of the ocean. Under the creative pairings of chefs, it has evolved into many novel ways of eating, showcasing its unique charm.
For foods that do not have a natural blue color but need blue elements to enhance their attractiveness, the rational use of blue pigments becomes crucial. Three types of blue pigments extracted and processed from plants, namely gardenia blue, phycocyanin, and butterfly pea flower blue, each have their own characteristics in food applications.
The source of gardenia blue is relatively unique. It uses the fruits of the gardenia plant of the Rubiaceae family as raw materials. Gardenia trees are widely cultivated in China, and their fruits are small and delicate, oval in shape and orange in color, just like small jewels hanging on the branches. The production process of gardenia blue is full of technological content. First, geniposide is extracted from gardenia fruits, which is the key substance for the formation of gardenia blue. Subsequently, through a special enzymatic reaction, geniposide undergoes a wonderful transformation, and finally, a stable blue pigment - gardenia blue is produced.
Gardenia blue has the characteristics of being resistant to acids, alkalis, and high temperatures, which gives it a wide range of application potential in food processing. Although it is rarely directly used for coloring foods, it is an expert in color formulation. It is mainly paired with natural yellow pigments such as gardenia yellow and safflower yellow to create green colors of different shades, just like a painter mixing colors, adding unique tones to foods. In foods such as hard candies, biscuits, cake premixes, whipped cream, ice creams, dairy products, and beverages, you can see the unique colors formulated by gardenia blue. In addition, it can also be combined with various natural red pigments to formulate purple colors of different shades, further enriching the color options for foods.
Phycocyanin pigments are usually extracted from algae plants such as Spirulina, cyanobacteria, and Nostoc. During the extraction process, the plant cells are first broken to dissolve phycocyanin into the extraction solution, and then through steps such as precipitation and separation, the final product is obtained. As an extremely rare protein pigment in nature, phycocyanin not only has a bright color and is rich in essential amino acids for the human body, but it can also regulate and synthesize various important enzymes required for human metabolism, enhance the immune system function, and play an important role in inhibiting the growth of cancer cells and promoting the regeneration of human cells. Therefore, phycocyanin is vividly called the "diamond of food" by food experts.
Butterfly pea flowers, also known as blue butterflies and blue flower beans, are native to tropical Asia. Nowadays, their beautiful figures can also be seen in some southern regions of China. The blue pigment of butterfly pea flowers is extracted from butterfly pea flowers. When these flowers are in full bloom, they are just like blue butterflies dancing on the branches, which is very beautiful. The blue pigment of butterfly pea flowers has good applicability and stability. In products with a pH value higher than 3.8, it will present a vivid denim blue, and the color is very close to the synthetic pigment "indigo." This characteristic makes it very popular in the beverage field. Many businesses use it to make blue beverages, such as blue cocktails and blue fruit juices. These beverages, with their unique blue appearance, have attracted the attention of a large number of consumers.
The blue pigment of butterfly pea flowers not only performs well in the food field but also has certain health benefits. Butterfly pea flowers are rich in anthocyanins and various vitamins, which are helpful for protecting eyesight, improving immunity, promoting skin elasticity and collagen production, and have antioxidant effects. They can be used as antioxidants and enzyme stock solutions with the effect of protecting eyesight. In some beauty products, extracts of butterfly pea flowers are also added, taking advantage of their antioxidant and skin health-promoting properties to provide care for the skin.