Phycocyanin is a blue water-soluble pigment extracted from spirulina, also called blue spirulina powder . It is also one of the rare pigment proteins in nature. It is not only bright in color, but also a nutritious protein with complete amino acid composition. At the beginning of the 21st century, it has been widely used as high-grade natural pigments in food and cosmetics in Europe, America, Japan and other countries. Phycocyanin is a natural blue pigment approved and is also listed as a color food raw material in the European Union, and its use is not restricted. Phycocyanin powder can be used as food colorant. And itself is a very rich protein, its amino acid composition is complete, essential amino acid accounted for 37.2% of the total. It is a natural blue pigment approved by FDA. At present, red and yellow pigments…