April 2021
Vol 7, Issue 15

About The Cover

Cover image expansion

ONLINE COVER Several research programs around the world are dedicated to the hunt for a natural alternative to FD&C Blue No.1—a challenging effort given that cyan blue is one of the rarest colors in nature. While previous research has shown that red cabbage anthocyanins produce a vibrant blue color in a pH-neutral solution, this color has been too violet to replace artificial blue dye. Studies have further found that Peak 2 (P2), a minor mono-acylated anthocyanin, warrants further investigation, yet this compound contributes less than 5% of red cabbage's total anthocyanin content. To further explore the potential of anthocyanins as a blue colorant, Denish et al. incubated P2, as well as anthocyanins P5 and P8, with aluminum cations, finding that only the P2 solution produced the desired blue color. Next, the researchers tested the color stability of blue colorant developed from P2, observing that while many naturally sourced colorants have limited stability over time, its color only diminished by 14% in sugar syrup over 55 days. Finally, Denish et al. identified a hydrolytic enzyme that converts the red cabbage anthocyanins P6, P7, and P8 into P2, addressing the need to obtain sufficient quantities of P2 to develop a food coloring agent. The authors note that toxicity studies will be needed to define the novel colorant's usage limitations and food safety precautions, and further research will be required to evaluate its stability and color in a wide range of applications. [CREDIT: ANILAKKUS/ISTOCK]