Improvement of Anthocyanin Stability in Butterfly Pea Flower Extract by Co-pigmentation with Catechin

¹ Food Engineering Department, Faculty of Engineering, King Mongkut’s University of Technology Thonburi, Bangkok, Thailand
² Mechanical and Process Engineering, TGGS, King Mongkut’s University of Technology North Bangkok, Bangkok, Thailand
³ Food Technology and Engineering Lab, PDTI, King Mongkut’s University of Technology Thonburi, Bangkok, Thailand
⁴ Food Science Department, National Pingtung University of Science and Technology, Pingtung, Taiwan

^* Corresponding author: suvaluk.asa@kmutt.ac.th

Abstract

Most of the food processing operations involve the use of heat which generally causes alteration, and degradation of natural pigments, resulting in lower stability. One of the stability enhancement methods is co-pigmentation. This study aimed to determine effect of catechin co-pigment on stability of anthocyanins in Clitoria ternatea (or butterfly pea flower) extract. Degradation kinetics of anthocyanins in the extract were evaluated at three temperatures (28, 60, and 90℃). The effect of co-pigment ratio (catechin: anthocyanins at 1:1, 50:1 and 100:1 by weight) on the stability of anthocyanin extract at 90℃ was determined by the pH differential method. It was found that anthocyanin degradation followed the zero- order kinetics at all temperatures; the degradation rate increased as the temperature increased. At a lower pH, anthocyanins became more stable. An increase in the co-pigment ratio significantly retarded the degradation anthocyanins at 90℃. In addition, co-pigmentation also intensified the color of butterfly pea extract. The highest anthocyanin stability was obtained at co-pigment ratio of 100:1.