Effect of inlet air drying temperatures on the physicochemical properties and antioxidant activity of whey protein isolate-kale leaves chlorophyll (WPI-CH) microcapsules

Abstract The whey protein isolate-kale leaves chlorophyll (WPI-CH) microcapsules were prepared by spray drying in this work. Results from Fourier transform infrared spectra (FT-IR) showed that WPI-CH microcapsules were successfully obtained by forming the hydrogen bonds between WPI and chlorophyll, which resulted in shifting of the absorption band at 1074 cm−1 to 1078 cm−1 with a new absorption band revealed in 1049 cm−1. Effect of inlet air drying temperatures on the physicochemical properties and antioxidant activity of WPI-CH microcapsules were investigated. The result revealed that the moisture content of WPI-CH (20% addition) microcapsule was decreased by 21.1% with the inlet air drying temperature increased from 120 to 180 °C. Moreover, the encapsulation efficiency and solubility of chlorophyll were enhanced by 3.78% and 7.79%, respectively. Furthermore, DPPH scavenging capacity of WPI-CH microcapsules under different addition of chlorophyll were increased from 42.9% to 74.3%, 52.7%–82.7% and 71.8%–85.3%, respectively.