Preparation and characterization of whey protein isolate-chlorophyll microcapsules by spray drying: effect of WPI ratios on the physicochemical and antioxidant properties

Publication date: Available online 12 September 2019Source: Journal of Food EngineeringAuthor(s): Zhi-Hong Zhang, Huadong Peng, Meng Wai Woo, Xin-An Zeng, Margaret Brennan, Charles S. BrennanAbstract:Whey protein isolate-chlorophyll (WPI-CH) microcapsules at different WPI ratios via spray drying were created to improve water solubility and biological stability of chlorophyll. Samples at a higher ratio of WPI resulted in a lower moisture content (1.14±0.12% to 2.47±0.09%), higher chlorophyll encapsulation efficiency (98.34±0.03% to 99.76±0.02%) and greater chlorophyll solubility (79.29±0.07% to 82.24±0.03%). The results of fluorescence and FT-IR spectra showed that the pyrrole ring of chlorophyll became bound to the hydrophobic residues of WPI leading to a change in the crystalline structure of chlorophyll, probably due to the formation of soluble complexes of WPI-CH. In addition, the antioxidant activity of fresh WPI-CH samples, and those stored for 6 months, increased by 19.75% and 18.51% respectively compared to WPI (p< 0.05). Therefore, WPI-CH prepared by the higher ratio of WPI can be used as a potential natural food additive because of its good antioxidant activity and physicochemical properties, especially water-solubility and stability.
Source: Journal of Food Engineering - Category: Food Science Source Type: research