Effects of different drying methods on the structures and functional properties of phosphorylated Antarctic krill protein

• Published in: Journal of Food Science
• Main Authors: Lin, Na, Liu, Baolin, Liu, Zhidong, Qi, Ting
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2020
• Subjects: Antarctic; Antarc*; Antarctic Krill
• Online Access: http://dx.doi.org/10.1111/1750-3841.15503; https://onlinelibrary.wiley.com/doi/pdf/10.1111/1750-3841.15503; https://onlinelibrary.wiley.com/doi/full-xml/10.1111/1750-3841.15503

Abstract Antarctic krill protein (AKP) was extracted from Antarctic krill by an alkali dissolution‐isoelectric precipitation method and then it was phosphorylated with sodium tripolyphosphate. The phosphorylated Antarctic krill protein (P‐AKP) powder was obtained by spray‐drying (SD), freeze‐drying (FD), and hot‐air drying (AD), and the effects of these drying methods on the structures and functional properties of proteins were investigated. The P‐AKP powder dried by SD had the best sensory performance, and its particle size was much smaller than that of FD and AD. Scanning electron microscope displayed a uniform particle size of SD powder and the particles were uniformly dispersed. X‐ray diffraction analysis showed a higher crystallinity of SD sample than AD and FD. Differential scanning calorimeter analysis revealed that SD sample had the best thermal stability and less protein denaturation (Δ H = 210.80 J/g), followed by FD (Δ H = 80.48 J/g) and AD (Δ H = 73.94 J/g; P < 0.05). Fourier transform infrared showed that SD sample contained more protein secondary structure. Compared with SD, the phosphorylated group‐related chemical bonds in FD and AD samples were partially destroyed. SD sample had the highest protein solubility, oil absorption capacity, emulsifying, and foaming activities than FD and AD ( P < 0.05). Although FD had the highest water absorption capacity, sample prepared with AD had the worst functional performance. Therefore, different drying methods used for preparation of the P‐AKP can affect its physicochemical and associated functional properties, and SD could be an appropriate drying method for the industrial mass production of P‐AKP powders with better functionalities. Practical Application The optimal drying method for preparing the phosphorylated Antarctic krill protein (P‐AKP) powder was proved to be spray‐drying (SD), because the physicochemical and functional properties were better for P‐AKP dried by SD than the other drying methods. Hence, SD was recommended for the industrial ...