Physicochemical properties and action mechanism of chicken lung protein hydrolysate modified by plastein reaction

Abstract

Plastein reaction is the process of colloid formed from concentrated hydrolysate by protease under suitable conditions, but the underlying mechanism has not been clarified. This study examined the functional and mechanistic changes in chicken lung protein hydrolysate (CLPH) caused by the plastein reaction. The results revealed that the plastein reaction products stretched, the hydrophobic groups were exposed, and the reaggregation occurred. In terms of function, solubility declined after modification, but foaming properties and emulsification properties increased. Moreover, the elevated Fe²⁺ chelation (from 18.20 % to 48.32 %), DPPH (30.04 %–71.74 %), ABTS (41.66 %–62.44 %) and hydroxyl radical (34.85 %–63.22 %) scavenging power suggested that the plastein strengthened the CLPH in a broader sense. Meanwhile, hydrogen bonds and hydrophobic interactions were crucial in creating the structure of the plastein modification products. In summary, the plastein reaction is a viable method for influencing structural changes to enhance protein function.