Solubilization mechanism and structural properties of high‐denatured peanut protein treated by shearing

Abstract

High-denatured peanut protein (PP), which exhibited a surface structure dominated by hydrophobic groups due to the high temperature and pressure in oil extraction, was limited in application with poor hydration property. To improve the interaction between PP and water molecules, high-speed shearing homogenization (HSH) technique was used to depolymerize the aggregates. The results showed that the concentration of soluble protein was increased from 0.22 to 0.79 mg/mL at 15 min, followed by enhanced water holding ability, decreased particle size, and thermal stability. Otherwise, the decrease of α-helix structure and the exposure of chromophoric groups indicated that the secondary and tertiary structure were unfolded. The stretching vibration of C-O, C=O, C-H, the increase of β-turn structure, and the exposure of hydrophilic groups (-OH) were the main reason for the improved hydration property. Furthermore, the increased hydration property facilitated the formation of a stable emulsion via stabilizing the water phase. The enhanced hydration property of PP contributed to extending its application in the preparation of beverages and delivery products such as Pickering emulsion and gel for drugs. Practical applicationsAs one of the non-thermal processing technologies, HSH technology has been widely used in the field of food processing. HSH treatment depolymerized the materials via producing strong shear force, vortex, and cavitation, which was easy to operate and avoided pollution. This study used the HSH technology to improve the hydration property of PP, which has great research potential for the preparation of drug delivery carriers, nutritional products, tissue scaffolds, and food packaging materials. | INTRODUCTIONMost peanuts grown in China are mainly used for producing oil. The defatted peanut powder is a protein-rich, inexpensive, and underutilized by-product, which contains 50-55% peanut protein (PP; Beuchat, Cherry, & Quinn, 1975). Arachin and conarachin are the main protein components. However, PP, in defatted peanut powder, is highly denatured in the process of high temperature pressing, forming an external structure dominated by hydrophobic groups, which affects the structural, functional properties, and some biological activities, especially in poor solubility and emulsification (Silveira et al., 2019).The optimization of the hydration property in denatured PPs has great application prospects in the preparation of drug delivery carriers, nutritional products, tissue scaffolds, and food packaging materials,

Surface modification of peanut meal with atmospheric cold plasma: Identifying the critical factors that affect functionality

“…The contents of β-sheet and β-turn in ACP-treated PM were increased and then decreased, respectively, which indicated that ACP induced the rearrangement of β-structure and the formation of hydrogen bonds. These results were in agreement with the analysis of Yu et al (2022b). Meanwhile, the decrease of α-helix was attributed to its transformation to the β-sheet after ACP treatment.…”

“…These reactions led to the rupture of hydrophobic bonds in proteins and the exposure of active sites in the protein core. Meanwhile, some hydrophilic groups were generated and bound to the PM surface, thereby allowing more water molecules to penetrate the core (Yu et al ., 2021b). Ekezie et al .…”

“…The trend of WHC was similar to that of soluble protein concentration, which indicated that the dissolution behaviour of modified peanut protein played an important role in the WHC of PM. Otherwise, prolonged ACP exposure duration could lead to the aggregation effect between protein molecules due to excessive oxidation (Yu et al ., 2021b).…”

“…These results were in agreement with the analysis of Yu et al . (2022b). Meanwhile, the decrease of α‐helix was attributed to its transformation to the β‐sheet after ACP treatment.…”