Aug 2026· Journal of texture studies· Vol 57· 0 citations· 78 references
Medicine
Abstract
In this study, we evaluated how varying concentrations of two exogenous proteins, egg white protein (EWP) and whey protein isolate (WPI) influence heat‐induced aggregation and gelation of cod myofibrillar proteins (MPs). Addition of exogenous proteins enhanced the MP solubility and surface hydrophobicity while reducing the turbidity and total sulfhydryl levels. These physicochemical changes occurred during heating in three kinetic phases, an initial rapid phase (0–30 min), a slower transitional phase (30–60 min), and a second rapid aggregation phase (70–90 min) until equilibrium was reached. Dynamic rheology revealed that EWP enhanced G′ at moderate concentrations but reduced it at higher levels, while WPI caused a progressive decline in G′ with increasing concentration. Gel property analysis showed that EWP‐M (MP:EWP = 2:14) produced the highest gel strength, whereas WPI‐L (MP:WPI = 1:15) resulted in the lowest cooking loss and highest water‐holding capacity (WHC). WPI‐containing systems exhibited slightly lower gel strength but showed improved water retention and a uniform microstructure. Notably, a 1:1 EWP‐WPI combination showed synergistic network solubility, hydrophobic exposure, and uniform microstructure, leading to high gel strength with minimal cooking loss and maximum WHC. Mechanistically, EWP acted as a structural enhancer, promoting gel network strengthening and increased rigidity, whereas WPI functioned primarily as a filler, enhancing water retention and reducing structural heterogeneity. These findings offer key insights into MP/EWP‐WPI interactions and support the optimization of composite protein gel systems.
The effects and mechanisms of methylcellulose (MC), carboxymethylcellulose (CMC), hydroxypropyl methylcellulose (HPMC), and microcrystalline cellulose (MCC) on myofibrillar protein (MP) gelation at 0.3 M NaCl were investigated. Results showed that all celluloses enhanced the hardness, springiness, and water-holding capacity of low salt MP gel in a dose-dependent manner. Specifically, MC and HPMC reached optimal performance at 0.9% concentration, whereas CMC and MCC reached their peak at 0.3% addition. In particular, 0.9% MC addition gave the low-salt MP gel its highest hardness (502.98 g), water-holding capacity (98.7%), and storage modulus (3388 Pa), surpassing the normal-salt control. MC increased MP surface hydrophobicity from 58.9 to 86.1, facilitated disulfide and non-disulfide covalent cross-linking of myosin heavy chain intensity, and formed the densest gel microstructure. HPMC most strongly promoted low salt MP disulfide bond formation and achieved a water-holding capacity of 96.8%. However, its thermally reversible network partly dissociated upon cooling, limiting the storage modulus to 1656 Pa. CMC addition increased the absolute zeta potential from 17.4 mV to 34-37 mV via its carboxymethyl groups, generating electrostatic repulsion that impeded MP aggregation and led to a weak gel with high immobilized water but low water-holding capacity (86.8%). MCC behaved as an inert filler, yielding only marginal improvements. In conclusion, low-salt MP gel with MC addition surpassed normal-salt levels through hydrophobicity-driven unfolding and network reinforcement, with HPMC addition reaching normal-salt levels by enhancing disulfide bond formation, while the benefits of CMC and MCC additions were limited by electrostatic repulsion and inert filling.
Zhi Huang, Can Deng, Xi Cao et al.· Food Research International· 0 citations
As a green non-thermal technology, plasma-activated water (PAW) generates reactive oxygen and nitrogen species (RONS) through plasma-liquid interactions and thereby affects the oxidation, conformation, and functionality of aquatic myofibrillar proteins (MPs). To investigate the regulatory effects of PAW on yellow croaker MPs, the original extraction buffer was replaced with plasma-activated buffer of different activation times, and the oxidation, conformation, and functional changes of MPs during chilled storage were evaluated. The results indicate that moderate PAW treatment induces mild oxidation and modulates protein conformation. PAW-30 s showed a lower bromophenol blue binding capacity (31.55 ± 0.95 μg), indicating limited intermolecular interactions and moderate aggregation that partially masked hydrophobic groups and improved structural stability. As the treatment time was extended to 60 s and 120 s, PAW further promoted the oxidation of thiol groups, altered surface hydrophobicity and intrinsic fluorescence characteristics, and enhanced the conformational rearrangement and intermolecular cross-linking of MP. SDS-PAGE results showed that the effects of PAW were primarily concentrated on the myosin heavy chain (MHC), as shown by MHC band weakening and increased high-molecular-weight aggregates, without obvious low-molecular-weight degradation. Molecular docking analysis further indicated that representative reactive oxygen species in PAW, H₂O₂ and O₃ can bind to specific regions on the MHC surface, thereby inducing local microenvironmental disturbances and oxidative modifications. Overall, PAW regulated yellow croaker MPs mainly through mild oxidation-induced conformational rearrangement and intermolecular cross-linking rather than extensive chain cleavage, with moderate activation being more favorable for maintaining MP structural stability and functional properties.
Fangqi Yuan, Quanyou Guo, Zuofeng Shi et al.· Food Research International· 0 citations
Milk protein concentrate (MPC) is widely used in high-protein foods. However, increasing protein content often leads to undesirable functional and sensory attributes in the finished products. Interactions between whey proteins and caseins during heat treatment play a critical role in determining the structure and functionality of high-protein systems. In this study, a modified MPC containing caseins and preaggregated whey proteins was evaluated for its impact on acid-induced gelation. A model MPC was prepared by blending micellar casein concentrate (MCC) and milk whey protein isolate (mWPI) to achieve an 80:20 casein-to-whey ratio and was considered as the control MPC. Preaggregated whey proteins were produced by heating mWPI at pH 3.0 or pH 7.0 under constant shear, followed by adjusting the pH back to 6.8 and subsequently blending it with MCC. Heating mWPI at pH 7.0 resulted in significantly larger pre-aggregates (87.48 ± 3.22 nm) than heating at pH 3.0 (74.36 ± 1.33 nm; P < 0.05). After readjustment to pH 6.8, samples heated at pH 3.0 exhibited significantly higher viscosity (13.28 ± 0.98 mPa·s) and larger mean particle size (1580.34 ± 25.30 nm) compared with those heated at pH 7.0 (7.52 ± 0.53 mPa·s; 99.4 ± 9.86 nm). During acid-induced gelation, modified MPC containing whey proteins preaggregated at pH 3.0 showed a longer gelation time (25 min) and lower maximum storage modulus (1394.35 ± 62.15 Pa) compared with samples containing pre-aggregates formed at pH 7.0 (9 min; 2117.08 ± 15.59 Pa). These results demonstrate that pre-aggregation conditions of whey proteins strongly influence casein-whey interactions, viscosity, and gelation behavior. The new ingredients can potentially help in the development of a wide range of high-protein products, such as low viscosity drinkable yogurt, yogurt with reduced graininess. Overall, modified MPC containing preaggregated whey proteins shows potential as a functional ingredient for tailoring the rheological and structural properties of high-protein dairy systems.
Abrielle Schnurr, Suchismita Roy, J. Amamcharla· Journal of Dairy Science· 0 citations
This study evaluated the effects of low-frequency alternating magnetic field (AMF) on mass transfer, myofibrillar protein (MP) structure, and quality of beef during marination. AMF significantly enhanced NaCl and moisture diffusion, reducing marination time by over 50%. The improvement was linked to AMF-induced MP conformational unfolding, increased surface hydrophobicity, reduced solubility, and promoted protein aggregation via strengthened hydrophobic interactions. Unlike conventional treatments, AMF-driven aggregation widened inter-myofibrillar spaces, facilitating ion and water migration. Additionally, AMF reduced cooking loss while maintaining shear force and texture, indicating improved water-holding capacity without compromising tenderness. These effects were attributed to microstructural remodeling that preserved myofibrillar integrity. Overall, AMF-assisted marination enhances processing efficiency and technological quality, representing a promising non-thermal strategy for meat processing.
Lixin Du, Qihan Liu, Guanghong Zhou et al.· Food Chemistry· 0 citations
Dysphagia-adapted fluidized meat products alter the protein matrix structure and may impair digestibility. This work evaluated the digestive and nutritional properties of carboxymethyl cellulose (CMC)-modified myofibrillar protein (MP) thickened fluids across three matrices: liquid solution (MP), semisolid state (MP/CMC), and solid gel (MPgel). In vitro digestion indicated all MP matrices exhibited lower digestibility under elderly digestive conditions than adult systems, especially during gastric stage. CMC promoted protein hydrolysis by enhancing the accessibility of MP to pepsin. Digestive kinetics implied that initial and maximal gastric digestion rates of MP/CMC for adults were 13.07- and 3.65-fold higher than those of liquid MP, while dense cross-linked networks reduced digestion extent and rates in MP gel. In vivo, CMC thickening slowed gastrointestinal transit of semisolid MP, sustaining abundant gastric peptides and maintaining high steady-state serum total amino acids in mice. This work provided fundamental insights into the digestive and nutritional characteristics of CMC-induced meat protein-based fluids.
Jiale Chai, Jingjie Wang, Yue Wang et al.· Journal of Agricultural and...· 0 citations