Gel Properties Of Myofibrillar Protein Research Articles

Effect of starch and peanut oil on physicochemical and gel properties of myofibrillar protein: Amylose content and addition form

Starch and peanut oil (PO) were widely used to improve the gel properties of surimi, however, the impact mechanism of addition forms on the denaturation and aggregation behavior of myofibrillar protein (MP) is not clear. Therefore, the effect of starch, PO, starch/PO mixture, and starch-based emulsion on the physicochemical and gel properties of MP was investigated. The results showed that amylose could accelerate the aggregation of MP, while amylopectin was conducive to the improvement of gel properties. The addition of PO, starch/PO mixture, or starch-based emulsion increased the turbidity, solubility, sulfhydryl content of MP, and improved the gel strength, whiteness, and texture of MP gel. However, compared with starch/PO mixture group, the gel strength of MP with waxy, normal and high amylose corn starch-based emulsion increased by 22.68 %, 10.27 %, and 32.89 %, respectively. The MP containing emulsion had higher storage modulus than MP with starch/PO mixture under the same amylose content. CLSM results indicated that the oil droplets aggregated in PO or starch/PO mixture group, while emulsified oil droplets filled the protein gel network more homogeneously. Therefore, the addition of starch and PO in the form of emulsion could effectively play the filling role to improve the gel properties of MP.

Impact of Flammulina velutipes polysaccharide on properties and structural changes of pork myofibrillar protein during the gel process in the absence or presence of oxidation

The present study aimed to investigate the impact of Flammulina velutipes polysaccharide (FVSP) on the rheological properties and structural alterations of myofibrillar protein (MP) and oxidized MP (OMP), utilizing techniques such as rhehometer, fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). In the unoxidized system, the addition of 5.00% FVSP significantly improved (p < 0.05) the storage and loss moduli of the composite gel and promoted the α-helix to β-sheet transformation. These effects enhanced the protein's gel strength and water-holding capacity (WHC). In the oxidation system, 5.00% FVSP had significant effects (p < 0.05) on repair and improvement of the oxidized MP. These effects inhibited the cross-linking aggregation and degradation of the protein. In addition, the addition of FVSP significantly improved the gel properties of MPs after oxidation (p < 0.05), hindered fracture of the protein gel network structure. In summary, polysaccharides have a substantial effect on the functional characteristics of MP, and FVSP could potentially be applied in meat products.

Inhibition of the interactions of myofibrillar proteins with gallic acid by β-cyclodextrin-metal-organic frameworks improves gel quality under oxidative stress

Generally, high levels of natural phenolic antioxidants, which are needed in meat products to exert equivalent antioxidant effects as synthetic antioxidants, can interact with myofibrillar proteins and cause aggregation of the proteins, giving rise to undesirable deterioration of gel quality. In this study, β-cyclodextrin-metal-organic frameworks (K-β-CD-MOFs) were synthesized based on β-CD and K+ ions using methanol vapor diffusion method, and used to inhibit excessive covalent and non-covalent interactions between gallic acid (GA) and myofibrillar proteins under oxidative stress without degrading the phenolic antioxidant activity. Results of zeta potential, scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and differential scanning calorimetry (DSC) provided evidence for the formation of GA/K-β-CD-MOFs inclusion complexes. From sulfydryl content, surface hydrophobicity, tryptophan fluorescence, turbidity and particle size analyses, the presence of K-β-CD-MOFs dose-dependently prevented the sulfydryl loss, unfolding of the proteins and formation of insoluble aggregates caused by GA (180 μM/g protein). Dynamic rheology, cooking loss, gel strength, water distribution, microstructure and Raman spectrum were further tested to evaluate effects of K-β-CD-MOFs on the qualities of GA-treated myofibrillar protein gel. Results indicated that more proteins were involved in the formation of a more ordered and homogeneous gel structure with higher gel elasticity and strength, more immobilized water and decreased cooking loss. The overall gel properties of myofibrillar proteins were improved. K-β-CD-MOFs ameliorated the instability of protein structure, manifested as increase in β-sheet content and inter-chain hydrogen bonding and decrease in hydrophobic forces (p < 0.05). This paper provides a novel method to increase the loading amount of phenolic antioxidants without jeopardizing the gel quality of meat products.

A novel EGCG-Histidine complex improves gelling and physicochemical properties of porcine myofibrillar proteins: Insight into underlying mechanisms

Herein, an EGCG-Histidine complex is prepared, characterized, and further used to improve gel properties of myofibrillar proteins (MP). Results of FTIR, XRD, UV–Vis spectroscopy showed that histidine is covalently bound to EGCG by Michael addition or Schiff base reaction to form EGCG-Histidine complex, and antioxidant activity of EGCG-Histidine complex is significantly increased compared to EGCG or histidine alone (P < 0.05). The addition of EGCG-Histidine complex results in cooking loss of gel decreasing from 66.7 ± 0.23 % to 40.3 ± 2.02 %, and improves rheological properties of MP, and enhances gel strength from 0.10 ± 0.01 N to 0.22 ± 0.03 N, indicating positive effect of EGCG-Histidine complex on MP gel formation, above results is supported by results of SEM, CD spectroscopy, SDS-PAGE, and tryptophan fluorescence. These results indicated that EGCG-Histidine complex can be used as a functional ingredient to improve gel quality of meat products.

Insight into the Effects of Hydrodynamic Cavitation at Different Ionic Strengths on Physicochemical and Gel Properties of Myofibrillar Protein from Tilapia (Oreochromis niloticus).

Effects of different ionic strengths (0.2, 0.4, and 0.6 mol/L) and different hydrodynamic cavitation (HC) treatment times (0, 1, 2, 3, and 4 min) on the conformation and gel properties of tilapia myofibrillar proteins (TMP) were investigated. The results showed that the solubility of TMP was significantly enhanced (p < 0.05) with the increase in NaCl concentration, and the gel characteristics were significantly improved. After HC treatment of TMP, the average particle size was significantly reduced (p < 0.05) and solubility was significantly enhanced (p < 0.05) with the increase in treatment time, the internal hydrophobic groups and reactive sulfhydryl groups were exposed. The intrinsic fluorescence spectra showed the unfolding of the spatial tertiary structure of proteins, and the circular dichroism spectroscopy showed the significant reduction in the content of α-helix in the secondary structure of the proteins (p < 0.05). In addition, the WHC and gel strength of the TMP heat-induced gels were enhanced, which improved the microstructure of the gels, and scanning electron microscopy showed that the gel network of the TMP gels became denser and more homogeneous. Dynamic rheology results showed that HC treatment resulted in a significant increase in the final G' and G" values of TMP. In conclusion, HC treatment was able to improve the physicochemical structure and gel properties of TMP at different ionic strengths. This study presents a novel processing technique for the quality maintenance aspect of salt-reduced surimi gel products.

Perilla seed oil high internal phase emulsion improve the gel properties of myofibrillar protein

The effects of perilla seed oil high internal phase emulsions stabilized by pea protein (PP-PSO HIPEs) on the gel properties and conformation of myofibrillar protein (MP) gels were investigated. The results showed that the PP-PSO HIPEs with 4.0 % (w/v) PP formed stable HIPEs with low droplet size and good viscoelasticity. The addition of PP-PSO HIPEs (5.0 % − 15.0 %) could significantly improve the MP gel properties (P < 0.05), while the addition of 10.0 % PP-PSO HIPEs showed the highest gel strength and water holding capacity. Otherwise, the MP gels with 10.0 % PP-PSO HIPEs showed higher proportions of immobile water (PT22) and lower proportion of free water (PT23), and the Raman spectra suggested that the content of α-helix decreased, while the content of β-sheet increased (P < 0.05), thus facilitating the formation of better gel properties. Therefore, the addition of PP-PSO HIPEs is a potential alternative for developing fat-reduced meat products.

Paramyosin from field snail (Bellamya quadrata): Structural characteristics and its contribution to enhanced the gel properties of myofibrillar protein

To assess the blending effect of field snails with grass carp muscle, the effects of paramyosin (PM) and actomyosin (AM) with different mixture ratios on the gel properties of the binary blend system were investigated in our work. The purified PM from field snail muscle was about 95 kDa on SDS-PAGE. Its main secondary structure was α-helix, which reached to 97.97 %. When the amount of PM increased in the binary blend system, their rheological indices and gel strength were improved. The water holding capacity (WHC) increased to 86.30 % at a mixture ratio of 2:8. However, the WHC and the area of immobile water (P22) dramatically decreased, and the area of free water (P23) increased when the mixture ratio exceeded 4:6. The low level of PM in binary blend system promoted the formation of a homogenous and dense gel network through non-covalent interactions as observed results of SEM and FTIR. When there were redundant PM molecules, the development of heterostructure via hydrophobic interaction of tail-tail contributed to the reduced gel properties of the binary blend system. These findings provided new insight into the binary blend system of PM and AM with different ratios to change the gel properties of myofibrillar protein.

Effects of calcium chloride on the gelling and digestive characteristics of myofibrillar protein in Litopenaeus vannamei

In this study, the effects of CaCl2 (0, 25, 50, 75, and 100 mM) on the gelling and digestive properties of the myofibrillar protein (MP) in Litopenaeus vannamei were investigated. The results showed that increasing CaCl2 concentration led to changes in the tertiary structure of MP. Specifically, compared with the control group, a 64.31 % increase in surface hydrophobicity and a 45.90 % decrease in the sulfhydryl group were observed after 100 mM CaCl2 treatment. Correspondingly, the water holding capacity and strength of the MP gel increased by 24.46 % and 55.99 %, respectively. These changes were positively correlated with the rheological properties, microstructure pore size, and content of non-flowable water. The mechanical properties of MP gel were improved, and the microstructure became more compact with the increase in CaCl2 concentration. Furthermore, the particle size of the digested MP gels decreased in the presence of CaCl2, which improved the digestion characteristics of MP gels.

Effects and mechanisms of different κ-carrageenan incorporation forms and ionic strength on the physicochemical and gelling properties of myofibrillar protein

The present work was aimed to investigate the effects of incorporating κ-carrageenan into myofibrillar protein (MP) as a dry powder (CP) or water suspension (CW) and the ionic strength (0.3 or 0.6 M sodium chloride (NaCl)) on MP physicochemical and gelling properties. The results indicated that incorporation of either CP or CW significantly increased turbidity, surface hydrophobicity, particle size and rheological behaviour of MP. In contrast, the protein solubility and fluorescence intensity of MP decreased when added with each form of κ-carrageenan (P < 0.05). These observed effects improved MP's gelling properties and produced a more compact and homogenous gel network after heating treatment. Moreover, the addition of CW rendered higher gel strength, water holding capacity and intermolecular interactions, such as ionic, hydrogen and disulphide bonds and hydrophobic interactions in MP gel compared with those added with CP, especially for 0.3 M NaCl (P < 0.05). Furthermore, addition of CW significantly decreased the α-helix content of MP gels (P < 0.05), which mainly contributing to the transformation from a random structure to an organised configuration. In addition, a higher NaCl concentration (0.6 M) enhanced the gelling properties of MP gels compared with 0.3 M NaCl concentration in the presence of each form of κ-carrageenan. Therefore, our present study indicated that incorporation form of κ-carrageenan and ionic strength have distinctive effects on regulating physicochemical characteristics and improves gelling properties of MP.

Study of four polyphenol-Coregonus peled (C. peled) myofibrillar protein interactions on protein structure and gel properties

The effects of four polyphenols—chlorogenic acid (CA), gallic acid (GA), epicatechin gallate (ECG), and epigallocatechin gallate (EGCG) on the structure, gel properties, and interaction mechanisms of myofibrillar protein (MP) were studied. The changes in MP structure with polyphenols were analyzed using circular dichroism. The ultraviolet and fluorescence spectra and thermodynamic analysis indicated that the type of binding between the four polyphenols with the MP was static quenching of complex formation. GA had a more pronounced effect on improving MP gel properties. Finally, molecular docking determined that the affinity of the protein with the four polyphenols was in the order EGCG > ECG > CA > GA, with the main interaction force being hydrophobic interactions and hydrogen bonding, but hydrogen bonding dominates the interaction between GA and the protein. The findings illuminate the mechanism of MP binding to different polyphenols and facilitate the study of polyphenol–protein properties.

Effects of exopolysaccharide by Pediococcus acidilactici S1 on the gelation properties and microstructure of porcine myofibrillar protein

The utilization of extracellular polysaccharides (EPS) derived from lactobacilli is widely observed in the dairy and cereal sectors, whereas their implementation in meat products has received limited research attention. This study was to enhance the utilization of EPS from Pediococcus acidilactici S1 (S1-EPS) in the meat industry and optimize the gel properties of myofibrillar protein (MP)-based food systems. In the study, the impact of incorporating S1-EPS on the properties of MP gels was investigated, revealing significant improvements in water retention, strength, textural characteristics, and rheological behavior. Furthermore, it was observed that S1-EPS facilitated myosin aggregation through hydrophobic interactions and induced a transition in the secondary structure and microstructure of MP from disorder to order. In molecular docking experiments, S1-EPS demonstrated stable binding to myosin through hydrogen bonding and robust electrostatic interactions, indicating its potential as a valuable gelling agent for meat products and contribution to the development of MP gel structure following heat treatment.

Effects of eugenol on the structure and gelling properties of myofibrillar proteins under hydroxyl radical-induced oxidative stress

The effects of eugenol (EG; 0, 5, 20, and 50 mg/g protein) on the structure and gel properties of pork myofibrillar protein (MPs) under a hydroxyl radical-generating system were explored in this study. The results revealed that the addition of a high concentration of EG (50 mg/g protein) markedly reduced the carbonyl content and enhanced the fluorescence intensity, surface hydrophobicity, and protected the secondary structure of MPs, compared to oxidized MPs. In addition, the high concentration group noticeably increased the storage modulus (G′), gel strength, and water-holding capacity (WHC), and significantly hindered the oxidation-induced transformation of immobilized water of the MPs gel to free water and basically favored the formation of a finer and more homogeneous three-dimensional network structure, This work verified that the adding of EG could effectively improve the gel quality of oxidized MPs and more successfully delay oxidation-induced damage to muscle protein structure.

Diacylglycerol emulsion with different droplet size improves the gelation properties of Nemipterus virgatus myofibrillar protein

Effects of diacylglycerol (DAG) emulsions with different particle sizes on gel properties, microstructures and chemical forces of myofibrillar protein (MP) gels were investigated. DAG emulsions addition significantly improved the whiteness of MP gels. With the decrease of emulsion droplet size, G', G“ and immovable water content of MP gels gradually increased, and cooking loss decreased, in which, emulsion prepared under 200 W reduced the cooking loss to the minimum value of 2.57 %. Furthermore, the gel strength and texture properties of MP gels were enhanced as the decreasing emulsion droplet size, and significant improvement (P < 0.05) appeared in gel strength and hardness when ultrasonic power reached 200 W, and then texture indexes tended to be stable as power continued to increase. Reducing the emulsion particle size facilitated the uniform distribution of DAG in the gel network and enhanced the chemical forces of composite gel, forming the more compact network structure.

Effect of Chickpea Dietary Fiber on the Emulsion Gel Properties of Pork Myofibrillar Protein.

In this study, the effect of chickpea dietary fiber (CDF) concentration (0%, 0.4%, 0.8%, 1.2%, 1.6%, and 2.0%) on emulsion gel properties of myofibrillar protein (MP) was investigated. It was found that the emulsifying activity index (EAI) and emulsifying stability index (ESI) of MP increased with the increasing content of CDF. Moreover, the water- and fat-binding capacity (WFB), gel strength, storage modulus (G'), and loss modulus (G") of MP emulsion gel also increased with increasing content of CDF. When the concentration of CDF was 2%, the most significant improvement was observed for EAI, breaking force, and WFB (p < 0.05); the three-dimensional gel network structure of the MP emulsion gel was denser and the pore diameter was smaller. The T21 relaxation time of emulsion gel decreased while the PT21 increased significantly with the increasing content of CDF, suggesting that the emulsion gel with CDF had a better three-dimension network. The addition of CDF led to an increased content of β-sheet and reactive sulfhydryl and increased surface hydrophobicity of MP, thus improving the gel properties of the MP emulsion gel. In conclusion, the addition of CDF improved the functional properties and facilitated the gelation of the MP emulsion, indicating that CDF has the potential to improve the quality of emulsified meat products.

The effect of high-voltage electrostatic field on the interactions between duck myofibrillar protein and inulin: An underlying mechanisms study

This study investigated the effect of high-voltage electrostatic field (HVEF) treatment on the interactions between duck myofibrillar protein (MP) and inulin, as well as explored the gel properties of adding inulin to duck MP. Hence, different inulin content (0–30 mg mL−1) were added to duck MP and HVEF treatment was applied in the gelation process.The results revealed that HVEF combined with the addition of 30 mg mL−1 inulin treatment significantly increased (P < 0.05) the water holding capacity and gel strength by 0.20 and 2.61 times, respectively. Moreover, the rheological characteristics and the formation of the three-dimensional network structure was promoted after added inulin and applied HVEF treatment. The HVEF treatment in modifying MP-inulin interaction promoted the conversion of α-helix to β-sheet, β-turn and random coil, significantly increased (P < 0.05) the content of R–SH groups and surface hydrophobicity, thus revealing the underlying mechanisms of the enhancement of duck MP gel performance. Principal component analysis revealed these interrelationships. This data demonstrated that inulin addition combined with HVEF treatment might be a new and effective strategy to enhance the duck MP gel properties.

Suppression mechanism of L-lysine on the Epigallocatechin-3-gallate-induced loss of myofibrillar protein gelling potential

As a natural antioxidant, Epigallocatechin-3-gallate (EGCG) needed to be added in high doses to maintain the quality of meat products. However, high doses of EGCG caused the excessive aggregation of myofibrillar protein (MP), which damaged the gel properties of MP gels. Therefore, the purpose of this study was to investigate the mitigation of EGCG-induced loss of MP gelling potential by L-Lysine (L-Lys). The results showed that the addition of 20 mM L-Lys induced excessive unfolding and loose aggregation of MP at 10 µmol/g EGCG, and hence, reducing the solubility (14.5%) and the tryptophan fluorescence, and forming a network structure with a large aperture. Therefore, the cooking loss was decreased from 29.20% to 15.13%, and the strength of MP gels was decreased from 0.35 N to 0.17 N. However, L-Lys hindered the hydrogen bonding interactions and hydrophobic interactions between MP and EGCG by competing the binding sites of MP at 50 µmol/g EGCG, which was supported by the Zeta potential, surface hydrophobicity, FTIR and molecular docking analysis. Thus L-Lys mitigated the protein aggregation caused by 50 µmol/g EGCG, improved the solubility (23.02%∼86.99%) and apparent viscosity, which were beneficial for the formation of a continuous network structure in MP gels. Therefore, the cooking loss of MP gels was decreased from 52.40% to 41.30%, and the gel strength was enhanced from 0.13 N to o.22 N with 20 mM L-Lys addition. The present study could provide a new strategy for increasing the amounts of EGCG in meat products without damaging the gel properties of meat products.

Magnetic field-assisted cascade effects of improving the quality of gels-based meat products: A mechanism from myofibrillar protein gelation

Physics-assisted processing technologies have huge potential in the meat processing industry. By modeling two essential procedures (pickling and preheating) of gels-based meat products, this work investigated the cascade effects of a new physical technology (magnetic field) on the conformational structures and gel properties of myofibrillar proteins (MPs). Samples were subjected with four magnetic field (MF)-assisted treatments (group A, both processes without MF; group B, pickling without MF combining with preheating with 4.5 mT MF; group C, pickling with 3.0 mT MF combining with preheating without MF; group D, pickling with 3.0 mT MF combining with preheating with 4.5 mT MF). The result showed that MF-assisted treatments significantly improved water holding capacity (WHC) of MP gels compared with group A (46.9%), reaching the maximum value of 52.1% in group D.According to the low-field nuclear magnetic results, group D decreased the percentages of P22 (6.97%) and increased the percentages of P21 (93%), which showed that water molecules were more tightly bound to each other. Meanwhile, the unfolding of α-helix and the formation of random coil of MF-assisted treatments resulted in more exposure of internal groups, leading to the formation of a dense network. These findings would provide new insights to improve the quality of gels-based meat products via the MF.

Changes in the Quality of Myofibrillar Protein Gel Damaged by High Doses of Epigallocatechin-3-Gallate as Affected by the Addition of Amylopectin.

This work investigated the improvement of amylopectin addition on the quality of myofibrillar proteins (MP) gel damaged by high doses of epigallocatechin-3-gallate (EGCG, 80 μM/g protein). The results found that the addition of amylopectin partially alleviated the unfolding of MP induced by oxidation and EGCG, and enhanced the structural stability of MP. Amylopectin blocked the loss of the free amine group and thiol group, and increased the solubility of MP from 7.0% to 9.5%. The carbonyl analysis demonstrated that amylopectin addition did not weaken the antioxidative capacity of EGCG. It was worth noting that amylopectin significantly improved the gel properties of MP treated with a high dose of EGCG. The cooking loss was reduced from 51.2% to 35.5%, and the gel strength was reduced from 0.41 N to 0.29 N after adding high concentrations of amylopectin (A:E(8:1)). This was due to that amylopectin filled the network of MP gel after absorbing water and changed into a swelling state, and partially reduced interactions between EGCG and oxidized MP. This study indicated that amylopectin could be used to increase the polyphenol loads to provide a more lasting antioxidant effect for meat products and improve the deterioration of gel quality caused by oxidation and high doses of EGCG.

Dose-Dependent Effect of Hyperoside on the Physicochemical and Gel Properties of Porcine Myofibrillar Proteins at Different NaCl Concentrations under Oxidative Stress.

The effects of HYP (10, 50, and 250 μM/g protein) on the physicochemical and gel properties of myofibrillar proteins (MPs) at different NaCl concentrations under oxidative stress were explored. The incorporation of HYP significantly reduced carbonyl content and decreased the loss of free amine groups in a dose-dependent manner, regardless of NaCl concentration. In addition, HYP induced a dose-dependent decrement in total sulfhydryl content regardless of NaCl concentration, which might result from the formation of thiol-quinone adducts via Michael addition. The surface hydrophobicity was significantly increased with HYP addition. Nevertheless, compared with samples treated with 50 μM/g HYP, 250 μM/g HYP caused a significant decrease in surface hydrophobicity, which might be due to the increase in the extent of MPs unfolding and the concomitant aggregation of MPs by hydrophobic interaction. Furthermore, HYP also showed a dose-dependent increment in the water-holding capacity (WHC) and gel strength of MPs gels, which might be due to more orderly crosslinks via fibrous filaments at 0.2 M NaCl and more regular and lamellar structures with smaller and more homogeneous pores at 0.6 M NaCl. In summary, HYP reduced the oxidation-mediated changes of physicochemical characteristics, preventing the oxidative damage of MPs and reinforcing the ordered crosslinks of MPs-MPs and MPs-HYP during thermal gelation, ultimately resulting in a better gel quality. These results provide a theoretical support for the practical application of HYP as a natural antioxidant in gel-type meat products.

Effect of Artemisia sphaerocephala Krasch gum on the gel properties of myofibrillar protein and its application in cooked sheep sausage

Artemisia is widely distributed in desert areas northern China. Its seeds are rich in water-insoluble gelatin Artemisia sphaerocephala Krasch gum (ASKG) and frequently utilized for various types of pasta making. This study aims at wider utilization of the ASKG in food industry and to improve the gel properties of the myofibrillar protein-based food system containing starch. Firstly, the influence of ASKG on pasting and retrogradation of potato starch (PS) was discussed. Also, the rheological properties, emulsification properties, microstructure, protein conformation, and textural properties of sheep meat myofibrillar protein (SMP)/ASKG and SMP-potato starch (PS)/ASKG composites were investigated. Besides, the sensory quality and texture of cooked sheep sausage were evaluated to explore the application of ASKG in real complex food system. The stronger hydrophobic interaction of protein and H-bonding formed between components, which may be attributed to transition of α-helix to β-conformation of the protein. The ASKG additive promoted the formation of a more compact and uniform gel network of composites, leading an increase of the water holding capacity (WHC), gel strength and springiness and emulsion stability of SMP composites. The SMP-PS/ASKG-0.5% composites kept the highest WHC about 66.5%, gel strength about 70.57 g, springiness about 0.73 g. Furthermore, ASKG has a retardation effect on the retrogradation of PS. ASKG could delay the water loss and the increase of hardness of sausage during five-day storage, suggesting a visible satisfactory capability of the ASKG to improve the gel texture and storage quality of cooked sheep sausage.