RESUMEN
The storage and processing of Litopenaeus vannamei are often challenged by the freeze-thaw (F-T) cycle phenomenon. This study delved into the influence of pretreatment with l-arginine (Arg) and l-lysine (Lys) on the myofibrillar proteins oxidation and quality of shrimp subjected to F-T cycles. Arg and Lys pretreatment notably improved water-holding capacity (WHC), textural integrity as well as the myofibrillar structure of the shrimps. A lesser reduction in the amounts of immobile and bound water was found in the amino acid-treated groups, and the oxidation of lipids and proteins were both decelerated. Molecular simulation results indicated that Arg and Lys could form hydrogen and salt-bridge bonds with myosin, enhancing the stability of Litopenaeus vannamei. The study concludes that Arg and Lys are effective in alleviating the adverse effects of F-T cycles on the quality of Litopenaeus vannamei, and provides a new solution for the quality maintenance during storage and processing.
Asunto(s)
Arginina , Lisina , Proteínas Musculares , Oxidación-Reducción , Penaeidae , Animales , Penaeidae/química , Arginina/química , Lisina/química , Proteínas Musculares/química , Congelación , Conservación de Alimentos/métodos , Mariscos/análisis , Miofibrillas/químicaRESUMEN
To investigate the combination effect of sodium chloride and phosphates on chicken breast myofibrillar proteins, MP gels containing various molarity of NaCl (0.15, 0.30 and 0.45 M) and phosphate (0 and 0.05 M) were prepared, their rheological properties were characterized, and applied to an in vitro digestion model. MP mixture containing 0.45 M NaCl and 0.05 M phosphate had the highest viscosity. The gel strength and cooking yield of MP gels was improved by increasing of molarity of NaCl. As NaCl concentration in MP increased, sulfhydryl levels decreased, while disulfide levels increased. As NaCl and phosphate levels increase, MP gels become denser and porosity decreases, which may reduce protein digestibility. In SDS-PAGE, protein bands from MP gels containing low NaCl levels (≤ 0.30 M) degraded more rapidly during in vitro digestion. These results may support the need for the meat industry to develop low-salt meat products with improved digestibility. KEYWORDS: Chicken, Myofibrillar protein, NaCl, Phosphate, Rheological properties, In vitro digestion.
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Pollos , Digestión , Geles , Proteínas Musculares , Miofibrillas , Fosfatos , Cloruro de Sodio , Animales , Cloruro de Sodio/química , Geles/química , Fosfatos/química , Miofibrillas/química , Miofibrillas/metabolismo , Proteínas Musculares/química , Proteínas Musculares/metabolismo , Reología , Modelos Biológicos , Carne/análisis , ViscosidadRESUMEN
This study primarily investigated the improvement of high-dose Epigallocatechin-3-Gallate (EGCG)-induced deterioration of MP gel by soy protein isolate (SPI) addition. The results showed that EGCG could interact with MP, SPI, and HSPI (heated), indicating the competitive ability of SPI/HSPI against EGCG with MP. EGCG was encapsulated by SPI/HSPI with high encapsulation efficiency and antioxidation, with antioxidant activities of 78.5% â¼ 79.2%. FTIR and molecular docking results revealed that MP, SPI, and HSPI interacted with EGCG through hydrogen bonding and hydrophobic interactions. SPI/HSPI competed with MP for EGCG, leading to the restoration of MHC and Actin bands, alleviating the aggregation caused by EGCG and oxidation. Additionally, SPI/HSPI-E significantly reduced the high cooking loss (23.71 and 26.65%) and gel strength (13.60 and 17.02%) induced by EGCG. Hence, SPI competed with MP for EGCG binding site to ameliorate MP gel properties, thereby alleviating the detrimental changes in MP caused by high-dose EGCG and oxidation.
Asunto(s)
Catequina , Geles , Simulación del Acoplamiento Molecular , Proteínas de Soja , Catequina/química , Catequina/análogos & derivados , Catequina/metabolismo , Catequina/farmacología , Proteínas de Soja/química , Proteínas de Soja/metabolismo , Geles/química , Antioxidantes/química , Antioxidantes/farmacología , Interacciones Hidrofóbicas e Hidrofílicas , Animales , Proteínas Musculares/química , Proteínas Musculares/metabolismo , Culinaria , Unión ProteicaRESUMEN
The inhibition of amino acids on the formation of protein-bound HAs was assessed in both model systems and roast beef patties, and the synergism between these amino acids was also investigated. The amino acids can promote the formation of protein-bound HAs at low addition amount, and the total content of protein-bound HAs increased from 444.05 ± 4.98 ng/g of the control group to 517.36 ± 16.51 ng/g when 0.05 % cysteine was added. Amino acid combinations exhibited stable inhibitory effects, with the maximum inhibitory rate of 64 % in the treatment with histidine-proline combination (1:4). The synergistic inhibition may be caused by simultaneously scavenging intermediates and competing for the binding sites of muscle proteins, and the reaction with protein-bound HAs to form adduct can serve as supporting factors to co-mitigate the promotion in protein-bound HAs from increased protein solubility. These findings proposed the potential mitigation strategies against protein-bound HAs formation.
Asunto(s)
Aminas , Aminoácidos , Animales , Bovinos , Aminoácidos/química , Aminoácidos/metabolismo , Aminas/química , Aminas/metabolismo , Proteínas Musculares/química , Proteínas Musculares/metabolismo , Miofibrillas/química , Miofibrillas/metabolismo , Compuestos Heterocíclicos/química , Compuestos Heterocíclicos/farmacología , Retículo Sarcoplasmático/metabolismo , Retículo Sarcoplasmático/químicaRESUMEN
This study investigated the effects of pea protein pre-emulsions containing triglyceride- or diglyceride-oil on the emulsifying and gelling properties of low-salt myofibrillar protein (MP). Pea protein isolates treated with pH12-shifting (PPIpH) or ultrasonication (PPIU) demonstrated superior initial interfacial adsorption and higher final interfacial pressure than native pea protein. Within MP/PPI blends, an increased ratio of MP led to a decrease in interfacial pressure, while simultaneously enhancing film elasticity at both polar and non-polar interfaces. Polar diglyceride promoted protein adsorption and fostered interfacial interactions between modified pea proteins and MP, enhancing the cross-linking of transglutaminase (TG) in the composite emulsion gels. Combining diglyceride-type PPIU and PPIpH emulsions with TG increased gel strength to 0.58 N and 0.63 N, respectively, from an initial 0.33 N, yielding a denser protein network with uniformly dispersed oil droplets. Therefore, the utilization of diglyceride and modified PPI can serve as structural enhancers in comminuted meat products.
Asunto(s)
Emulsiones , Geles , Proteínas de Guisantes , Emulsiones/química , Geles/química , Proteínas de Guisantes/química , Miofibrillas/química , Proteínas Musculares/química , Animales , Pisum sativum/química , Productos de la Carne/análisisRESUMEN
Protein glutaminase (PG; EC 3.5.1.44) is a class of food-grade enzyme with the potential to significantly improve protein functionality. However, its low catalytic activity and stability greatly hindered industrial application. In this study, we employed structural-based engineering and computational-aided design strategies to target the engineering of protein glutaminase PG5, which led to the development of a combinatorial mutant, MT8, exhibiting a specific activity of 31.1 U/mg and a half-life of 216.2 min at 55 °C. The results indicated that the flexible region in MT8 shifted from the C-terminus to the N-terminus, with increased N-terminal flexibility positively correlating with its catalytic activity. Additionally, MT8 notably boosted fish myofibrillar proteins (MPs) solubility under the absence of NaCl conditions and enhanced their foaming and emulsifying properties. Key residues like Asp31, Ser72, Asn121, Asp471, and Glu485 were crucial for maintaining PG5-myosin interaction, with Ser72 and Asn121 making significant energy contributions.
Asunto(s)
Proteínas de Peces , Peces , Glutaminasa , Ingeniería de Proteínas , Glutaminasa/química , Glutaminasa/metabolismo , Glutaminasa/genética , Animales , Proteínas de Peces/química , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Peces/genética , Miofibrillas/química , Miofibrillas/metabolismo , Miofibrillas/enzimología , Proteínas Musculares/química , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Estabilidad de EnzimasRESUMEN
This study investigated the effects of sodium pyrophosphate (SPP) and catechin (C) on the in vitro enzymatic digestion of oxidatively damaged myofibrillar protein (MP) gel. The results indicated that SPP increased the ß-sheet content and the gastric digestibility of the MP gel, while C hindered the transition from α-helix to ß-sheet structure, leading to decreased digestibility. Notably, neither compound significantly affected intestinal digestibility. Furthermore, SPP and C significantly enhanced the antioxidant activity of MP gel digestion products. Notably, their synergistic hydrolysis products, simulating both gastric and gastrointestinal stages, chelated 91.4 % and 89.1 % of Fe2+ and scavenged 59.4 % and 77.6 % of hydroxyl radicals, respectively. Moreover, the final digestion products of the MP gel treated with SPP and C exhibited the highest content of negatively charged amino acids and absolute Zeta potential values. Overall, this study demonstrated that incorporating SPP and C could positively impact the digestion of oxidatively damaged MP gels.
Asunto(s)
Catequina , Digestión , Difosfatos , Geles , Hidrólisis , Difosfatos/química , Difosfatos/metabolismo , Catequina/química , Catequina/metabolismo , Geles/química , Animales , Oxidación-Reducción , Proteínas Musculares/química , Proteínas Musculares/metabolismo , Miofibrillas/química , Miofibrillas/metabolismo , Antioxidantes/químicaRESUMEN
The large yellow croaker roe phospholipids (LYPLs), rich in polyunsaturated fatty acids, is a potential phospholipid additive for meat products. In this work, the effects of LYPLs on the structural and functional properties of myofibrillar protein (MP) were determined, and compared with egg yolk phospholipids (EYPLs) and soybean phospholipids (SBPLs). The results revealed that LYPLs, similar to SBPLs and EYPLs, induced a transformation in the secondary structure of MP from α-helix to ß-sheets and random coils, while also inhibited the formation of carbonyl and disulfide bonds within MP. All three phospholipids induced MP tertiary structure unfolding, with the greatest degree of unfolding observed in MP containing LYPLs. The MP with LYPLs had the highest surface hydrophobicity, emulsification properties and gel strength. In addition, MP with LYPLs added also demonstrated superior rheological properties and water-holding capacity compared with SBPLs and EYPLs. In conclusion, adding LYPLs endowed MP with improved functional properties.
Asunto(s)
Perciformes , Fosfolípidos , Animales , Fosfolípidos/química , Porcinos , Proteínas Musculares/química , Interacciones Hidrofóbicas e Hidrofílicas , Proteínas de Peces/química , Conformación Proteica , Miofibrillas/química , Reología , Estructura Secundaria de ProteínaRESUMEN
In the process of utilizing black soldier fly larvae (BSFL) lipids to develop biodiesel, many by-products will be produced, especially the underutilized protein components. These proteins can be recycled through appropriate treatment and technology, such as the preparation of feed, biofertilizers or other kinds of bio-products, so as to achieve the efficient use of resources and reduce the generation of waste. Myofibrillar protein (MP), as the most important component of protein, is highly susceptible to environmental influences, leading to oxidation and deterioration, which ultimately affects the overall performance of the protein and product quality. For it to be high-quality and fully exploited, in this study, black soldier fly myofibrillar protein (BMP) was extracted and primarily subjected to ultrasonic treatment to investigate the impact of varying ultrasonic powers (300, 500, 700, 900 W) on the structure and functional properties of BMP. The results indicated that as ultrasonic power increased, the sulfhydryl content and turbidity of BMP decreased, leading to a notable improvement in the stability of the protein emulsion system. SEM images corroborated the changes in the microstructure of BMP. Moreover, the enhancement of ultrasound power induced modifications in the intrinsic fluorescence spectra and FTIR spectra of BMP. Additionally, ultrasonic treatment resulted in an increase in carbonyl content and emulsifying activity of BMP, with both peaking at 500 W. It was noteworthy that BMP treated with ultrasound exhibited stronger digestibility compared to the untreated. In summary, 500 W was determined as the optimal ultrasound parameter for this study. Overall, ultrasound modification of insect MPs emerges as a dependable technique capable of altering the structure and functionality of BMP.
Asunto(s)
Proteínas Musculares , Animales , Proteínas Musculares/química , Proteínas Musculares/metabolismo , Proteínas de Insectos/química , Miofibrillas/química , Miofibrillas/metabolismo , Ondas Ultrasónicas , Simuliidae/química , Dípteros/química , Sonicación/métodosRESUMEN
Human Hippo signaling pathway is an evolutionarily conserved regulator network that controls organ development and has been implicated in various cancers. Transcriptional enhanced associate domain-4 (TEAD4) is the final nuclear effector of Hippo pathway, which is activated by Yes-associated protein (YAP) through binding to two separated YAP regions of α1-helix and Ω-loop. Previous efforts have all been addressed on deriving peptide inhibitors from the YAP to target TEAD4. Instead, we herein attempted to rationally design a so-called 'YAP helixα1-trap' based on the TEAD4 to target YAP by using dynamics simulation and energetics analysis as well as experimental assays at molecular and cellular levels. The trap represents a native double-stranded helical hairpin covering a specific YAP-binding site on TEAD4 surface, which is expected to form a three-helix bundle with the α1-helical region of YAP, thus competitively disrupting TEAD4-YAP interaction. The hairpin was further stapled by a disulfide bridge across its two helical arms. Circular dichroism characterized that the stapling can effectively constrain the trap into a native-like structured conformation in free state, thus largely minimizing the entropy penalty upon its binding to YAP. Affinity assays revealed that the stapling can considerably improve the trap binding potency to YAP α1-helix by up to 8.5-fold at molecular level, which also exhibited a good tumor-suppressing effect at cellular level if fused with TAT cell permeation sequence. In this respect, it is considered that the YAP helixα1-trap-mediated blockade of Hippo pathway may be a new and promising therapeutic strategy against cancers.
Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Antineoplásicos , Proteínas de Unión al ADN , Simulación de Dinámica Molecular , Proteínas Musculares , Factores de Transcripción de Dominio TEA , Factores de Transcripción , Proteínas Señalizadoras YAP , Factores de Transcripción/química , Factores de Transcripción/metabolismo , Factores de Transcripción/antagonistas & inhibidores , Humanos , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/química , Proteínas Musculares/química , Proteínas Musculares/metabolismo , Proteínas Adaptadoras Transductoras de Señales/química , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Disulfuros/química , Disulfuros/farmacología , Unión Proteica , Sitios de Unión , Línea Celular Tumoral , Diseño Asistido por Computadora , Diseño de FármacosRESUMEN
Protein hydrolysates derived from aquaculture by-products hold significant promise as key components in the formulation of active films. In our study, we investigated the impact of different protein hydrolysates levels (0.4%, 0.8%, and 1.2%) obtained from the cutting by-product of Serra Spanish mackerel on the mechanical (PHSSM), morphological, optical, thermal, and antioxidant properties, as well as the degradability of biodegradable films. Four treatments were produced, varying the concentrations of PHSSM: C (control, without PHSSM), T4 (with 0.4% PHSSM), T8 (with 0.8% PHSSM), and T12 (with 1.2% PHSSM). These films were based on myofibrillar proteins from fish by-products and pectin extracted from yellow passion fruit. The incorporation of PHSSM led to enhanced barrier properties, resulting in a proportional reduction in water vapor permeability compared to the control film. However, high PHSSM levels (>0.8%) compromised film homogeneity and increased fracture susceptibility. Tensile strength remained unaffected (p > 0.05). PHSSM-enriched films exhibited reduced transparency and lightness, regardless of PHSSM concentration. The addition of PHSSM imparted a darker, reddish-yellow hue to the films, indicative of heightened visible light barrier properties. Moreover, increased PHSSM content (0.8% and 1.2%) appeared to accelerate film degradation in soil. Fourier transform infrared spectroscopy confirmed the presence of pectin-protein complexes in the films, with no discernible differences among the treated samples in the spectra. Incorporating PHSSM also enhanced film crystallinity and thermal resistance. Furthermore, an improvement in the antioxidant activity of the films was observed with PHSSM addition, dependent on concentration. The T8 emerged as the promising candidate for developing active primary packaging suitable for oxidation-sensitive foods.
Asunto(s)
Embalaje de Alimentos , Hidrolisados de Proteína , Embalaje de Alimentos/instrumentación , Hidrolisados de Proteína/química , Animales , Perciformes/metabolismo , Resistencia a la Tracción , Proteínas de Peces/química , Antioxidantes/química , Permeabilidad , Miofibrillas/química , Proteínas Musculares/químicaRESUMEN
The quality of surimi, widely used in processed seafood, is compromised by freeze-thaw cycles, leading to protein denaturation and oxidative degradation. The objective of this study is to explore the effects of adding natural whey peptide hydrolysate (WPH) on the myofibrillar proteins of repeatedly freeze-thawed surimi. Results indicated surimi treated with 15% WPH exhibited only a 128% increase in surface hydrophobicity and a maximum peroxide value of 7.84 µg/kg, significantly lower than the control group. Additionally, salt-soluble protein content, emulsification activity, and stability decreased with the increase in freeze-thaw cycles. With a 15% WPH offering the most significant protective effect, evidenced by reductions of only 25.02%, 42.52% and 37.02% in salt-soluble protein content, emulsification activity, and stability, respectively. These outcomes demonstrate that WPH effectively reduces protein denaturation during repeated freeze-thaw processes. Future research should explore the molecular mechanisms underlying WPH's protective effects and evaluate their applicability in other food systems.
Asunto(s)
Congelación , Hidrolisados de Proteína , Proteína de Suero de Leche , Proteína de Suero de Leche/química , Hidrolisados de Proteína/química , Animales , Productos Pesqueros/análisis , Proteínas Musculares/química , Proteínas de Peces/química , Proteínas Anticongelantes/química , Interacciones Hidrofóbicas e Hidrofílicas , Manipulación de AlimentosRESUMEN
Soy isolate protein / chitooligosaccharide (SPI/COS) glycosylated conjugates was prepared and employed as an emulsifier to stabilize carvacrol-loaded nanoemulsions (CNE-SPI/COS). The effects of CNE-SPI/COS on the oxidation and aggregation of myofibrillar protein (MPs) from sea bass (Lateolabrax maculatus) were investigated. Samples were immersed in sterile water (CK), SPI/COS solution and CNE-SPI/COS solution, respectively, follow by a 15-day refrigerated storage. MPs were extracted from fish fillets at 3-day intervals, then assessed for the oxidation degree and conformational changes in MPs, as well as structural variations in myofibrils. Compared with the CK group, the results obtained from protein oxidation assessment clarified that the oxidation and aggregation of MPs was significantly reduced by the CNE-SPI/COS treatment, as evidenced by the higher total sulfhydryl content and Ca2+-ATPase activity and lower surface hydrophobicity. Conformational analysis of MPs showed that CNE-SPI/COS was effective in maintaining the ordered secondary structure of MPs and reducing the exposure of hydrophobic residues in the hydrophobic core of the tertiary structure. In addition, CNE-SPI/COS was found to be effective in protecting the microstructure of muscle fibers and myofibrils in fish fillets. These results suggest that CNE-SPI/COS can be a promising method to prevent protein oxidation and aggregation in fish.
Asunto(s)
Lubina , Cimenos , Emulsiones , Proteínas de Peces , Oxidación-Reducción , Proteínas de Soja , Animales , Lubina/metabolismo , Emulsiones/química , Cimenos/química , Cimenos/farmacología , Proteínas de Peces/química , Proteínas de Soja/química , Proteínas de Soja/metabolismo , Proteínas Musculares/química , Proteínas Musculares/metabolismo , Oligosacáridos/química , Quitosano/química , Quitina/química , Quitina/análogos & derivados , Miofibrillas/química , Miofibrillas/metabolismo , Alimentos Marinos/análisis , Conservación de Alimentos , Conformación Proteica , RefrigeraciónRESUMEN
The aim of this study was to investigate the distribution pattern and migration pathway of sodium ion in the myofibrillar protein (MP) gel matrix during microwave heating. The results showed that the content of sodium ions in the outer layer of MP gel increased by 47.85% compared with that in the inner layer. In the inner layer of protein gel, the non-covalent disulfide bonds (mainly ε(γ-Glu)-Lys) increased (P < 0.05), which contributed to the formation of a better rigid structure of the protein. The free water content was significantly higher than that of the inner layer (P < 0.05), which was related to the higher mobility of sodium ions. The results of microstructure analysis showed that the outer layer of the MP gel formed a more porous network than the inner layer. This work is expected to give some insights into the development of promising salt-reduced meat products by microwave heating.
Asunto(s)
Microondas , Proteínas Musculares , Miofibrillas , Sodio , Agua , Agua/química , Animales , Miofibrillas/química , Miofibrillas/efectos de la radiación , Proteínas Musculares/química , Sodio/química , Conformación Proteica , Geles/química , Productos de la Carne/análisis , Porcinos , CalorRESUMEN
The effect of shrimp deveining on the quality of Pacific white shrimp muscle was investigated by analyzing the protein degradation during chilled storage via physicochemical and label-free peptidomics analyses. In this study, shrimp with intact intestines were in the control group (CS), while deveined shrimp (DS) were in the treatment group. The total viability count (TVC), total volatile base nitrogen (TVB-N) content, and trichloroacetic acid (TCA)-soluble peptide content in all of the shrimp groups gradually increased with prolonged chilled storage. However, in the later stages of chilled storage, the DS samples exhibited significantly lower TVB-N, total bacterial, and TCA-soluble peptide contents than the CS samples, indicating that deveining treatment effectively prolonged shrimp quality. The peptidomics analysis revealed varying degrees of protein hydrolysis in the DS and CS samples during chilled storage. A total of 396 differentially abundant peptides (DAPs) were identified in the DS compared with the CS, comprising 98 upregulated and 298 downregulated segments. This suggests that the removal of the intestine effectively inhibits protein hydrolysis. Gene ontology (GO) analysis suggested that the DAPs were mainly involved in catalytic activity, binding, and metabolic processes. The cluster of orthologous groups of protein (COG) analysis showed that the cytoskeleton dynamics of the muscle proteins underwent considerable alterations influenced by the shrimp's intestines during chilled storage.
Asunto(s)
Almacenamiento de Alimentos , Intestinos , Penaeidae , Animales , Penaeidae/química , Intestinos/química , Mariscos/análisis , Proteómica , Péptidos/química , Péptidos/análisis , Músculos/química , Músculos/metabolismo , Proteínas Musculares/química , Proteínas Musculares/metabolismoRESUMEN
This study investigated the effects of two forms of curdlan, namely curdlan thermoreversibility (CT) and curdlan powder (CP), on in vitro digestion and viscoelastic properties of myofibrillar protein (MP). As the level of curdlan (0.1-0.5%) increased, pepsin digestibility and pancreatin digestibility significantly decreased, active sulfhydryl group also decreased, while surface hydrophobicity and total sulfhydryl groups increased. Meanwhile, curdlan enhanced the secondary and tertiary structures of MP. As the pepsin digest, α-helix gradually transformed into random coil. Furthermore, the viscosity, storage modulus (G") and loss modulus (G') increased with the CT or CP addition. After in vitro digestion, the viscoelasticity significantly decreased with a dose-response. Molecular dynamics simulations showed hydrogen bond formation (2.86 on average) between MP and curdlan contributing to reduced radius of gyration and solvent accessible surface area. Overall, this study highlighted curdlan as a promising ingredient to modulate structural properties and digestibility of MP, especially in pre-hydrated (CT) groups.
Asunto(s)
Digestión , Reología , beta-Glucanos , beta-Glucanos/química , beta-Glucanos/metabolismo , Viscosidad , Animales , Proteínas Musculares/química , Interacciones Hidrofóbicas e Hidrofílicas , Simulación de Dinámica Molecular , PorcinosRESUMEN
In this study, the effect of ultrasound-assisted non-covalent binding of different polyphenols (tannins, quercetin, and resveratrol) on the structure and functional properties of myofibrillar proteins (MP) from the golden threadfin (Nemipterus virgatus) was investigated. The effect of ultrasound-assisted polyphenol incorporation on the structure and properties of MP was evaluated by multispectral analysis, interfacial properties, emulsification properties and antioxidant properties et al. The results revealed that the protein-polyphenol interaction led to a conformational change in the microenvironment around the hydrophobic amino acid residues, resulting in an increase in the equilibrium of the MP molecules in terms of affinity and hydrophobicity. Ultrasound assisted polyphenols addition also led to a significant decrease of the oil/water interfacial tension (from 21.22 mN/m of MP to 8.66 mN/m of UMP-TA sample) and a significant increase of the EAI (from 21.57 m2/g of MP to 28.79 m2/g of UMP-TA sample) and ES (from 84.76 min of MP to 124.25 min of UMP-TA). In addition, ultrasound-assisted polyphenol incorporation could enhance the antioxidant properties of MP, with the DPPH and ABTS radical scavenging rate of UMP-TA increase of 47.7 % and 55.2 % in comparison with MP, respectively. The results demonstrated that the noncovalent combination with polyphenols under ultrasound-assisted conditions endowed MP with better functional properties, including solubility, emulsification, foaming, and antioxidant properties through structure change. This study can provide innovative theoretical guidance for effectively preparing aquatic protein-polyphenol non-covalent complexes with multiple functions and improving the processing and utilization value of aquatic proteins.
Asunto(s)
Antioxidantes , Polifenoles , Ondas Ultrasónicas , Polifenoles/química , Animales , Antioxidantes/química , Proteínas Musculares/química , Interacciones Hidrofóbicas e Hidrofílicas , Miofibrillas/química , Unión Proteica , PecesRESUMEN
This study investigated the effect of different magnetic field treatments (0, 3, 6, 9, 12 mT) on the structure and emulsification properties of myofibrillar protein (MP). The results showed that the emulsion stabilized by MP with 3, 6, 9 mT magnetic field treatments possessed higher emulsifying ability, storage stability and apparent viscosity, since magnetic field induced the structural unfolding of MP and exposed the hydrophobic groups (the surface hydrophobic increased from 30.10 to 43.73 µg). Meanwhile, the magnetic field treatments decreased the MP particle size from 1752.00 to 1278.67 nm, which was favorable for the diffusion and adsorption of proteins at the oil-water interface, thus improving the MP emulsification ability and stability. Furthermore, the 9 mT magnetic field-treated MP had the best ability to emulsify oil droplets with a more uniform and smaller emulsion size from 28.593 to 23.443 µm. However, high-intensity magnetic field treatment (12 mT) caused MP particles to aggregate and the hydrophobic binding sites to be buried, which was not conducive to encapsulating oil droplets.
Asunto(s)
Emulsiones , Interacciones Hidrofóbicas e Hidrofílicas , Campos Magnéticos , Proteínas Musculares , Emulsiones/química , Proteínas Musculares/química , Conformación Proteica , Viscosidad , Tamaño de la Partícula , Animales , Miofibrillas/químicaRESUMEN
This study evaluated the effects of five thawing methods (air thawing (AT), water thawing (WT), plasma-activated water thawing (PT), ultrasound-assisted water thawing (UWT) and ultrasound-assisted plasma-activated water thawing (UPT)) on the physicochemical, thermal stability, rheological, and structural properties of porcine longissimus dorsi myofibrillar protein (MP). UPT treatment significantly improved protein solubility (73.10%) and reduced protein turbidity (0.123) compared with AT, WT, and PT treatments (P < 0.05). UPT treatment reduced the MP particle size (635.50 nm) and zeta potential (-6.38 mV) compared with AT and WT treatments (P < 0.05), which was closer to that of the fresh sample. UPT treatment also maintained the MP surface hydrophobicity and thermal stability. UPT treatment improved the MP rheological properties of the sample. In addition, UPT treatment effectively protected the MP secondary and tertiary structures. In conclusion, UPT treatment better maintained the MP physicochemical, thermal stability, rheological, and structural properties of thawed porcine longissimus dorsi. Therefore, UPT treatment can be considered as an effective thawing method.
Asunto(s)
Proteínas Musculares , Reología , Agua , Animales , Porcinos , Agua/química , Proteínas Musculares/química , Miofibrillas/química , Estabilidad Proteica , Solubilidad , Músculo Esquelético/química , Interacciones Hidrofóbicas e Hidrofílicas , Calor , CongelaciónRESUMEN
The interaction between proteins and soluble dietary fibers plays a vital role in the development of animal-derived foods. Herein, the effects of different contents (0-3.0%) of round-bracted psyllium husk powder (PHP) on the gelation behavior, microstructure, and intermolecular interactions of Andrias davidianus myofibrillar protein (MP) were investigated. Rheological and chemical forces suggested that PHP (1.5%-2.0%) enhanced the functional properties of MP at low ionic strength, thereby increasing the viscoelasticity of mixed gels. SDS-PAGE revealed that PHP reinforced the cross-linking and aggregation of protein molecules. Circular dichroism spectroscopy, low-field nuclear magnetic resonance, and scanning electron microscopy demonstrated that PHP induced the transformation of α-helix (decreased by 14.85%) to an ordered ß-sheet structure (increased by 81.58%), which was more favorable for the formation of dense network structure and improved (10.53%) the water retention of MP gels. This study provided new insights for PHP to effectively meliorate the heat-induced gelling properties of MP.