Dynamic Rheological Properties Research Articles

Grape pomace high-methoxyl pectin: A new prebiotic stabilizer for low-fat synbiotic yogurt gels – Optimization and characterization

High-methoxyl pectin (HMP, 72.5 % esterification degree and galacturonic acid content of 67.9 %) was extracted from grape pomace using a sequential ultrasound-microwave extraction. The extracted HMP was used to develop low-fat synbiotic set yogurts containing probiotic cells. Higher grape pomace pectin (GPP) concentrations (0.5–2 %) increased the probiotic bacterial population of Lactobacillus acidophilus LA-5 and Bifidobacterium bifidum BB-12. Higher cell viability was observed for L. acidophilus LA-5 compared to B. bifidum BB-12. A response surface optimization showed that the presence of 8.08 Log CFU mL−1L. acidophilus LA-5 and 1.88 % HMP experimentally resulted in the best probiotic viability (10.83 ± 0.11 Log CFU mL−1), overall acceptability (8.03 ± 0.06), and pH (4.25 ± 0.05) values. Compared to pectin-free probiotic yogurts, the optimal yogurt gels presented higher probiotic survivability, lower syneresis, and superior storage-dependent sensory attributes during 21 days of storage. However, a 14-day storage period was generally deemed suitable. The GPP-containing yogurt compared to the pectin-free sample exhibited higher colloidal stability with a larger particle size (433.8 nm vs. 272.5 nm) and lower zeta potential (−20.4 mV vs. −10.6 mV). Field emission-scanning electron (FE-SEM) and fluorescent (FLM) microscopy images confirmed a denser microstructure for GPP-enriched yogurts. The chemical interactions in the yogurt were not affected by enriching with GPP as investigated by FTIR, whereas the steady and dynamic rheological properties were significantly improved. GPP-enriched yogurt had a firmer gel structure with a larger linear region and lower G′ compared to the control, indicating a semi-solid state. The GPP as a multi-functional prebiotic ingredient would be promising in designing healthier food products.

Improving the rheological properties of ultra-processed powdered goat milk beverage using texture additives.

This study aimed to investigate the static and dynamic rheological properties of an ultra-processed powdered goat milk beverage containing carboxymethyl cellulose (CMC), guar gum (GG), and xanthan gum (XG), using a mixture design. Fourteen samples were evaluated, in addition to the original beverage. The flow curves classified the fluids as non-Newtonian and characterized all the reconstituted beverages with pseudoplastic behavior, precisely due to the addition of hydrocolloids that increased the viscosity, and the fresh beverage sample showed the behavior of a dilatant fluid. The stress sweep verified the changes in the storage module (G') and the loss module (G″), the G' ranged from 1.97 to 20.36 (Pa) and the G″ ranged from 5.94 to 11.30 (Pa), demonstrating that there was the formation of beverages with elastic and viscous behaviors. The results showed a synergistic effect between the texture improvers, and the formulations with GG identified a greater effect on the tension. The frequency sweep tests showed that the behavior of the samples was that of a weak gel; however, when subjected to a certain frequency, the values of G' exceeded the value of G″, becoming a sample with more elastic characteristics and consequently, presenting the behavior of a stronger gel. Finally, according to the data presented, it is assumed that formulations containing GG and xanthan gum may produce desirable consumer properties for the reconstituted goat milk drink. Samples with a higher concentration of GG exhibited improved rheological performance, characterized by greater consistency, increased resistance to tension, and higher viscosity at low frequencies. PRACTICAL APPLICATION: The powdered goat milk drink is an innovative product that meets the demands of the food industry and consumers by offering a nutritious and sustainable beverage alternative.

Effect of Flammulina velutipes Soluble Dietary Fiber on Dough Processing Characteristics and Micro-Fermented Dried Noodles Quality Properties.

Our research focused on the integration of Flammulina velutipes soluble dietary fiber (Fv-SDF) into wheat flour during the production of dried noodles, delving into the impact of different addition ratios of Fv-SDF on both dough processing characteristics and the quality of the micro-fermented dried noodles. The viscometric and thermodynamic analyses revealed that Fv-SDF notably improved the thermal stability of the mix powder, reduced viscosity, and delayed starch aging. Additionally, Fv-SDF elevated the gelatinization temperature and enthalpy value of the blend. Farinograph Properties and dynamic rheology properties further indicated that Fv-SDF improved dough formation time, stability time, powder quality index, and viscoelasticity. Notably, at a 10% Fv-SDF addition, the noodles achieved the highest sensory score (92) and water absorption rate (148%), while maintaining a lower dry matter loss rate (5.2%) and optimal cooking time (142 s). Gas chromatography-ion mobility spectrometry (GC-IMS) analysis showed that 67 volatile substances were detected, and the contents of furfural, 1-hydroxy-2-acetone, propionic acid, and 3-methylbutyraldehyde were higher in the Fv-SDF 10% group. These 10% Fv-SDF micro-fermented noodles were not only nutritionally enhanced, but also had a unique flavor. This study provides a valuable theoretical basis for the industrial application of F. velutipes and the development of high-quality dried noodles rich in Fv-SDF.

Investigate the influence of GO as an additive in the silica-based polyethylene glycol shear thickening fluid on the rheological properties

Abstract Shear thickening fluids (STF) represent stabilized and concentrated colloidal suspensions, wherein hard nanoparticles are dispersed within a liquid medium (polymer). Under the influence of impact forces, they exhibit non-Newtonian behavior, effectively dissipating energy through shear thickening. The optimization of the dispersion medium’s viscosity is critical, as it not only fosters shear thickening but also facilitates proper particle dispersion. This study investigates the impact of graphene oxide (GO) as an additive in STFs, analyzing both static and dynamic rheological properties. STFs were formulated using colloidal silica particles (600 nm) and polyethylene glycol (PEG-200), with varied concentrations of GO particles (0.12–0.5 % w/W). The systems underwent comprehensive analysis concerning steady-state and dynamic-state rheological behavior under diverse conditions. The findings reveal that the inclusion of GO augments both static and dynamic rheological properties, reaching an apex at an optimal concentration of 0.36 % w/W. GO functions as a network builder within the STF, interacting with the existing particle network to create a more robust and interconnected structure. These enhanced properties underscore the potential of the synthesized STF for applications requiring impact resistance.

Combined effects of nitrogen and sulfur fertilizers on chemical composition, structure and physicochemical properties of buckwheat starch

Buckwheat starch has attracted worldwide attention in the food industry as a valuable raw material or food additive. Nitrogen (N) and sulfur (S) are two nutrients essential to ensure grain quality. This study investigated the combined application of N fertilizer (0, 45 and 90 kg N ha−1) and S fertilizer (0 and 45 kg SO3 ha−1) on the chemical composition, structure and physicochemical properties of buckwheat starch. The results showed that increasing the fertilizer application decreased amylose content and starch granule size but increased light transmittance, water solubility and swelling power. The stability of the absorption peak positions and the decrease in short-range order degree suggested that fertilization influenced the molecular structure of buckwheat starch. In addition, increases in viscosity and gelatinization enthalpy as well as decreases in gelatinization temperatures and dynamic rheological properties indicated changes in the processing characteristics and product quality of buckwheat-based foods.

Quality analysis of dough and steamed bread under various freezing conditions.

Freezing is a crucial step in the process of frozen foods. In this study, the effects of different freezing methods, including liquid nitrogen immersion freezing (LF), quick-freezing machine freezing (QF), packaging immersion freezing (PF), and ultralow temperature refrigerator freezing (UF), and freezing time (0, 15, 30, and 60 days) on the textural properties, dynamic rheological properties, water distribution, and structure of dough and the quality of end steamed bread were evaluated. Freezing resulted in a decline in the physicochemical properties of dough. UF- and QF-doughs had higher storage modulus and loss modulus, compared with PF- and LF-doughs. LF enhanced the textural attributes of the dough, resulting in reduced hardness and increased springiness. At 15 days of freezing, QF- and LF-doughs exhibited a compact and continuous structure with a smooth surface. Additionally, the correlation analysis elucidated that the weight loss rate and the bound water content of the dough had discernible impacts on the texture of both the dough and the resulting steamed bread. Overall, LF demonstrated a relatively high freezing efficiency and effectively maintained the quality of the dough for up to 15 days of freezing. These results offer valuable insights for the applications of freezing methods and time in frozen foods.

Effects of Freeze-Thaw Cycles on the Quality of a Novel Mixed Grain Composite Dough and Its Product (Potato-Oat Yu): Hybridization of Potatoes and Oats.

To provide a theoretical basis for the frozen storage of potato-oat composite dough and its products, this investigation examines changes in the quality of potato-oat composite dough and its resulting product during freeze-thaw cycles. The study measured key aspects such as moisture content, dynamic rheological properties, water state, protein secondary structure, color, and sensory assessment. The influence of these factors on the product's quality is analyzed. The findings revealed that the freeze-thaw treatment caused a reduction in water content, freezable water, and deeply bound water, as well as an increase in weakly bound water, β-sheet, random coil, and α-helix, and a decreased β-turn of the potato-oat composite dough. Additionally, the dough treated by freeze-thaw cycles resulted in darker color, and the sensory properties of the product were affected significantly after exceeding three freeze-thaw cycles. Moreover, an increase in the number of freeze-thaw cycles resulted in an upward trend of moisture content for the composite dough, whereas G' initially increased and then decreased. The G″ of the composite dough peaked after the third freeze-thaw cycle. Overall, the composite dough quality significantly deteriorated at the fourth freeze-thaw cycle. There was a significant increase in the freezable water content, the largest modulus of elasticity, and the smallest tan δ. Therefore, the usage of the potato-oat composite dough should not exceed three cycles.

Understanding the dynamic rheological property of cement paste blended with steel slag powder: From interparticle force and physico-chemical parameters of view

The blending of steel slag powder with cement can mitigate the carbon footprint of cementitious composites. The rheological properties of cement pastes are well known to be related to interparticle forces. However, the magnitude of the interparticle force depends on many physico-chemical factors. The influence of various factors on interparticle forces is not yet clear, making it difficult to control the rheological properties. In this paper, the interparticle force of steel slag powder blended cement paste was quantified and its relationships with dynamic rheological properties and basic physico-chemical parameters were explored. By means of this, the interparticle force was confirmed to could explain the effect of steel slag powder on the dynamic rheological properties of cement paste within 1 h. Moreover, how physico-chemical parameters affect the interparticle forces was clarified. A cement paste with large particle size and apolar surface energy, as well as small potential square, Debye length and small polar surface energy, can exhibit large interparticle force and high dynamic yield stress and plastic viscosity. A simple formula calculating interparticle force from basic parameters was proposed, which is believed to effectively and practically regulate the interparticle force. The relationships between interparticle forces, physico-chemical parameters, and rheological properties provide an effective reference for regulating the dynamic rheological properties of cement paste through fundamental parameters.

Effects of whole wheat flour on frozen dough and steamed bread during freeze-thaw cycles

The research on Chinese steamed bread (CSB) with whole wheat flour (WWF) is limited and has not been discussed during freeze-thaw. This study investigated the effects of WWF addition on the dough and CSB quality during freeze-thaw cycles. The results of low-field nuclear magnetic resonance (LF-NMR) and dynamic rheological properties demonstrated that the WWF reduced the adverse changes of freeze-thaw treatment on the dough. Characteristics, texture, and cross section analysis of CSB showed that WWF (20%) could relatively maximize stability. To study the mechanism, arabinoxylan (AX) and water-extractable arabinoxylan (WEAX) from WWF were added to dough. Consistent with WWF, it was found that they could improve freeze-thaw tolerance of frozen dough and CSB. Meanwhile, WEAX (1.12%) could better increase quality and freeze-thaw tolerance of CSB. The results presented in the study indicate that the anti-freeze-thaw effects of WWF could be attributed to AX and WEAX.

Effect of curdlan on improving dough rheological properties and performance of corresponding steamed bread

This study explored the effect of curdlan on dough rheological properties, and the performance of corresponding steamed bread. Curdlan addition significantly improved the rheological, dynamic rheological and fermentation properties of dough, and ultimately enhanced the textural and sensory properties of corresponding steamed bread. The microstructure confirmed that the dough with 0.5% curdlan had uniform size and dense gluten network. Addition of curdlan also increased the pasting temperature, the peak and final viscosities, but decreased the breakdown and setback parameters of starch. The steamed bread with 0.5% curdlan had minimum hardness (1266 g), maximum specific volume (2.50 mL/g) and highest sensory score (92.0). Storage experiments suggested that 0.5% curdlan decreased the crumb firming rate and alleviated the retrogradation of starch in steamed bread, indicating that curdlan was effective in retarding the steamed bread staling during storage. It was concluded that 0.5% curdlan had positive effect on rheological properties of wheat dough and quality of corresponding steamed bread.

Olive Pomace Oil Structuring for the Development of Healthy Puff Pastry Laminating Fats: The Effect of Chilling Storage on the Quality of Baked Products.

Developing puff pastry (PP) laminating fats (LFs) with sustainable structured olive pomace oil (OPO) could contribute to its increased valorization. This study evaluated the physicochemical stability of four OPO-based LFs or margarines and the performance of their baked PP counterparts during two months of chilling storage at 4 °C. LF samples, developed at the laboratory scale, contained 41% (LF1 and LF2) OPO and 31% (LF3 and LF4) OPO together with 10% cocoa butter when using two static initial crystallization conditions (room temperature for LF1 and LF3, freezer for LF2 and LF4) before storage. During the storage period, the proximate composition, thermal and dynamic rheological properties, firmness and spreadability, oil-binding capacity, color, and lipid oxidation of the four LF samples were examined, along with the baking performance and textural properties of the PP counterparts. The initial cooling rate had minimal significance. Cocoa butter negatively influenced post-crystallization processes occurring in OPO-based LF3 and LF4, resulting in increased hardness and reduced performance after 18 days of storage, attributed, at least partially, to a high amount of 1,3-dipalmitoyl-2-oleoyl-glycerol (POP), mainly from cocoa butter. Conversely, OPO-based LF1 and LF2 maintained their quality and were stable for two months without apparent granular crystal formation.

Influence of particle network characteristics on the dynamic rheological properties of red lentil puree fractions

The complex cellular structure of plant-based purees has a great impact on their rheological properties, as affected by particle-related factors such as their shape, size and concentration. The aim of this study was to unravel the impact of particles characteristics on viscoelastic properties of fractions from a red lentil puree containing high contents of starch and protein. Four particle fractions were separated from the puree: cell fragments (CF), single cells (SC), cell clusters (CC), and a mix of all particles (MP). Their composition, structural properties, stability upon dilution and dynamic rheological properties after reconstitution at three pulp contents were investigated. CF was mostly made of aggregated cell fragments containing extracellular starch, SC was characterized by dispersed parenchyma cells filled with intracellular starch, and CC of cell clusters containing some intracellular starch. The viscoelastic properties seemed driven by starch location, as SC and CC had higher power law constant values (K') and flow stress (σf), with lower yield strain (γy) than CF: extracellular starch could form a continuous entangled network, entrapping particles and decreasing the gel strength. CF was also the most stable to dilution, which emphasized the role of extracellular starch on networks cohesion. K' and σf were higher in CC than in SC, probably because of the roughness of cell clusters assessed by their low solidity values, as opposed with single cells of smoother surface. Such work on pulse puree particle networks helped to understand the mechanisms involved in a complex structured food system rich in starch and protein.

Polysaccharide from Clitocybe squamulosa: Gel-forming properties and its compound effect with food thickener

To study the gel-forming properties of polysaccharide from the fruiting body of Clitocybe squamulosa (CSFP) and its degradation product (UH-CSFP), the changes in steady-state and dynamic rheological properties of CSFP and UH-CSFP under different conditions (polysaccharide mass fraction, temperature, pH, and salt ion concentration) were studied. Polysaccharides with good gel-forming properties were selected and mixed with common edible thickeners (gelatin, guar gum, and locust bean gum), after which the properties of the composite gel were assessed. The steady-state rheological results showed that CSFP and UH-CSFP were pseudoplastic fluids, their apparent viscosity decreased with increasing temperature, the viscosity was greatest when the pH was 7. The addition of Na+ and Ca2+ could increase the viscosity, and the viscosity of UH-CSFP was lower than that of CSFP at the same mass fraction. The results of dynamic rheology indicated that G´ and G´´ of CSFP and UH-CSFP increased with increasing mass fraction, pH, and ion concentration (0.01 M to 1 M), and G´´ was always smaller than G´ indicating weak gel behavior. The thixotropy-related experimental results showed that the thixotropy ring area of CSFP and UH-CSFP increased with increasing mass fraction, the ring area of CSFP was larger than that of UH-CSFP, and the gel strength of CSFP was greater than that of UH-CSFP. The results of CSFP and three types of edible gels showed that the composite gels were pseudoplastic fluids, and their apparent viscosity was ranked (in descending order) as follows: guar bean gum, locust bean gum, and gelatin. The addition of CSFP improved the gel-forming properties of guar gum but did not significantly improve the gel properties of locust bean gum and gelatin. This study provides a theoretical basis for the selection of processing methods and the application of polysaccharides.

Incorporation of Lepidium perfoliatum seed gum into wheat starch affects its physicochemical, viscoelastic, pasting and freeze-thaw syneresis properties

This study aimed to investigate the influence of incorporating Lepidium perfoliatum seed gum (LPSG) into wheat starch (WS) at various mixing ratios on its FTIR, DSC, steady and dynamic rheological properties, pasting attributes, syneresis, and particle size distributions characteristics. The interaction between WS and LPSG was purely based on hydrogen-bonding. It was found that the onset (To) and peak (Tp) temperatures of the LPSG-rich mixtures increased by 10 % and 8 %, respectively, while the enthalpy (ΔH) decreased by 70 % compared to WS. A higher LPSG ratio led to a decrease in the frequency dependence of storage modulus (G′), as well as an increase in the pseudoplasticity of the mixtures. The in-shear structural recovery test showed that the rate of recovery (R, %) increased with an increasing LPSG ratio. The pasting results demonstrated that the 9/1 ratio had the highest final viscosity and the lowest relative breakdown. Applying 1 to 5 freeze-thaw cycles resulted in a 50 % to 70 % decrease in syneresis for the 9/1 mixing ratio in comparison to WS, respectively. The incorporation of LPSG into WS resulted in higher static and dynamic magnitudes of yield stress, as well as an increase in particle size when compared to WS.

Characterization of the Starch Extracted from an Ancestral Andean Meal: Chuño

AbstractThe ancestral method of preparing chuño (freeze‐dried potato) involves three steps: freezing, soaking, and drying. The objective of this study is to identify the changes in microstructure, in physicochemical properties, and rheology of gels and suspensions of Andean potato starches caused by the procedure used to obtain chuño. A laboratory simulation of the procedure is performed using the potato variety “Rosadita” (Solanum tuberosum ssp. Andigenum). From the tests carried out on the starches extracted from the chuño obtained in the field and in the laboratory, differences phosphate content and gelatinization temperature are found. Marked differences are observed with respect to the control starch in the soluble amylose content, RVA profiles, textural attributes, and dynamic and viscous rheological properties. The chuño starches present greater resistance to granular breakdown. These observations suggest a different hydration, swelling, and gelation mechanism for the Rosadita and chuño starch samples compared to conventional potato starch and at the same time a modification due to the effect of freezing, which is more noticeable in the chuño obtained at −5 °C.

Egg white improved the quality of noodles with high mung bean content by protein aggregation behavior

AbstractBackground and ObjectivesMung bean, as a coarse grain, is rich in protein and phytochemicals. Noodles prepared from mung bean are nutritionally superior to traditional noodles. However, the absence of gluten protein in mung bean limits their incorporation level and might cause adverse effects on the quality of noodles. To address the quality degradation of noodles with high mung bean content due to the lack of gluten proteins, the effects of fresh egg white on their quality improvement were investigated. In this study, the dynamic rheological properties of the dough as well as the changes in free sulfhydryl and SS bonds were determined. The cooking characteristics, sensory, textural properties, and microstructure of the noodles were evaluated.FindingsResults revealed that the addition of 15% fresh egg white significantly improved the sensory scores of the wheat–mung bean (3:7) composite noodles, which might be attributed to the enhanced modulus of elasticity (G′) of the composite dough system, the increased hydrophilicity, and amount of free sulfhydryl and SS bonds in noodles. Meanwhile, scanning electron microscopy and confocal laser scanning microscopy further confirmed that the addition of 15% fresh egg white affected the structures of starch granule and protein network. Furthermore, the addition of 15% fresh egg white minimized the cooking loss and enhanced the springiness, adhesiveness, and chewiness of the noodles, which in turn resulted in the highest sensory scores.ConclusionsThe incorporation of 15% fresh egg white could enhance the quality characteristics of mung bean noodles by protein aggregation, thus receiving a favorable acceptance.Significance and NoveltyThis study explored the possibility of developing a novel noodle with 70% mung bean content. Moreover, the addition of 15% fresh egg white could significantly improve its quality and overall acceptability. This result contributes to the development of high‐content gluten‐free cereal or other legume noodles.

Rheological and thermal properties of an enteral nutrition formula for nutritional support patients using a combined mixture of gelatin and maltodextrin.

Enteral nutrition is a type of nutritional support that provides the necessary sources of energy and protein for patients who suffer from dysphagia, chronic disease, and loss of appetite. In this study, a gelatin-maltodextrin binary biopolymer system has been incorporated into a semi-solid formula. The I-optimal combination design approach was used to create 19 formulations, and the dynamic rheological properties, dynamic laser scattering, and zeta potential responses were evaluated over 30 days of storage at 5°C. Solid viscoelastic behavior has been approved since G' > G″ in the frequency sweep test with no cross-over point. Maltodextrin may interfere within the gelatin network, and increasing the maltodextrin to gelatin (from 0.14 to 1) may lead to a wider linear viscoelastic (LVE) strain range (2.16%), a lower storage modulus at LVE (52%), a lower yield stress (46%), and a lower glass transition temperature (34%). The presence of maltodextrin may reduce the temperature of the sol-to-solid transformation by 48% and enhance its flexibility. In contrast, increasing the gelatin-to-maltodextrin ratio following melting at 37°C led to an increase in the cumulant mean and polydispersity index, indicating a relatively unstable system. The range of zeta potential values between -4.4 and 1.7 mV confirmed a tendency toward coagulation. Microscopic images revealed instability because of irregular or compact chains formed in the gelatin matrix by using higher amounts of maltodextrin. Finally, the best formula had the best rheological stability and was suitable for tube-feeding patients, with a gelatin-to-maltodextrin ratio of 4.35:3.64% w/w on day 17.4.

Effect of re-aging on chemical and rheological properties of waste engine oil rejuvenated asphalt binder

The use of rejuvenator can potentially restore original properties of reclaimed asphalt pavement (RAP) materials to achieve the purpose of reuse, but less attention has been paid to the aging properties of rejuvenated asphalt binders. In this study, original asphalt binder, aged binder and the rejuvenated binders with 3 %, 6 %, and 9 % of rejuvenator by total weight of binder were prepared first. Then the five rejuvenated binders were subjected to the oven aging. Based on the results from Fourier Transform Infrared Spectroscopy and Dynamic Shear Rheometer, the chemical and rheological properties of the five binders were investigated due to re-aging. It is showed that the of carbonyl index of the rejuvenated binders and original binder increase rapidly during the fast-aging state and then slowly during the constant-aging state, while aged binder increases approximately linearly. The rheological properties indexes such as complex shear modulus, phase angle δ, crossover frequency, crossover modulus, rheological index, G-R parameter and rutting factor of the five binders were determined, and the variation of these indexes are similar or opposite to carbonyl index during aging. Aging performances of the five binders were investigated using the oven aging indexes. It is showed the rejuvenated binders with more dosage of rejuvenator have faster aging rate and more obvious effects on the aging rheological behavior. The rheological properties of the aged binder are less affected by the re-aging. Among the rheological property indexes, the G-R-based oven aging index is most susceptible to the re-aging. There are some certain close relationships between the chemical property change and rheological property evolution during re-aging for the five binders, without considering the aging times and the dosage of rejuvenator.

Effects of 2,2'-Azobis(2-methylpropionamidine) Dihydrochloride Stress on the Gel Properties of Duck Myofibrillar Protein Isolate.

The aim of this study was to investigate the biochemical properties and gel-forming capacity of duck myofibrillar proteins under the effects of 2,2'-azobis(2-methylpropionamidine) dihydrochloride (AAPH)-mediated oxidation. Duck myofibrillar proteins were extracted and treated with different concentrations of AAPH solutions (0, 1, 3, 5, 10 mmol/L) and then analysed for carbonyl content, dynamic rheology, protein profiles and gel-forming properties (colour, water holding capacity, gel strength and microstructure). The results showed that with increasing AAPH concentration, the carbonyl content of the proteins exhibited an increasing trend (p < 0.05); SDS-PAGE pattern changes indicated that moderate oxidation (3 mmol/L AAPH) induced myosin aggregation via covalent bonds including disulfide, enhanced protein-protein interactions, and thus affected the gel strength of the DMPs' heat-induced gels. However, high oxidation (5 and 10 mmol/L AAPH) led to the partial degradation of the myosin heavy chain (MHC) isoforms, as evidenced by lower storage modulus and irregular microstructures, which significantly reduced gelation ability. These results suggest that the internal relationship between alkylperoxyl radical-induced oxidation should be taken into account in the processing of duck meat, as mild protein oxidation is conducive to improving gel quality.

Exploring the relationship between the interfacial properties and emulsion properties of ultrasound-assisted cross-linked myofibrillar protein

This work aimed to illustrate the correlation between the dynamic adsorption process of ultrasound-assisted cross-linked MP on the oil-water interface and the stability of the fabricated emulsion. The interfacial pressure, adsorption kinetic coefficient, dynamic rheological properties of crosslinked MP (E-MP5), sonication before MP crosslinking (E-UMP5), and sonication after MP crosslinking (E-MPU5) and the corresponding emulsion properties, adsorbed proteins, microrheological properties, and multiple light scattering were determined. The results showed that the emulsion properties were positively correlated with the interfacial properties of MP. Ultrasound treatment could more effectively improve the interfacial properties and emulsion stability of the MP molecules than the Native treatment. Among the ultrasonic groups, the E-MPU5 group exhibited the highest interfacial pressure (15.81 mN/m), diffusion rate (Kdiff), penetration rate (KP), rearrangement rate (KR), dilatational modulus, elastic modulus, and E-π slope (2.65). Correspondingly, based on the change of Kdiff, KP, and KR, E-MPU5-fabricated emulsion had the lowest droplet size (1.56 μm), the maximum adsorbed protein content (93.08%), and the highest absolute zeta potential value. Additionally, the decreased viscosity, elastic index, macroscopic viscosity index, and turbiscan stability index in the E-MPU5-fabricated emulsion indicated the formation of a more stable emulsion. Therefore, this work suggests that sonication after crosslinking could greatly improve the interfacial adsorption behavior of MP, and the improvement of interfacial properties is conducive to the enhancement of emulsion stability.