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1.
J Food Sci ; 89(7): 4419-4429, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38957111

RESUMO

The objective of this research was to evaluate changes in flow behavior of chocolate during chocolate grinding using a stone grinder as affected by chocolate formulation. Three different types of chocolates were evaluated. Two chocolates without milk added (70% chocolate) and two chocolates with milk added and with different amounts of cocoa nibs (30% chocolate and 14% chocolate) were tested. For the 70% chocolates, nibs of two different origins were used; therefore, a total of four samples were evaluated. Chocolates were processed in a stone grinder, and samples were taken as a function of grinding time. For each timepoint, the flow behavior of the samples was measured using a rotational rheometer and fitted to the Casson model. Particle size was measured using a laser scattering instrument. Results showed that yield stress increased linearly while the Casson plastic viscosity decreased exponentially with grinding time (smaller particles). Particle size distribution of the chocolates showed a prominent bimodal distribution for short grinding times (∼9 h) with small (∼15 µm) and large (∼100 µm) particles; with longer grinding time, the population of larger particles decreased. Yield stress values were higher for the 70% chocolate, but they were not very different between the two milk chocolates tested. The Casson plastic viscosity was greatest for the 70% chocolate, followed by the 30% chocolate. The 14% chocolate had the lowest Casson plastic viscosity. Changes of Casson plastic viscosity with particle size were more evident for the dark chocolates compared to the milk ones. These results are helpful to small chocolate producers who need better understanding of how the formulation and grinding of chocolate affect its flow behavior, which will ultimately affect chocolate handling during production.


Assuntos
Chocolate , Manipulação de Alimentos , Leite , Tamanho da Partícula , Chocolate/análise , Manipulação de Alimentos/métodos , Viscosidade , Leite/química , Reologia , Cacau/química , Animais
2.
Commun Biol ; 7(1): 786, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38951579

RESUMO

Fibroins' transition from liquid to solid is fundamental to spinning and underpins the impressive native properties of silk. Herein, we establish a fibroin heavy chain fold for the Silk-I polymorph, which could be relevant for other similar proteins, and explains mechanistically the liquid-to-solid transition of this silk, driven by pH reduction and flow stress. Combining spectroscopy and modelling we propose that the liquid Silk-I fibroin heavy chain (FibH) from the silkworm, Bombyx mori, adopts a newly reported ß-solenoid structure. Similarly, using rheology we propose that FibH N-terminal domain (NTD) templates reversible higher-order oligomerization driven by pH reduction. Our integrated approach bridges the gap in understanding FibH structure and provides insight into the spatial and temporal hierarchical self-assembly across length scales. Our findings elucidate the complex rheological behaviour of Silk-I, solutions and gels, and the observed liquid crystalline textures within the silk gland. We also find that the NTD undergoes hydrolysis during standard regeneration, explaining key differences between native and regenerated silk feedstocks. In general, in this study we emphasize the unique characteristics of native and native-like silks, offering a fresh perspective on our fundamental understanding of silk-fibre production and applications.


Assuntos
Bombyx , Fibroínas , Bombyx/metabolismo , Bombyx/química , Animais , Fibroínas/química , Fibroínas/metabolismo , Reologia , Seda/química , Seda/metabolismo , Concentração de Íons de Hidrogênio
3.
J Texture Stud ; 55(4): e12855, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38992897

RESUMO

The effects of oil type, emulsifier type, and emulsion particle size on the texture, gel strength, and rheological properties of SPI emulsion-filled gel (SPI-FG) and TFSP emulsion-filled gel (TFSP-FG) were investigated. Using soybean protein isolate or sodium caseinate as emulsifiers, emulsions with cocoa butter replacer (CBR), palm oil (PO), virgin coconut oil (VCO), and canola oil (CO) as oil phases were prepared. These emulsions were filled into SPI and TFSP gel substrates to prepare emulsion-filled gels. Results that the hardness and gel strength of both gels increased with increasing emulsion content when CBR was used as the emulsion oil phase. However, when the other three liquid oils were used as the oil phase, the hardness and gel strength of TFSP-FG decreased with the increasing of emulsion content, but those of SPI-FG increased when SPI was used as emulsifier. Additionally, the hardness and gel strength of both TFSP-FG and SPI-FG increased with the decreasing of mean particle size of emulsions. Rheological measurements were consistent with textural measurements and found that compared with SC, TFSP-FG, and SPI-FG showed higher G' values when SPI was used as emulsifier. Confocal laser scanning microscopy (CLSM) observation showed that the distribution and stability of emulsion droplets in TFSP-FG and SPI-FG were influenced by the oil type, emulsifier type and emulsion particle size. SPI-stabilized emulsion behaved as active fillers in SPI-FG reinforcing the gel matrix; however, the gel matrix of TFSP-FG still had many void pores when SPI-stabilized emulsion was involved. In conclusion, compared to SPI-FG, the emulsion filler effect that could reinforce gel networks became weaker in TFSP-FG.


Assuntos
Emulsificantes , Emulsões , Géis , Tamanho da Partícula , Reologia , Proteínas de Soja , Proteínas de Soja/química , Emulsões/química , Emulsificantes/química , Géis/química , Óleos de Plantas/química , Óleo de Palmeira/química , Óleo de Brassica napus/química , Óleo de Coco/química , Dureza , Caseínas/química , Gorduras na Dieta
4.
Opt Lett ; 49(13): 3600-3603, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950219

RESUMO

Visualizing a 3D blood flow velocity field through noninvasive imaging is crucial for analyzing hemodynamic mechanisms in areas prone to disorders. However, traditional correlation-based optical coherence tomography (OCT) velocimetry techniques have a maximum measurable flow velocity depending on the A-line rate. We presented the ergodic speckle contrast OCT (ESCOCT) to break the bottleneck in measuring the rapid blood flow velocity. It achieved a measurement of blood flow velocity ranging from 9.5 to 280 mm/s using a 100 kHz swept-source (SS) OCT based on 100 A-repeats scanning mode. Addressing the non-ergodic problem of temporal OCT signals by integrating more consecutive A-scans, ESCOCT can enable the estimation for lower velocity flows by increasing A-repeats. ESCOCT provided a wide dynamic range with no upper limit on measuring blood flow velocity with an adequate signal-to-noise ratio and improved the sensitivity and accuracy of the hemodynamic assessment.


Assuntos
Tomografia de Coerência Óptica , Tomografia de Coerência Óptica/métodos , Velocidade do Fluxo Sanguíneo/fisiologia , Reologia/métodos , Humanos , Razão Sinal-Ruído
5.
J Texture Stud ; 55(4): e12852, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38952166

RESUMO

The development of thickening powders for the management of dysphagia is imperative due to the rapid growth of aging population and prevalence of the dysphagia. One promising thickening agent that can be used to formulate dysphagia diets is basil seed mucilage (BSM). This work investigates the effects of dispersing media, including water, milk, skim milk, and apple juice, on the rheological and tribological properties of the BSM-thickened liquids. Shear rheology results revealed that the thickening ability of BSM in these media in ascending order is milk < skim milk ≈ apple juice < water. On the other hand, extensional rheology demonstrated that the longest filament breakup time was observed when BSM was dissolved in milk, followed by skim milk, water, and apple juice. Furthermore, tribological measurements showed varying lubrication behavior, depending on the BSM concentration and dispersing media. Dissolution of BSM in apple juice resulted in the most superior lubrication property compared with that in other dispersing media. Overall, this study provides insights on BSM's application as a novel gum-based thickening powder in a range of beverages and emphasizes how important it is for consumers to have clear guidance for the use of BSM in dysphagia management.


Assuntos
Ocimum basilicum , Mucilagem Vegetal , Reologia , Sementes , Ocimum basilicum/química , Sementes/química , Mucilagem Vegetal/química , Animais , Leite/química , Viscosidade , Transtornos de Deglutição , Malus/química , Sucos de Frutas e Vegetais/análise , Humanos , Água , Pós , Lubrificação
6.
J Texture Stud ; 55(4): e12850, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38952176

RESUMO

This study examined the effects of spread formulation and the structural/lubricant properties of six different commercial hazelnut and cocoa spreads on sensory perception. Rheology, tribology, and quantitative descriptive analysis (QDA) was assessed by also evaluating the correlation coefficients between the quality descriptor and the rheological and textural parameters. The viscosity was evaluated at different temperatures to better simulate conditions before and after ingestion. Tribological analysis was executed at 37°C to mimic the human oral cavity. The effect of saliva presence and the number of runs on tribological behaviors was investigated. Moreover, textural, calorimetric, and particle size distribution measurements were performed to reinforce the correlation between structural/thermal parameters (e.g., firmness, stickiness, sugar melting point) and sensory aspects. "Visual viscosity," defined as a sensory attribute evaluated prior to consumption, negatively correlated with apparent viscosity measured at 20°C and 10 s-1, whereas "body," defined during oral processing and related to creaminess, positively correlated with apparent viscosity measured at 37°C and 50 s-1. These attributes were mainly influenced by particulate microstructure and solid volume fraction within the formulation. Textural stickiness positively correlated with sensory "adhesiveness" and was related to fat composition and milk powder addition, while "sweetness" was related to sucrose content and sugar melting enthalpy. Tribological data provided meaningful information related to particle-derived attributes, as well as after-coating perception (fattiness/oiliness), thus better predicting food evolution during oral consumption.


Assuntos
Cacau , Corylus , Reologia , Paladar , Humanos , Viscosidade , Cacau/química , Boca/fisiologia , Tamanho da Partícula , Adulto , Feminino , Masculino , Saliva/química , Adulto Jovem
7.
J Texture Stud ; 55(4): e12851, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38952153

RESUMO

Rheological properties of gastric contents depend on the food ingested, and on the volume and composition of secretions from the host, which may vary. This study investigates the impact of saliva regular incorporation in the stomach after a meal on the rheological properties of gastric contents, considering two levels of salivary flow (low = 0.5 and high = 1.5 mL/min). In vitro chymes were obtained by mixing sour cream, simulated gastric fluid, two different volumes of oral fluid (at-rest human saliva, SSF for Simulated Salivary Fluid or water) and adjusting pH at 3. Chymes samples were characterized at 37°C for their particle size and rheological properties. Overall, particle size distribution was not different between samples: incorporating a larger volume of saliva resulted in more heterogeneity, but the surface area moment D[3,2] and volume moment D[4,3] did not differ significantly with the oral fluid type. Shear viscosity of chyme samples was higher when saliva was incorporated, in comparison with water or SSF. In addition, as shown from data extracted at γ ̇ $$ \dot{\gamma} $$ = 20 s-1 the higher the fluid volume the lower the shear viscosity, which is attributed to a dilution effect. However, this dilution effect was attenuated in the case of saliva, most likely due to its composition in organic compounds (e.g., mucins) contributing to the rheological properties of this biological fluid. In these in vitro conditions, both saliva and the salivation rate had a significant but slight impact on the rheological properties of gastric contents (of the order of 1-5 mPa s at γ ̇ $$ \dot{\gamma} $$ = 20 s-1).


Assuntos
Tamanho da Partícula , Reologia , Saliva , Saliva/química , Humanos , Viscosidade , Conteúdo Gastrointestinal/química , Concentração de Íons de Hidrogênio , Suco Gástrico/química
8.
PLoS One ; 19(7): e0302202, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38950007

RESUMO

It is structurally pertinent to understudy the important roles the self-compacting concrete (SCC) yield stress and plastic viscosity play in maintaining the rheological state of the concrete to flow. It is also important to understand that different concrete mixes with varying proportions of fine to coarse aggregate ratio and their nominal sizes produce different and corresponding flow- and fill-abilities, which are functions of the yield stress/plastic viscosity state conditions of the studied concrete. These factors have necessitated the development of regression models, which propose optimal rheological state behavior of SCC to ensure a more sustainable concreting. In this research paper on forecasting the rheological state properties of self-compacting concrete (SCC) mixes by using the response surface methodology (RSM) technique, the influence of nominal sizes of the coarse aggregate has been studied in the concrete mixes, which produced experimental mix entries. A total of eighty-four (84) concrete mixes were collected, sorted and split into training and validation sets to model the plastic viscosity and the yield stress of the SCC. In the field applications, the influence of the sampling sizes on the rheological properties of the concrete cannot be overstretched due to the importance of flow consistency in SCC in order to achieve effective workability. The RSM is a symbolic regression analysis which has proven to exercise the capacity to propose highly performable engineering relationships. At the end of the model exercise, it was found that the RSM proposed a closed-form parametric relationship between the outputs (plastic viscosity and yield stress) and the studied independent variables (the concrete components). This expression can be applied in the design and production of SCC with performance accuracies of above 95% and 90%, respectively. Also, the RSM produced graphical prediction of the plastic viscosity and yield stress at the optimized state conditions with respect to the measured variables, which could be useful in monitoring the performance of the concrete in practice and its overtime assessment. Generally, the production of SCC for field applications are justified by the components in this study and experimental entries beyond which the parametric relations and their accuracies are to be reverified.


Assuntos
Materiais de Construção , Reologia , Reologia/métodos , Materiais de Construção/análise , Viscosidade , Teste de Materiais/métodos , Previsões/métodos
9.
Sci Rep ; 14(1): 15493, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38969808

RESUMO

Dispersion of Basil seed gum has high viscosity and exhibits shear-thinning behavior. This study aimed to analyze the influence of microwave treatment (MT) at various time intervals (0, 1, 2, and 3 min) on the viscosity and rheological behavior of Basil seed gum dispersion (0.5%, w/v). The finding of this study revealed that the apparent viscosity of Basil seed gum dispersion (non-treated dispersion) reduced from 0.330 Pa.s to 0.068 Pa.s as the shear rate (SR) increased from 12.2 s-1 to 171.2 s-1. Additionally, the apparent viscosity of the Basil seed gum dispersion reduced from 0.173 Pa.s to 0.100 Pa.s as the MT time increased from 0 to 3 min (SR = 61 s-1). The rheological properties of gum dispersion were successfully modeled using Power law (PL), Bingham, Herschel-Bulkley (HB), and Casson models, and the PL model was the best one for describing the behavior of Basil seed gum dispersion. The PL model showed an excellent performance with the maximum r-value (mean r-value = 0.942) and the minimum sum of squared error (SSE) values (mean SSE value = 5.265) and root mean square error (RMSE) values (mean RMSE value = 0.624) for all gum dispersion. MT had a considerable effect on the changes in the consistency coefficient (k-value) and flow behavior index (n-value) of Basil seed gum dispersion (p < 0.05). The k-value of Basil seed gum dispersion decreased significantly from 3.149 Pa.sn to 1.153 Pa.sn (p < 0.05) with increasing MT time from 0 to 3 min. The n-value of Basil seed gum dispersion increased significantly from 0.25 to 0.42 (p < 0.05) as the MT time increased. The Bingham plastic viscosity of Basil seed gum dispersion increased significantly from 0.029 Pa.s to 0.039 Pa.s (p < 0.05) while the duration of MT increased. The Casson yield stress of Basil seed gum dispersion notably reduced from 5.010 Pa to 2.165 Pa (p < 0.05) with increasing MT time from 0 to 3 min.


Assuntos
Micro-Ondas , Ocimum basilicum , Gomas Vegetais , Reologia , Sementes , Ocimum basilicum/química , Sementes/química , Viscosidade , Gomas Vegetais/química
10.
Sci Rep ; 14(1): 15498, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38969829

RESUMO

Black liquor (BL) is the major bioproduct and biomass fuel in pulp mill processes. However, the high viscosity of BL makes it a challenging material to work with, resulting in issues with evaporators and heat exchangers during its transport and processing. The thermal and rheological properties of BLs from Pinus sp. (PBL) and Eucalyptus sp. (EBL) were studied. FTIR spectra revealed the presence of the characteristic functional groups and the chemical composition in liquors. TGA/DTG curves showed three characteristic degradation stages related to evaporation of water, pyrolysis of organic groups, and condensation of char. Rheologically, liquors are classified as non-Newtonian and with comportment pseudoplastic. Their rheological dynamic shear properties included a linear viscoelastic region up to 1% shear strain, while frequency sweeps showed that storage modulus (G') > loss modulus (G''), thus confirming the solid-like behavior of both BLs. The rheological study demonstrated that increasing the temperature and oscillatory deformations of PBL and EBL decreased their degree of viscoelasticity, which could favor their pumping and handling within the pulp mill, as well as the droplet formation and swelling characteristics in the recovery furnace.


Assuntos
Eucalyptus , Pinus , Reologia , Eucalyptus/química , Pinus/química , Viscosidade , Brasil , Finlândia , Temperatura , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Biomacromolecules ; 25(7): 4535-4544, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38973364

RESUMO

Recrystallization is considered the main damaging mechanism during the frozen storage of biologic materials. In this study, furcellaran, a polysaccharide related to κ-carrageenan, was studied for its concentration-dependent effect on ice crystal growth and recrystallization. The structure and sulfate content of the utilized furcellaran was analyzed by 1H nuclear magnetic resonance spectroscopy, ion chromatography, and high-performance size-exclusion chromatography. Additionally, the rheological properties of furcellaran solutions were investigated. Our findings demonstrate that furcellaran inhibits ice growth as effectively as κ-carrageenan. Furthermore, the rheological properties change with increasing furcellaran concentration, resulting in a gel-like consistency at 5 g/L, which coincides with decreased recrystallization inhibition activity and larger crystals. This suggests that gel formation or a gel-like consistency has to be avoided for optimal recrystallization inhibition activity.


Assuntos
Cristalização , Gelo , Reologia , Carragenina/química
12.
Bioinspir Biomim ; 19(5)2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38955342

RESUMO

This study investigates the role of leading-edge (LE) curvature in flapping wing aerodynamics considering hovering and forward flight conditions. A scaled-up robotic model is towed along its longitudinal axis by a rack gear carriage system. The forward velocity of the robotic model is changed by varying the advance ratioJfrom 0 (hovering) to 1.0. The study reveals that the LE curvature has insignificant influence on the cycle-average aerodynamic lift and drag. However, the time-history lift coefficient shows that the curvature can enhance the lift around the middle of downstroke. This enhanced lift is reduced from 5% to 1.2% asJchanged from 0 to 1.0. Further flow examinations reveal that the LE curvature is beneficial by enhancing circulation only at the outboard wing sections. The enhanced outboard circulation is found to emanate from the less stretched leading-edge vortices (LEVs), weakened trailing-edge vortices (TEVs), and the coherent merging of the tip vortices (TVs) with the minor LEVs as observed from the phase-lock planar digital particle image velocimetry measurements. The far-wake observation shows that the LE curvature enhances the vorticity within the TV, helping to reduce the overall flow fluctuations in the far field. These findings can be extended to explain the predominantly straight LE wing shape with a small amount of curvature only observed near the wing tip for flapping fliers with Re from 103to 104.


Assuntos
Simulação por Computador , Voo Animal , Modelos Biológicos , Robótica , Asas de Animais , Asas de Animais/fisiologia , Asas de Animais/anatomia & histologia , Voo Animal/fisiologia , Animais , Robótica/métodos , Biomimética/métodos , Fenômenos Biomecânicos , Reologia/métodos , Desenho de Equipamento
13.
Int J Mol Sci ; 25(13)2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-39000538

RESUMO

Skin penetration of an active pharmaceutical ingredient is key to developing topical drugs. This penetration can be adjusted for greater efficacy and/or safety through the selection of dosage form. Two emerging dosage forms, cream-gel and gel-in-oil emulsion, were tested for their ability to deliver diclofenac into the skin, with the target of maximising skin retention while limiting systemic exposure. Prototypes with varying amounts of solvents and emollients were formulated and evaluated by in vitro penetration testing on human skin. Cream-gel formulas showed better skin penetration than the emulgel benchmark drug even without added solvent, while gel-in-oil emulsions resulted in reduced diffusion of the active into the receptor fluid. Adding propylene glycol and diethylene glycol monoethyl ether as penetration enhancers resulted in different diclofenac penetration profiles depending on the dosage form and whether they were added to the disperse or continuous phase. Rheological characterisation of the prototypes revealed similar profiles of cream-gel and emulgel benchmark, whereas gel-in-oil emulsion demonstrated flow characteristics suitable for massaging product into the skin. This study underlined the potential of cream-gel and gel-in-oil emulsions for adjusting active penetration into the skin, broadening the range of choices available to topical formulation scientists.


Assuntos
Administração Cutânea , Diclofenaco , Emulsões , Absorção Cutânea , Pele , Diclofenaco/farmacocinética , Diclofenaco/administração & dosagem , Diclofenaco/química , Humanos , Absorção Cutânea/efeitos dos fármacos , Emulsões/química , Pele/metabolismo , Pele/efeitos dos fármacos , Reologia , Géis/química , Anti-Inflamatórios não Esteroides/farmacocinética , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Administração Tópica , Emolientes/química , Emolientes/farmacocinética , Emolientes/administração & dosagem
14.
Sci Rep ; 14(1): 16058, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992074

RESUMO

Estimating the tissue parameters of skin tumors is crucial for diagnosis and effective therapy in dermatology and related fields. However, identifying the most sensitive biomarkers require an optimal rheological model for simulating skin behavior this remains an ongoing research endeavor. Additionally, the multi-layered structure of the skin introduces further complexity to this task. In order to surmount these challenges, an inverse problem methodology, in conjunction with signal analysis techniques, is being employed. In this study, a fractional rheological model is presented to enhance the precision of skin tissue parameter estimation from the acquired signal from torsional wave elastography technique (TWE) on skin tumor-mimicking phantoms for lab validation and the estimation of the thickness of the cancerous layer. An exhaustive analysis of the spring-pot model (SP) solved by the finite difference time domain (FDTD) is conducted. The results of experiments performed using a TWE probe designed and prototyped in the laboratory were validated against ultrafast imaging carried out by the Verasonics Research System. Twelve tissue-mimicking phantoms, which precisely simulated the characteristics of skin tissue, were prepared for our experimental setting. The experimental data from these bi-layer phantoms were measured using a TWE probe, and the parameters of the skin tissue were estimated using inverse problem-solving. The agreement between the two datasets was evaluated by comparing the experimental data obtained from the TWE technique with simulated data from the SP- FDTD model using Pearson correlation, dynamic time warping (DTW), and time-frequency representation. Our findings show that the SP-FDTD model and TWE are capable of determining the mechanical properties of both layers in a bilayer phantom, using a single signal and an inverse problem approach. The ultrafast imaging and the validation of TWE results further demonstrate the robustness and reliability of our technology for a realistic range of phantoms. This fusion of the SP-FDTD model and TWE, as well as inverse problem-solving methods has the potential to have a considerable impact on diagnoses and treatments in dermatology and related fields.


Assuntos
Técnicas de Imagem por Elasticidade , Imagens de Fantasmas , Neoplasias Cutâneas , Técnicas de Imagem por Elasticidade/métodos , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/patologia , Humanos , Pele/diagnóstico por imagem , Pele/patologia , Reologia
15.
PLoS One ; 19(7): e0307113, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39008477

RESUMO

Understanding the extent of inflammation is crucial for early disease detection, monitoring disease progression, and evaluating treatment responses. Over the past decade, researchers have demonstrated the need to understand the extent of inflammation through qualitative or quantitative characterization of tissue viscoelasticity using different techniques. In this scientific review, an examination of research on the association between elasticity and Viscosity in diseases, particularly as tissue inflammation progresses, is conducted. A review of utilizing mechanical rheological models to characterize quantitative viscoelastic parameters of normal and inflamed tissues is also undertaken. Based on inclusion and exclusion criteria, we identified 14 full-text studies suitable for review out of 290 articles published from January 2000 to January 2024. We used PRISMA guidelines for the systematic review. In the review, three studies demonstrated the criterion used by the researchers in identifying the best rheological model. Eleven studies showed the clinical application of the rheological model in quantifying the viscoelastic properties of normal and pathological tissue. The review quantified viscoelastic parameters for normal and pathological tissue across various soft tissues. It evaluated the effectiveness of each viscoelastic property in distinguishing between normal and pathological tissue stiffness. Furthermore, the review outlined additional viscoelastic-related parameters for researchers to consider in future stiffness classification studies.


Assuntos
Elasticidade , Inflamação , Reologia , Viscosidade , Humanos , Inflamação/patologia , Modelos Biológicos
16.
PLoS One ; 19(7): e0298280, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39008482

RESUMO

Collagen-based membranes are class III-medical devices widely used in dental surgical procedures to favour bone regeneration. Here, we aimed to provide biophysical and biochemical data on this type of devices to support their optimal use and design/manufacturing. To the purpose, four commercial, non-crosslinked collagen-based-membranes, obtained from various sources (equine tendon, pericardium or cortical bone tissues, and porcine skin), were characterized in vitro. The main chemical, biophysical and biochemical properties, that have significant clinical implications, were evaluated. Membranes showed similar chemical features. They greatly differed in morphology as well as in porosity and density and showed a diverse ranking in relation to these latter two parameters. Samples highly hydrated in physiological medium (swelling-ratio values in the 2.5-6.0 range) and, for some membranes, an anisotropic expansion during hydration was, for the first time, highlighted. Rheological analyses revealed great differences in deformability (150-1500kPa G') also alerting about the marked variation in membrane mechanical behaviour upon hydration. Samples proved diverse sensitivity to collagenase, with the cortical-derived membrane showing the highest stability. Biological studies, using human-bone-derived cells, supported sample ability to allow cell proliferation and to prompt bone regeneration, while no relevant differences among membranes were recorded. Prediction of relative performance based on the findings was discussed. Overall, results represent a first wide panel of chemical/biophysical/biochemical data on collagen-based-membranes that 1) enhances our knowledge of these products, 2) aids their optimal use by providing clinicians with scientific basis for selecting products based on the specific clinical situation and 3) represents a valuable reference for optimizing their manufacturing.


Assuntos
Regeneração Óssea , Colágeno , Membranas Artificiais , Regeneração Óssea/efeitos dos fármacos , Colágeno/química , Colágeno/metabolismo , Animais , Humanos , Suínos , Porosidade , Cavalos , Proliferação de Células , Reologia
17.
Food Res Int ; 188: 114429, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823856

RESUMO

Among the emerging prebiotics, galactooligosaccharide (GOS) has a remarkable value with health-promoting properties confirmed by several studies. In addition, the application of ohmic heating has been gaining prominence in food processing, due to its various technological and nutritional benefits. This study focuses on the transformative potential of ohmic heating processing (OH, voltage values 30 and 60 V, frequencies 100, 300, and 500 Hz, respectively) in prebiotic chocolate milk beverage (3.0 %w/v galactooligosaccharide) processing. Chemical stability of GOS was assessed along all the ohmic conditions. In addition, microbiological analysis (predictive modeling), physical analysis (color and rheology), thermal load indicators assessment, bioactivity values, and volatile compound was performed. HPAEC-PAD analysis confirmed GOS stability and volatile compound evaluation supported OH's ability to preserve flavor-associated compounds. Besides, OH treatments demonstrated superior microbial reduction and decreased thermal load indicators as well as the assessment of the bioactivity. In conclusion, OH presented was able to preserve the GOS chemical stability on chocolate milk beverages processing with positive effects of the intrinsic quality parameters of the product.


Assuntos
Chocolate , Manipulação de Alimentos , Leite , Oligossacarídeos , Oligossacarídeos/química , Oligossacarídeos/análise , Chocolate/análise , Manipulação de Alimentos/métodos , Leite/química , Animais , Prebióticos/análise , Temperatura Alta , Bebidas/análise , Reologia , Cacau/química , Compostos Orgânicos Voláteis/análise
18.
Food Res Int ; 188: 114531, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823850

RESUMO

Different emulsion gel systems are widely applied to deliver functional ingredients. The effects and mechanisms of ultrasound-assisted emulsification (UAE) treatment and carboxymethyl cellulose (CMC) modifying the curcumin delivery properties and in vitro digestibility of the myofibrillar protein (MP)-soybean oil emulsion gels were investigated. The rheological properties, droplet size, protein and CMC distribution, ultrastructure, surface hydrophobicity, sulfhydryl groups, and zeta potential of emulsion gels were also measured. Results indicate that UAE treatment and CMC addition both improved curcumin encapsulation and protection efficiency in MP emulsion gel, especially for the UAE combined with CMC (UAE-CMC) treatment which encapsulation efficiency, protection efficiency, the release rate, and bioaccessibility of curcumin increased from 86.75 % to 97.67 %, 44.85 % to 68.85 %, 18.44 % to 41.78 %, and 28.68 % to 44.93 % respectively. The protein digestibility during the gastric stage was decreased after the CMC addition and UAE treatment, and the protein digestibility during the intestinal stage was reduced after the CMC addition. The fatty acid release rate was increased after CMC addition and UAE treatment. Apparent viscosity, storage modulus, and loss modulus were decreased after CMC addition while increased after UAE and UAE-CMC treatment especially the storage modulus increased from 0.26 Pa to 41 Pa after UAE-CMC treatment. The oil size was decreased, the protein and CMC concentration around the oil was increased, and a denser and uniform emulsion gel network structure was formed after UAE treatment. The surface hydrophobicity, free SH groups, and absolute zeta potential were increased after UAE treatment. The UAE-CMC treatment could strengthen the MP emulsion gel structure and decrease the oil size to increase the curcumin delivery properties, and hydrophobic and electrostatic interaction might be essential forces to maintain the emulsion gel.


Assuntos
Carboximetilcelulose Sódica , Curcumina , Digestão , Emulsões , Géis , Interações Hidrofóbicas e Hidrofílicas , Reologia , Curcumina/química , Emulsões/química , Carboximetilcelulose Sódica/química , Géis/química , Proteínas Musculares , Óleo de Soja/química , Viscosidade , Tamanho da Partícula , Miofibrilas/química , Miofibrilas/metabolismo , Ondas Ultrassônicas
19.
Food Res Int ; 188: 114474, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823865

RESUMO

Limited proteolysis, CaCl2 and carboxymethyl cellulose (CMC) have individually demonstrated ability to increase the gel strength of laboratory-extracted plant proteins. However, the syneresis effects of their combination on the gelling capacity of commercial plant protein remains unclear. This was investigated by measuring the rheological property, microstructure and protein-protein interactions of gels formed from Alcalase hydrolyzed or intact pea proteins in the presence of 0.1 % CMC and 0-25 mM CaCl2. Sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) showed the molecular weight of pea protein in the mixture were < 15 kDa after hydrolysis. The hydrolysates showed higher intrinsic fluorescence intensity and lower surface hydrophobicity than the intact proteins. Rheology showed that the storage modulus (G') of hydrolyzed pea protein (PPH)-based gels sightly decreased compared to those of native proteins. 5-15 mM CaCl2 increased the G' for both PP and PPH-based gels and decreased the strain in the creep-recovery test. Scanning electron microscopy (SEM) showed the presence of smaller protein aggregates in the PPH-based gels compared to PP gels and the gel network became denser, and more compact and heterogenous in the presence of 15 and 25 mM CaCl2. The gel dissociation assay revealed that hydrophobic interactions and hydrogen bonds were the dominant forces to maintain the gel structure. In vitro digestion showed that the soluble protein content in PPH-based gels was 10 âˆ¼ 30 % higher compared to those of the PP counterpart. CaCl2 addition reduced protein digestibility with a concentration dependent behavior. The results obtained show contrasting effects of limited proteolysis and CaCl2 on the gelling capacity and digestibility of commercial pea proteins. These findings offer practical guidelines for developing pea protein-based food products with a balanced texture and protein nutrition through formulation and enzymatic pre-treatment.


Assuntos
Cloreto de Cálcio , Carboximetilcelulose Sódica , Géis , Proteínas de Ervilha , Proteólise , Reologia , Cloreto de Cálcio/química , Proteínas de Ervilha/química , Carboximetilcelulose Sódica/química , Géis/química , Interações Hidrofóbicas e Hidrofílicas , Digestão , Pisum sativum/química , Microscopia Eletrônica de Varredura , Hidrólise , Eletroforese em Gel de Poliacrilamida
20.
Food Res Int ; 188: 114511, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823884

RESUMO

This study investigated the relationship between rheological properties, sensory perception, and overall acceptability in healthy young and old groups for dysphagia thickened liquids. Unflavored (UTL) and flavored (FTLP) thickened liquids were prepared using tap water or pomegranate juice at 10 different viscosity levels. The rheological properties were then evaluated via syringe flow test and line spread test (LST). When the apparent viscosity levels of UTL and FTLP were similar, the syringe test and LST results were also similar, indicating consistent flow behavior. Sensory perception evaluations showed that the young group better distinguished viscosity differences between stages compared to the old group. Regarding overall acceptability, the old group preferred samples with higher apparent viscosity than the young group. Principal component analysis and k-means cluster analysis were used to explore correlations between variables and classify thickened liquids into four groups. This can serve the foundation for standardized texture grades of dysphagia thickened liquids, considering rheological characteristics and sensory profiles.


Assuntos
Transtornos de Deglutição , Reologia , Humanos , Viscosidade , Adulto Jovem , Feminino , Masculino , Adulto , Idoso , Paladar , Percepção Gustatória , Pessoa de Meia-Idade , Bebidas , Sucos de Frutas e Vegetais , Análise de Componente Principal , Voluntários Saudáveis
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