Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 44
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Mol Divers ; 27(5): 1957-1969, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36098859

RESUMO

The Ugi four-component condensation in diluted liposomal suspensions was used to prepare pectin-based submicron capsules. A set of isocyanides and aldehydes was used to optimize the synthesis of capsule shells. Modified sugar beet pectin was selected as a natural polymer with pronounced surface activity to create a capsule shell. At first, liposomal composition was optimized in order to select suitable conditions for capsule formation. Then, the wide set of capsules constructed on modified sugar beet pectin scaffold has been synthesized. The choice was determined by level of substitution degree and possible chemical diversity of the modified surface. Detailed characterization of products has been performed for polysaccharide particles with liposomal core prepared with various processing parameters (concentration, cross-linking components, the density of linkage). The chemical structure, average size, polydispersity index, morphology, stability, and cytotoxicity of obtained particles have been investigated in dependence on the shell content. The obtained submicrometer cross-linked capsules (220-240 nm) with controlled colloidal properties showed high stability and low toxicity. Thus, the proposed carriers have a great potential as sustained drug delivery systems for different administration routes.


Assuntos
Beta vulgaris , Pectinas , Pectinas/química , Beta vulgaris/química , Polímeros , Açúcares
2.
J Sci Food Agric ; 103(1): 255-263, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35859266

RESUMO

BACKGROUND: Knowledge about specific functional characteristics, such as viscosimetric, conductometric, tensiometric and structural properties of polysaccharide aqueous solutions is highly important in the successful and adequate application in food emulsion formulation. For the first time detailed characterization of sugar beet fibers aqueous solutions in comparison to high molecular weight (sugar beet pectin) and low molecular weight [octenyl succinic anhydride (OSA) maltodextrin] hydrocolloids/stabilizers was performed through viscometry, conductometry, tensiometry and component analysis. RESULTS: Sugar beet fibers and its water-soluble fraction were investigated. All sugar beet fiber samples showed substantial surface-active properties but different effect on the viscosity values of aqueous solutions. Sugar beet pectin had higher impact on aqueous solutions viscosity values compared to sugar beet fiber samples. Structural bonding between investigated polysaccharides were evaluated through conductometric measurements. Intermolecular linking and probable embedding of OSA maltodextrin molecules into the sugar beet fiber complex structure was detected in conductometric studies. The increased concentration of sugar beet fibers in the presence of sugar beet pectin led to the accelerated increase in specific conductivity values indicating effects of 'macromolecular crowding', intermolecular and intramolecular conformation changes and charge formation. CONCLUSIONS: Detailed characterization of sugar beet fibers provided scientific insight towards fundamental characteristics of sugar beet fiber aqueous solutions. The presented characteristics are particularly applicable in the field of food emulsion stabilization due to the presented surface-active properties of sugar beet fibers as well as specific characteristics of investigated multi-polysaccharide systems. © 2022 Society of Chemical Industry.


Assuntos
Beta vulgaris , Condutometria , Pectinas/química , Beta vulgaris/química , Anidridos Succínicos , Emulsões/química , Água/química , Fibras na Dieta , Açúcares
3.
J Sci Food Agric ; 103(8): 4131-4142, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36565301

RESUMO

BACKGROUND: Traditional soy protein gel products such as tofu, formed from calcium sulfate or magnesium chloride, have poor textural properties and water retention capacity. Soy glycinin (SG) is the main component affecting the gelation of soy protein and can be cross-linked with polysaccharides, such as sugar beet pectin (SBP), and can be modified by changing system factors (e.g., pH) to improve the gel's properties. Soy glycinin/sugar beet pectin (SG/SBP) complex double network gels were prepared under weakly acidic conditions using laccase cross-linking and heat treatment. The structural changes in SG and the properties of complex gels were investigated. RESULTS: Soy glycinin exposed more hydrophobic groups and free sulfhydryl groups at pH 5.0. Under the action of laccase cross-linking, SBP could promote the unfolding of SG tertiary structures. The SG/SBP complex gels contained 46.77% ß-fold content and had good gelling properties in terms of hardness 290.86 g, adhesiveness 26.87, and springiness 96.70 mm at pH 5.0. The T22 relaxation time had the highest peak, and magnetic resonance imaging (MRI) showed that the gel had even water distribution. Scanning electron microscopy (SEM) and confocal scanning laser microscopy (CLSM) indicated that the SG/SBP complex network structure was uniform, and the pore walls were thicker and contained filamentous structures. CONCLUSION: Soy glycinin/ sugar beet pectin complex network gels have good water-holding, rheological, and textural properties at pH 5.0. The properties of soy protein gels can be improved by binding to polysaccharides, with laccase cross-linked, and adjusting the pH of the solution. © 2022 Society of Chemical Industry.


Assuntos
Beta vulgaris , Pectinas , Pectinas/química , Proteínas de Soja/química , Beta vulgaris/química , Lacase/química , Polissacarídeos/metabolismo , Catálise , Géis/química , Água/metabolismo , Açúcares/metabolismo
4.
Crit Rev Food Sci Nutr ; : 1-21, 2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-35950527

RESUMO

In recent years, sugar beet pectin as a natural emulsifier has shown great potential in food and pharmaceutical fields. However, the emulsification performance depends on the molecular structure of sugar beet pectin, and the molecular structure is closely related to the extraction method. This review summarizes the extraction methods of pectin, structure characterization methods and the current research status of sugar beet pectin-stabilized emulsions. The structural characteristics of sugar beet pectin (such as degree of methylation, degree of acetylation, degree of blockiness, molecular weight, ferulic acid content, protein content, neutral sugar side chains, etc.) are of great significance to the emulsifying activity and stability of sugar beet pectin. Compared with traditional hot acid extraction method, ultrasonic-assisted extraction, microwave-assisted extraction, subcritical water-assisted extraction, induced electric field-assisted extraction and enzyme-assisted extraction can improve the yield of sugar beet pectin. At the same time, compared with harsh extraction conditions (too high temperature, too strong acidity, too long extraction time, etc.), mild extraction conditions can better preserve these emulsifying groups in sugar beet pectin molecules, which are beneficial to improve the emulsifying properties of sugar beet pectin. In addition, the interfacial self-assembly behavior of sugar beet pectin induced by the molecular structure is crucial to the long-term stability of the emulsion. This review provides a direction for extracting or modifying sugar beet pectin with specific structure and function, which is instructive for finding alternatives to gum arabic.

5.
Molecules ; 26(9)2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-34068822

RESUMO

The contribution of rheological properties and viscoelasticity of the interfacial adsorbed layer to the emulsification mechanism of enzymatic modified sugar beet pectin (SBP) was studied. The component content of each enzymatic modified pectin was lower than that of untreated SBP. Protein and ferulic acid decreased from 5.52% and 1.08% to 0.54% and 0.13%, respectively, resulting in a decrease in thermal stability, apparent viscosity, and molecular weight (Mw). The dynamic interfacial rheological properties showed that the interfacial pressure and modulus (E) decreased significantly with the decrease of functional groups (especially proteins), which also led to the bimodal distribution of particle size. These results indicated that the superior emulsification property of SBP is mainly determined by proteins, followed by ferulic acid, and the existence of other functional groups also promotes the emulsification property of SBP.


Assuntos
Beta vulgaris/química , Emulsões/química , Enzimas/metabolismo , Pectinas/metabolismo , Reologia , Adsorção , Difusão , Elasticidade , Cinética , Peso Molecular , Óleos/química , Tamanho da Partícula , Pressão , Espectroscopia de Prótons por Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termogravimetria , Fatores de Tempo , Viscosidade , Água/química
6.
Molecules ; 23(10)2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30308985

RESUMO

Concentrated coconut milk (CCM), a raw material from coconut products, is extremely unstable because of its high oil content (>30%). In this study, three model emulsions-primary emulsions stabilized by coconut proteins only, secondary emulsions stabilized by the conjugation of sugar beet pectin (SBP) and coconut protein, and laccase-treated secondary emulsions-were prepared to investigate the effects of different factors (coconut proteins, coconut proteins + SBP, laccase-treated emulsions) on the stability of model emulsions and the application of this method to real CCM. The stability of the emulsions was evaluated based on their interfacial tension, zeta potential, particle size distribution, rheological properties, and the assembly formation of SBP and coconut protein at the oil⁻water interface. Results showed that addition of SBP or laccase can increase the viscosity and reduce the interfacial tension of the emulsion, and the effect was concentration dependent. Zeta potential of the emulsion decreased with the increase of protein (from -16 to -32 mV) and addition of SBP (from -32 to -46 mV), and it was reduced when laccase was added (from -9.5 to -6.0 mV). The secondary emulsion exhibited the narrowest particle size distribution (from 0.1 to 20 µm); however, laccase-catalyzed secondary emulsions showed the best storage stability and no layering when the laccase content reached 10 U/100 g. Confocal laser scanning microscopy (CLSM) revealed that protein was adsorbed on the oil⁻water interface and SBP distributed in the continuous phase could undergo oxidative crosslinking by laccase. These results show that the stability of the concentrated emulsion can be effectively improved by adding SBP and laccase.


Assuntos
Beta vulgaris/química , Cocos/química , Emulsões/química , Lacase/farmacologia , Pectinas/farmacologia , Tamanho da Partícula , Reologia , Eletricidade Estática , Tensão Superficial , Fatores de Tempo
7.
J Sci Food Agric ; 96(13): 4449-56, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26841309

RESUMO

BACKGROUND: In this study, soy protein isolate/sugar beet pectin (SPI/SBP) emulsion gels were prepared through an enzymatic gelation process. The effects of emulsifier (SBP, SPI or SPI/SBP complex) and emulsification process on the microstructure, texture, breakdown properties and aroma release behavior of resulting emulsion gels were investigated. RESULTS: Oil emulsification by SBP/SPI complex resulted in a higher amount of emulsifier absorbing on the oil-water interface than by SBP and SPI alone, indicating that a more compact interfacial network was formed. Flocculation of oil droplets was observed and corresponding emulsion gels exhibited lower fracture force and strain when the oil was emulsified by SPI and SBP/SPI complex. Moreover, emulsion gels with small droplets produced a greater quantity of small fragments after mastication. However, microstructure did not have a significant effect on breakdown properties of emulsion gels. Headspace gas chromatography analysis showed that the release rate of ethyl butyrate before and after mastication was significantly lower in emulsion gel with more compact network, but the release of aroma compounds with higher hydrophobicity did not show a significant influence of the microstructure and texture of emulsion gel. CONCLUSION: This finding provides a useful application for designing semi-solid foods with desirable flavor perception. © 2016 Society of Chemical Industry.


Assuntos
Beta vulgaris/química , Emulsificantes/química , Aditivos Alimentares/química , Mastigação , Pectinas/química , Raízes de Plantas/química , Proteínas de Soja/química , Butiratos/análise , Butiratos/química , Caproatos/análise , Caproatos/química , Caprilatos/análise , Caprilatos/química , Fenômenos Químicos , Óleo de Milho/química , Emulsificantes/análise , Emulsões , Aditivos Alimentares/análise , Géis , Temperatura Alta , Humanos , Fenômenos Mecânicos , Odorantes , Tamanho da Partícula , Pectinas/análise , Sensação , Proteínas de Soja/análise , Propriedades de Superfície , Volatilização
8.
Int J Biol Macromol ; 275(Pt 1): 133643, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38964680

RESUMO

In this study, the effects of different ultrasonic treatment intensities (57, 170, and 283 W/cm2) on the chemical composition, molecular chain characteristics, crystal structure, micromorphology, interfacial adsorption behavior and emulsifying properties of sugar beet pectin (SBP) were investigated. Ultrasonic treatment did not change the types of SBP monosaccharides, but it had impacts on their various monosaccharide contents. Moreover, the feruloylated, acetyl, and methoxy groups of SBP also undergo varying degrees of changes. The increase in ultrasonic treatment intensity led to transition in the molecular chain conformation of SBP from rigid semi-flexible chains to flexible chains, accompanied by modification in its crystal structure. Microstructural analysis of SBP confirmed the significant change in molecular chain conformation. Modified SBP could form an elastic interfacial film with higher deformation resistance on the oil-water interface. The SBP sample modified with 170 W/cm2 exhibited better emulsifying properties owing to its better interfacial adsorption behavior. Moreover, the emulsions prepared with modified SBP exhibited better stability capability under different environmental stresses (pH value, salt ion concentration, heating temperature and freeze-thaw treatment). The results revealed that the ultrasonic technology is useful to improve the emulsifying properties of SBP.

9.
Carbohydr Polym ; 329: 121790, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38286557

RESUMO

Glycosylation is a method that enhances the functional properties of proteins by covalently attaching sugars to them. This study aimed at preparing three conjugates (WP-HG, WP-SBP, and WP-RGI) by dry heating method to research the influence of different pectin structures on the functional properties of WP and characterize properties and structures of these conjugates. The research results manifested that the degree of glycosylation (DG) of HG, SBP and RGI were 13.13 % ± 0.07 %, 23.27 % ± 0.3 % and 36.39 % ± 0.3 % respectively, suggesting that the increase of the number of branch chains promoted the glycosylation reaction. The formation of the conjugate was identified by the FT-IR spectroscopy technique. And SEM showed that WP could covalently bind to pectin, resulting in a smoother and denser surface of the conjugates. The circular dichroism analysis exhibited that the glycosylation reaction altered the secondary structure of WP and decreased the α-Helix content. This structural change in the protein spatial conformation led to a decrease in the hydrophobicity of protein surface. But the addition of pectin further regulated the hydrophilic-hydrophobic ratio on the surface of the protein, thus improving the emulsification properties of WP. In addition, the glycosylation could improve the stability of the emulsion, giving it a smaller droplet size, higher Zeta-potential and more stable properties. In a word, this study pointed out the direction for the application of different pectin structures in the development of functional properties of glycosylation products in food ingredients.


Assuntos
Pectinas , Proteínas do Soro do Leite/química , Pectinas/química , Glicosilação , Espectroscopia de Infravermelho com Transformada de Fourier , Emulsões/química
10.
ACS Appl Bio Mater ; 7(5): 3506-3514, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38696441

RESUMO

Horseradish peroxidase (HRP)-mediated hydrogelation, caused by the cross-linking of phenolic groups in polymers in the presence of hydrogen peroxide (H2O2), is an effective route for bioink solidification in 3D bioprinting. Sugar beet pectin (SBP) naturally has cross-linkable phenols through the enzymatic reaction. Therefore, chemical modifications are not required, unlike the various polymers that have been used in the enzymatic cross-linking system. In this study, we report the application of SBP in extrusion-based bioprinting including HRP-mediated bioink solidification. In this system, H2O2 necessary for the solidification of inks is supplied in the gas phase. Cell-laden liver lobule-like constructs could be fabricated using bioinks consisting of 10 U/mL HRP, 4.0 and 6.0 w/v% SBP, and 6.0 × 106 cells/mL human hepatoblastoma (HepG2) cells exposed to air containing 16 ppm of H2O2 concurrently during printing and 10 min postprinting. The HepG2 cells enclosed in the printed constructs maintained their viability, metabolic activity, and hepatic functions from day 1 to day 7 of the culture, which indicates the cytocompatibility of this system. Taken together, this result demonstrates the potential of SBP and HRP cross-linking systems for 3D bioprinting, which can be applied in tissue engineering applications.


Assuntos
Bioimpressão , Peroxidase do Rábano Silvestre , Pectinas , Impressão Tridimensional , Engenharia Tecidual , Humanos , Beta vulgaris/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/síntese química , Sobrevivência Celular/efeitos dos fármacos , Reagentes de Ligações Cruzadas/química , Células Hep G2 , Peroxidase do Rábano Silvestre/metabolismo , Peroxidase do Rábano Silvestre/química , Peróxido de Hidrogênio/química , Teste de Materiais , Tamanho da Partícula , Pectinas/química
11.
Food Chem ; 446: 138797, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38442678

RESUMO

This study investigated the effects of different matrices on gel properties, lipid digestibility, ß-carotene bioaccessibility, released free amino acids and gel network degradation. Microstructure studies have proven that sugar beet pectin/soy protein isolate-based emulsion-filled gel (SBP/SPI-E) with interpenetrating networks was formed. SBP/SPI-E exhibited higher hardness (2.67 N, p < 0.05) and released lesser free amino acids (269.48-µmol/g SPI) than soy protein isolate-based emulsion-filled gel (SPI-E) in simulated intestinal fluid (SIF); however, both had similar free amino acids contents in simulated colonic fluid. SBP has the potential to delay gel network degradation in SIF, as evidenced by the sugar stain strips of SDS-PAGE and microstructure observation. Furthermore, SBP/SPI-E and SPI-E exhibited similar ß-carotene bioaccessibility in SIF, suggesting that SBP from composite gel could not affect the aforementioned bioaccessibility. The study provides useful information for the design of functional gels in the application of fat-soluble nutrient delivery.


Assuntos
Pectinas , Proteínas de Soja , Emulsões/química , Proteínas de Soja/química , Pectinas/química , beta Caroteno , Géis/química , Aminoácidos , Açúcares
12.
Foods ; 12(14)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37509863

RESUMO

Research on the use of polysaccharides as hydrophobic bioactive carriers instead of proteins is still scarce. Sugar beet pectin (SBP) contains a small amount of protein and is a potential carrier for loading curcumin. In this work, SBP encapsulation, genipin crosslinking, and laccase-induced gelation were used to develop novel jelly food and improve the stability of curcumin without the incorporation of oil. By mixing the SBP solution (40 mg/mL) with curcumin powder (25 mg/mL SBP solution), an SBP-curcumin complex (SBP-Cur) was fabricated with a loading amount of 32 mg/g SBP, and the solubility of curcumin improved 116,000-fold. Fluorescence spectroscopy revealed that hydrophobic interactions drove the complexation of curcumin and SBP. Crosslinked by genipin (10 mM), SBP-Cur showed a dark blue color, and the gel strength of laccase-catalyzed gels was enhanced. Heating and UV radiation tests suggested that the genipin crosslinking and gelation strategies substantially improved the stability of curcumin. Because of the unique UV-blocking capacity of blue pigment, crosslinked samples retained 20% more curcumin than control samples. With the enhanced stability of curcumin, the crosslinked SBP-curcumin complexes could be a functional food ingredient used in functional drinks, baked food, and jelly food.

13.
Int J Biol Macromol ; 253(Pt 6): 127328, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37820921

RESUMO

The effects of addition of sugar beet pectin (SBP) on the pasting, rheological, thermal, and microstructural properties of wheat starch (WS) were investigated. Results revealed that SBP addition significantly increased the peak viscosity, trough viscosity, breakdown value, final viscosity, and setback value of WS, whereas decreased the pasting temperature. SBP raised the swelling power (from 13.44 to 21.32 g/g) and endothermic enthalpy (ΔH, from 8.17 to 8.98 J/g), but decreased the transparency (from 9.70 % to 1.37 %). Regarding rheological properties, WS-SBP mixtures exhibited a pseudo-plastic behavior, and SBP enhanced the viscoelasticity, but decreased the deformability. Particle size distribution analysis confirmed that SBP promoted the swelling of WS granules. Fourier-transform infrared spectroscopy results suggested that the interactions between SBP and WS did not involve covalent bonding, and the formation of ordered structure was inhibited by SBP addition. Additionally, scanning electron microscopy observation found that the gel network of WS-SBP mixtures became more irregular, pore size gradually decreased, and the wall became thinner as the SBP concentration increased. These results indicated that SBP is a promising non-starch polysaccharide that can enhance the processing properties of WS.


Assuntos
Beta vulgaris , Amido , Amido/química , Triticum/química , Pectinas , Viscosidade , Açúcares
14.
Carbohydr Polym ; 316: 121026, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37321724

RESUMO

Herein, we report the hydrogelation of sugar beet pectin (SBP) via visible light-mediated photocrosslinking and its applications in extrusion-based 3D bioprinting. Rapid hydrogelation (<15 s) was achieved by applying 405 nm visible light to an SBP solution in the presence of tris(bipyridine)ruthenium(II) chloride hexahydrate ([Ru(bpy)3]2+) and sodium persulfate (SPS). The mechanical properties of the hydrogel could be tuned by controlling the visible light irradiation time and concentrations of SBP, [Ru(bpy)3]2+, and SPS. High-fidelity 3D hydrogel constructs were fabricated by extruding inks containing 3.0 wt% SBP, 1.0 mM [Ru(bpy)3]2+, and 1.0 mM SPS. Human hepatoblastoma (HepG2) cells encapsulated in SBP hydrogels remained viable and metabolically active after 14 d of culture. Overall, this study demonstrates the feasibility of applying SBP and a visible light-mediated photocrosslinking system to the 3D bioprinting of cell-laden constructs for tissue engineering applications.


Assuntos
Beta vulgaris , Bioimpressão , Humanos , Pectinas , Hidrogéis , Luz , Açúcares
15.
J Agric Food Chem ; 70(26): 8052-8063, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35732030

RESUMO

Pickering stabilizers with additional antioxidant, photostabilizing, and metal-chelating properties are suitable for structuring multifunctional Pickering emulsion systems. Tannic acid (TA) is a potential material which when adsorbed onto the interface may impart antioxidant, UV-light-shielding, and chelating properties to Pickering stabilizers. Herein, we report a type of TA polyelectrolyte nanoparticles (NPs) fabricated following a complexation between TA and aminated sugar beet pectin (SBP-NH2). This study is geared toward investigating the performance of TA/SBP-NH2 NPs in stabilizing Pickering emulsions and protecting ß-carotene from degradation. TA/SBP-NH2 NPs formed under optimum conditions had a mean diameter of 82 nm with a sphere-like shape. Because of their favorable surface wettability (91.2°), TA/SBP-NH2 NPs promoted formation of the low-, medium-, and high-internal-phase Pickering emulsions (HIPEs) in an oil volume fraction (φ)-dependent manner; the TA/SBP-NH2 NP-stabilized HIPE demonstrated viscoelastic properties increasing with the increasing concentration (c) of nanoparticles. Due to the excellent storage stability and UV light-absorbing capacity, the photostability of ß-carotene was significantly improved by a TA/SBP-NH2 NP-stabilized HIPE (φ = 0.75; c = 3 mg/mL). Altogether, this study highlights that TA/SBP-NH2 NPs have potential applications in structuring Pickering emulsions with improved protective effects on loaded lipophilic compounds.


Assuntos
Beta vulgaris , Nanopartículas , Antioxidantes , Emulsões , Excipientes , Tamanho da Partícula , Pectinas , Açúcares , Taninos , beta Caroteno
16.
J Colloid Interface Sci ; 628(Pt A): 684-695, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35944299

RESUMO

HYPOTHESIS: A novel range of microgel particles of different internal cross-linking densities can be created by covalently cross-linking sugar beet pectin (SBP) with the enzyme laccase and mechanically breaking down the subsequent parent hydrogels to sugar beet pectin microgels (SBPMG) via shearing. The bulk rheological properties of suspensions of the different SBPMG are expected to depend on the microgel morphology, elasticity (crosslinking density) and volume fraction respectively. EXPERIMENTS: The rheology of both dilute and concentrated dispersions of SBPMG were studied in detail via capillary viscometry and shear rheometry, supplemented by information on particle size and shape from static light scattering, confocal microscopy and electron microscopy. FINDINGS: For dilute suspensions of SBPMG, data for viscosity versus effective volume fraction (ɸeff) falls on a 'master' curve for all 3 types of SBPMG. In the more concentrated regime, the softer microgels allow greater packing and interpenetration and give lower viscosities at the same ɸeff, but all 3 types of microgel give much higher viscosities than the equivalent concentration of 'non-microgelled' pectin. The firmer microgels can be concentrated to achieve elasticities equivalent to the original parent hydrogel. All SBPMG suspensions were extremely shear thinning but showed virtually no time-dependence.


Assuntos
Microgéis , Pectinas , Hidrogéis , Lacase , Reologia , Açúcares
17.
Foods ; 11(16)2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-36010392

RESUMO

Pectin is a potential polysaccharide-based emulsifier, but the stabilized emulsions suffer from insufficient emulsion stability. Therefore, modification is needed to enhance its emulsification performance to cater to practical applications. The genipin-crosslinking strategy was used in this work to modify pectin with different sources and extraction conditions. Chemical composition analysis, molecular weight (Mw), and radius of gyration (Rg) measurement revealed that sugar beet pectin (SBP) has a more compact and flexible conformation than commercial citrus pectin (CP) and apple pectin (AP), indicated by the significantly (p < 0.05) larger Mw/Rg of SBP (18.1−11.3 kg/mol/nm) than CP (8.3 kg/mol/nm) and AP (8.0 kg/mol/nm). Crosslinking modification significantly increased the Mw, radius of gyration, and viscosity. This significantly (p < 0.05) improved the emulsifying stability (a smaller increase in droplets size) by the contribution of both thicker adsorbed hydrated layers at the oil-water interface with a stronger steric-hindrance effect and larger viscosity effect to slow down droplet collision. The formation of a blue-black substance from crosslinking reaction was able to block the UV radiation, which significantly improved the photostability of ß-carotene-loaded emulsions. Altogether, genipin-crosslinking is feasible to modify pectin of different sources to enhance the emulsion stability and for use as a vehicle for delivering bioactive compounds.

18.
Foods ; 11(2)2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35053946

RESUMO

The influence of the conformation of sugar beet pectin (SBP) on the interfacial and emulsifying properties was investigated. The colloidal properties of SBP, such as zeta potential and hydrodynamic diameter, were characterized at different pH levels. Furthermore, pendant drop tensiometry and quartz crystal microgravimetry were used to study adsorption behavior (adsorbed mass and adsorption rate) and stabilizing mechanism (layer thickness and interfacial tension). A more compact conformation resulted in a faster reduction of interfacial tension, higher adsorbed mass, and a thicker adsorption layer. In addition, emulsions were prepared at varying conditions (pH 3-5) and formulations (1-30 wt% MCT oil, 0.1-2 wt% SBP), and their droplet size distributions were measured. The smallest oil droplets could be stabilized at pH 3. However, significantly more pectin was required at pH 3 compared to pH 4 or 5 to sufficiently stabilize the oil droplets. Both phenomena were attributed to the more compact conformation of SBP at pH < pKa: On the one hand, pectins adsorbed faster and in greater quantity, forming a thicker interfacial layer. On the other hand, they covered less interfacial area per SBP molecule. Therefore, the SBP concentration must be chosen appropriately depending on the conformation.

19.
Foods ; 12(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36613300

RESUMO

A bacon-type meat analogue consists of different structural layers, such as textured protein and a fat mimetic. To obtain a coherent and appealing product, a suitable binder must glue those elements together. A mixture based on pea protein and sugar beet pectin (r = 2:1, 25% w/w solids, pH 6) with and without laccase addition and a methylcellulose hydrogel (6% w/w) serving as benchmark were applied as binder between textured protein and a fat mimetic. A tensile strength test, during which the layers were torn apart, was performed to measure the binding ability. The pea protein-sugar beet pectin mixture without laccase was viscoelastic and had medium and low binding strength at 25 °C (F ≤ 3.5 N) and 70 °C (F ≈ 1.0 N), respectively. The addition of laccase solidified the mixture and increased binding strength at 25 °C (F ≥ 4.0 N) and 70 °C (F ≈ 2.0 N), due to covalent bonds within the binder and between the binder and the textured protein or the fat mimetic layers. Generally, the binding strength was higher when two textured protein layers were glued together. The binding properties of methylcellulose hydrogel was low (F ≤ 2.0 N), except when two fat mimetic layers were bound due to hydrophobic interactions becoming dominant. The investigated mixed pectin-pea protein system is able serve as a clean-label binder in bacon-type meat analogues, and the application in other products seems promising.

20.
Int J Biol Macromol ; 182: 252-263, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33838198

RESUMO

Food-grade Pickering high internal phase emulsions (HIPEs) stabilized by a mixture of ß-cyclodextrin (ß-CD) and sugar beet pectin (SBP) were fabricated for the first time. The factors affecting the microstructures, mechanical properties, and stabilities of the Pickering HIPEs were systematically investigated. The corresponding hybrid particles were also separated and characterized to reveal the formation mechanism. The results indicated that the mixture could induce the formation of HIPEs with an oil phase volume fraction (φ) of 75% using a one-step high-speed shearing process at room temperature. The composition (the mass ratio of ß-CD to SBP, Rc/s) and concentration (W) of the mixture had significant effects on the formation and properties of HIPEs. When W ≥ 1.0% and Rc/s = 2:2 or 3:1, HIPEs had smaller oil droplets, higher gel strengths, better centrifugation stabilities and lutein protection effects. The spectral analysis suggested that SBP could adhere to the surface of ß-CD particles to form hybrid particles during the homogenization. Compared with native ß-CD particles, these hybrid particles had higher ζ-potential absolute values, and the SBP could also increase the viscosity of the aqueous phase, which contributed to the formation and properties of these HIPEs.


Assuntos
Emulsões/química , Pectinas/química , beta-Ciclodextrinas/química , Beta vulgaris/química , Emulsificantes/química , Alimentos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA