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1.
Food Chem ; 463(Pt 1): 141165, 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39265407

RESUMEN

Due to the instability of anthocyanins, their application as natural colorants is limited. To improve their stability, anthocyanins extracted from sour cherry were copigmented with tannic acid at varying molar ratios. The optimal anthocyanin:copigment molar ratio was determined to be 1:0.25. Subsequently, both non-copigmented and copigmented anthocyanins (using the optimal tannic acid molarity) were spray-dried with either maltodextrin alone (T1 and T2) or a combination of maltodextrin and Persian gum (T3 and T4). The anthocyanin retention in T2 and T4 was approximately 53 % and 38 %, respectively, which were higher than in the non-copigmented samples. All powders demonstrated high encapsulation efficiency (>90.37 %). Stability tests on the anthocyanins conducted over 28 days indicated that light exposure had no effect on the reduction of anthocyanin content when maltodextrin was used. Thus, the copigmentation of anthocyanins with tannic acid, combined with encapsulation in maltodextrin, presents a promising method for producing a stable natural colorant.

2.
Food Sci Nutr ; 12(6): 4211-4222, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38873444

RESUMEN

The study focused on the impact of the insoluble fraction of Persian gum-sodium alginate and a blend of the insoluble fraction of Persian gum-sodium alginate (IFPG-Al) with whey protein isolate (WPI) on sprayed Ziziphus jujuba extract (JE) powder. The addition of whey protein led to powders with higher moisture (10%), higher solubility (99.19%), and lower powder yield (27.82%). The powders fabricated with WPI depicted the best protection of polyphenolic compounds (3933.4 mg/L) and the highest encapsulation efficiency activity (74.84%). Additionally, they had a higher T g (62.63°C), which indicates more stability of the powders during shelf life. The sphericity of the majority of the particles was noticeable in powders, but multi-sided concavities were visible in the protein-containing particles. Based on the particle size's results, IFPG-Al/WPI capsules fabricated relatively smaller particles (2.54 µm). It can be acknowledged that the presence of protein in particles can bring fruitful results by preserving valuable bioactive compounds.

3.
Sci Rep ; 14(1): 5511, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38448644

RESUMEN

Burning fossil fuels releases toxic gases into the environment and has negative effects on it. In this study, Persian gum@Graphene oxide (Pg@GO) was synthesized and used as a novel adsorbent for CO2 capture. The characterization of materials was determined through XRD, FTIR, FE-SEM, and TGA analysis. The operating parameters including temperature, Pressure, and adsorbent weight were studied and optimized by response surface methodology via Box-Behnken design (RSM-BBD). The highest amount of CO2 adsorption capacity was 4.80 mmol/g, achieved at 300 K and 7.8 bar and 0.4 g of adsorbent weight. To identify the behavior and performance of the Pg@GO, various isotherm and kinetic models were used to fit with the highest correlation coefficient (R2) amounts of 0.955 and 0.986, respectively. The results proved that the adsorption of CO2 molecules on the adsorbent surface is heterogeneous. Based on thermodynamic results, as the value of ΔG° is - 8.169 at 300 K, the CO2 adsorption process is exothermic, and spontaneous.

4.
J Sci Food Agric ; 104(2): 892-904, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-37707173

RESUMEN

BACKGROUND: In the present study, the insoluble fraction of Persian gum (IFPG) was modified with octenyl succinic anhydride (OSA) and its various properties were assessed. In addition, the effect of OSA-IFPG on the rheological and textural properties of dairy cream was investigated. RESULTS: Suitable conditions for achieving a degree of substitution (DS) of 0.023 were found at pH 9, IFPG concentration 4 wt%, OSA concentration 10 wt% and a temperature of 40 °C, within 120 min. The carbonyl group attachment in OSA-IFPG was also confirmed via Fourier transform infrared and H-nuclear magnetic resonance spectroscopy (1 H-NMR). While the X-ray diffraction test indicated no significant changes in the structure of the IFPG after modification with OSA, esterification increased the negative charge density, decreased thermal decomposition temperature and increased the emulsifying capacity to 100%, which was obtained for the first time. The use of OSA-modified IFPG in creams augmented the complex viscosity, loss and storage modulus, while also demonstrating the creation of a pseudo-gel network. The hardness and adhesiveness of the texture increased, which can be explained by the formation of a compact structure and reduced particle size. CONCLUSION: Overall, OSA-IFPG with hydrophilic and hydrophobic sections may function as an emulsifier and be recommended as a safe source of hydrocolloids for emulsion stability. It can also provide a positive physical structure when added to dairy cream, even if the fat concentration is lower than usual. © 2023 Society of Chemical Industry.


Asunto(s)
Almidón , Anhídridos Succínicos , Anhídridos Succínicos/química , Almidón/química , Emulsiones/química , Emulsionantes/química
5.
Foods ; 12(13)2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37444326

RESUMEN

In the present study, electrospun nanofiber mats were fabricated by mixing different ratios (96:4, 95:5, 94:6, 93:7, and 92:8) of Persian gum (PG) and poly (ethylene oxide) (PEO). The SEM micrographs revealed that the nanofibers obtained from 93% PG and 7% PEO were bead-free and uniform. Therefore, it was selected as the optimized ratio of PG:PEO for the development of antimicrobial nanofibers loaded with ɛ-Polylysine (ɛ-PL). All of the spinning solutions showed pseudoplastic behavior and the viscosity decreased by increasing the shear rate. Additionally, the apparent viscosity, G', and G″ of the spinning solutions increased as a function of PEO concentration, and the incorporation of ɛ-PL did not affect these parameters. The electrical conductivity of the solutions decreased when increasing the PEO ratio and with the incorporation of ɛ-PL. The X-ray diffraction (XRD) and Fourier-transform infrared (FTIR) spectra showed the compatibility of polymers. The antimicrobial activity of nanofibers against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was investigated, and the samples loaded with ɛ-PL demonstrated stronger antimicrobial activity against S. aureus.

6.
Gels ; 9(6)2023 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-37367131

RESUMEN

In this study, the influence of different levels (0.1, 0.2, and 0.3% w/w) of Persian gum or almond gum were incorporated into wheat starch, and their influences on water absorption, freeze-thaw stability, microstructure, pasting, and textural properties were investigated. The SEM micrographs revealed that the addition of hydrocolloids to starch leads to the formation of denser gels with smaller pores. The water absorption of starch pastes was improved in the presence of gums, and samples containing 0.3% almond gum had the highest water absorption. The rapid visco analyzer (RVA) data showed that the incorporation of gums significantly affected the pasting properties by increasing the pasting time, pasting temperature, peak viscosity, final viscosity, and setback and decreasing breakdown. In all the pasting parameters, the changes caused by almond gum were more obvious. Based on TPA measurements, hydrocolloids were able to improve the textural properties of starch gels, such as firmness and gumminess but decreased the cohesiveness, and springiness was not affected by the incorporation of gums. Moreover, the freeze-thaw stability of starch was enhanced by the inclusion of gums, and almond gum exhibited better performance.

7.
Int J Biol Macromol ; 235: 123766, 2023 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-36841390

RESUMEN

The main purpose of this study is to synthesize and characterize Persian gum-based hydrogel composited with gentamicin (Gen)-loaded natural zeolite (Clinoptilolite) and to evaluate its biological properties. Clinoptilolite (CLN) was decorated with Gen, and the conjugation was confirmed using computational and experimental assessments. The Monte Carlo adsorption locator module was used to reveal the physicochemical nature of the adsorption processes of Gen on CLN and ALG and gum on Gen@ CLN in Materials Studio 2017 software. Based on the high negative results, the adsorption process was found to be endothermic in all studied cases, and the interaction energies were in the range of physisorption for Gen on CLN and ALG and gum on Gen@CLN. Dynamic light scattering (DLS) and zeta potential analysis showed that the size of pristine CLN was around 2959 nm and the conjugation decreased the size significantly to approximately 932 nm. The hydrogel characterizations showed that the Gen-decorated CLNs are homogenously dispersed into the hydrogel matrix, and the resultant hydrogels have a porous structure with interconnected pores. The release kinetics evaluation showed that around 80 % of Gen was released from the nanocomposite drug during the first 10 h. In vitro studies revealed hemocompatibility and cytocompatibility of the nanocomposite. Microbial assessments indicated dose-dependent antibacterial activity of the hydrogel against gram (+) and gram (-) bacteria. The results showed that the fabricated hydrogel nanocomposite exhibits favorable physicochemical and biological properties.


Asunto(s)
Gentamicinas , Zeolitas , Gentamicinas/farmacología , Gentamicinas/química , Hidrogeles/química , Antibacterianos/farmacología , Antibacterianos/química
8.
J Sci Food Agric ; 103(7): 3674-3684, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36799350

RESUMEN

BACKGROUND: This research was aimed at the fabrication of jujube extract (JE)-loaded beads by extrusion, using whey protein isolate (WPI), chickpea protein concentrate (PPC) and a combination of two types of hydrocolloid insoluble fraction of Persian gum (IFPG) and sodium alginate (Al). RESULTS: JE-loaded beads with the highest encapsulation efficiency (10.87%) and polyphenol content (120.8 mg L-1 gallic acid) were obtained using Al-IFPG/PPC at 4 °C. The Al-IFPG, Al-IFPG/WPI and Al-IFPG/PPC beads revealed 5.66, 6.85 and 5.76 mm bead size, respectively, and almost all of them demonstrated a homogeneous and spherical structure. Fourier transform infrared spectroscopy data proved that the stable structure of the Al-IFPG beads was due to hydrogen bonding and electrostatic interactions. The thermostability of beads loaded with JE based on Al-IFPG/WPI was significantly enhanced compared to pure Al-IFPG. Texture evaluation of JE-loaded beads based on Al-IFPG incorporation with WPI revealed an increment in the hardness of beads. CONCLUSION: This study confirmed the potential of Al-IFPG complex beads for the effective delivery of jujube extract via incorporation into pea and whey proteins and for the expansion of its use in products. © 2023 Society of Chemical Industry.


Asunto(s)
Proteínas de Guisantes , Ziziphus , Alginatos/química , Proteína de Suero de Leche/química
9.
Int J Biol Macromol ; 229: 746-751, 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36596371

RESUMEN

The application of edible films in food packaging is limited due to their poor functional properties. Cold plasma treatment (CPT) is an emerging technology for the modification of edible films. In this study, edible films were developed from different ratios of wild almond protein isolate (WAPI) and Persian gum (PG). The characterization of films revealed that the sample containing 90 % WAPI and 10 % PG had the highest elongation at break (E), the highest tensile strength (TS), and the lowest water vapor permeability (WVP). Therefore, it was selected as having the best WAPI:PG ratio and exposed to CPT for 5, 10, and 15 min. The results revealed that the application of CPT significantly increased the thickness, TS, and E of edible films, while WVP and solubility were not affected. FTIR spectra showed slight increases in peak intensities at 1628, 1538, and 1400 cm-1. The micrographs revealed that the roughness of composite films increased with increased cold plasma treatment time. In general, edible films treated by CPT for 10 min demonstrated the best functional properties.


Asunto(s)
Gases em Plasma , Prunus dulcis , Permeabilidad , Resistencia a la Tracción , Solubilidad , Embalaje de Alimentos , Vapor
10.
Int J Biol Macromol ; 223(Pt A): 1257-1267, 2022 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-36368364

RESUMEN

This study aimed to optimize the formulation of gluten-based composite film incorporated with Persian gum and Guar gum using the response surface method. The effects of three variables gluten (37%wt), Persian gum (1-2%wt), and guar gum (1-2%wt) on the physicochemical properties of the films (thickness, color parameters (L*, ΔE, WI, YI), swelling, solubility, water vapor permeability (WVP) and mechanical properties of the film were investigated. The results confirmed that gluten is compatible with Persian gum and Guar gum. Optimization was determined, and then the morphological properties and interaction of the film components were investigated with SEM and FTIR, respectively. Results showed that all three variables significantly affected the films' mechanical and physical properties (P < 0.05). Increasing the number of gums in the film solution led to a decrease in the thickness of the films, and improved solubility and WVP of films. Moreover, the yellowness index of films raised with an increasing amount of gluten and Guar gum. Increasing the number of gums, Young's modulus and modulus of elasticity decreased significantly (P < 0.05). The optimum level of the variables with desirability of 0.992, obtained by the software, was 5 % gluten, 1.5 % Persian gum, and 1.5 % Guar gum (% w/w). Intensifying and shifting some absorption peaks of FTIR spectra pattern confirmed the interaction of gums and gluten chain functional groups. The current research outcomes demonstrated that proper interaction was established between gluten protein and gums and improved the physical properties of the films. High amounts of gum reduced the thickness of the film.


Asunto(s)
Glútenes , Gomas de Plantas , Gomas de Plantas/química , Galactanos/química , Mananos/química , Solubilidad , Permeabilidad , Fenómenos Físicos , Vapor
11.
Int J Biol Macromol ; 209(Pt A): 1402-1409, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35461869

RESUMEN

Biocompatible electrospun nanofiber scaffolds were fabricated in this study using Persian gum (PG) and poly (vinyl alcohol) (PVA) to build an artificial extracellular matrix for cell growth. The preparation procedure involves mixing various ratios of PG/PVA to be electrospun and seeded with L929 fibroblasts. Upon addition of PG up to 60% to the solutions, a 30% decrease to around 240 µs·cm-1 is found in electrical conductivity which is in the range of semi-conductive polymers, whereas the surface tension is increased to around 3%. The fabricated scaffolds were characterized by morphological, chemical, thermal and structural analyses including SEM, FTIR spectroscopy, DSC, XRD, and tensile stress. The results showed that incorporation of 50% PG to the polymer solutions causes the formation of nanofibers with the least bead-shaped segments. All ratios of nanofibers containing PG showed significant biocompatibility with the cultured cells, which is presumably due to the radical scavenging feature of PG. The MTT and SEM analyses demonstrated that the scaffolds containing 50% PG possess the optimal cell compatibility, adhesion and proliferation properties. The fabricated PG/PVA cell culture scaffolds are potentially appropriate for wound dressing and cell culture applications in biomedicine.


Asunto(s)
Nanofibras , Técnicas de Cultivo de Célula , Nanofibras/química , Polímeros , Alcohol Polivinílico/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química
12.
Food Chem ; 362: 130040, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34087712

RESUMEN

This study aimed at the fabrication of licorice extract (LE)-loaded microparticles by complex coacervation, using chickpea protein isolate (CPI) and soluble fraction of Persian gum (SFPG). The LE-loaded microparticles with the highest encapsulation efficiency (97.87%) and loading capacity (11.35%) were obtained at pH 3 and CPI: SFPG ratio, core: coating ratio, and polymer concentration of 2, 1.5, and 2, respectively. The LE-loaded microparticles (2-15 µm) possessed heterogeneous microstructure, and the Fourier-transform infrared spectroscopy data confirmed the pronounced effect of electrostatic interactions and hydrogen bonding. The thermostability, amorphous structure, and color of the LE-loaded microparticles were significantly enhanced, compared to free LE. The sensory evaluation of the model beverages containing LE-loaded microparticles revealed that the microencapsulation was able to mask the bitter aftertaste and color of the extract. Thus, the results of this research confirm the potential of CPI-SFPG complex coacervates for the efficient delivery of glycyrrhizin via incorporation into functional food products.


Asunto(s)
Cicer , Alimentos Funcionales , Glycyrrhiza , Extractos Vegetales , Gomas de Plantas , Proteínas de Plantas , Raíces de Plantas , Prunus dulcis , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad Estática
13.
Prev Nutr Food Sci ; 26(1): 82-91, 2021 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-33859963

RESUMEN

Natural preservatives with high level of phenolic compounds, antioxidants and antimicrobial activities are used in mayonnaise to improve quality and safety due to their potential health benefits. Application of these compounds in production processes highlights many difficulties due to instability of their physical and chemical properties. Microencapsulation is used to address these restrictions. In this study, phenolic compounds from lemon waste were encapsulated with Persian gum (PG) and basil seed gum (BSG) as coating materials at different ratios (0:1, 1:0, and 1:1) at 15% (w/w) total biopolymer. We confirmed microencapsulation by scanning electron microscopy, and evaluate phenolic content, antioxidant activity, encapsulation efficiency, morphology, water solubility indexes, and water absorption indexes. Sample mayonnaise was prepared using microencapsulated polyphenols from lemon waste and extract (1,000 ppm of concentration), and control samples without extracts or microcapsules. All samples were subjected to chemical (measuring the peroxide, thiobarbituric acid, acidity, and color) and microbial (total count of microorganisms and Escherichia coli) analysis during 30 days of storage. BSG samples exhibited the highest antioxidant activity (61.19%) and encapsulation efficiency (70.72%), and PG/BSG microcapsules had the highest capability to prevent oxidative deterioration during storage. Addition of microcapsules led to increases in parameter b* and decreases in parameters a* and L*. In general, PG/BSG microcapsules were considered optimal samples for production of mayonnaise, since they prevented mayonnaise deterioration and exhibited antioxidant and antimicrobial properties.

14.
Polymers (Basel) ; 13(2)2021 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-33440825

RESUMEN

In the last decades, berries have been identified as important vehicles for the transmission of foodborne viruses and different strategies are being explored to eliminate or reduce viral contamination in these fruits. The aim of this work was to develop novel edible coatings with antiviral properties for inactivating and reducing murine norovirus (MNV). Firstly, the effect of gelatin (G) addition on Persian gum (PG) films was studied in terms of microstructural, mechanical, optical, and water barrier properties. The following PG:G ratios were considered: 100:0, 75:25, 50:50, 25:75, and 0:100. Microstructure analysis revealed the compatibility of both hydrocolloids since no phase separation was observed. The addition of G to PG films provided stiffer and more deformable films than pure PG, with lower water vapor permeability values. Specifically, films prepared with 50:50 PG:G ratio presented better mechanical and barrier performance. Interestingly, pure PG showed antiviral activity on murine norovirus, probably due to the presence of some impurities (mainly tannins). Adding allyl isothiocyanate (AITC) enhanced the PG antiviral activity at refrigerated temperatures in blueberries, not being affected by the AITC concentration. This effect was not observed at ambient temperature, probably due to the volatilization of AITC.

15.
Food Res Int ; 137: 109689, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33233264

RESUMEN

Crustacean byproducts are valuable sources of astaxanthin. In this study, an astaxanthin-rich lipid phase was extracted from shrimp waste and encapsulated in multilayer emulsions. Stabilized by electrostatic complexes of whey protein isolate (WPI) and Persian gum (PG), the multilayer emulsions were created by different WPI:PG mixing ratios (1:2-1:4). The resultant emulsions were then exposed to lyophilization. The encapsulation efficiency of astaxanthin in lyophilized powders was 42.9-49.8 (g astaxanthin/100 g astaxanthin). The moisture content and water activity of the powders decreased significantly (p < 0.05), but their solubility and hygroscopicity increased significantly (p < 0.05) in response to an increase in the PG content of the mixture (or by reducing the WPI:PG ratio). Morphological characterizations revealed the formation of smaller and more uniform microcapsules when higher amounts of PG were used. Water dispersibility was higher than 94 (g powder/100 g powder). The results of an accelerated stability test showed an improvement in astaxanthin chemical stability in the multilayer emulsions, particularly when the WPI:PG ratio was 1:4. A model beverage consisting of water (89 g/100 g), sugar (10 g/100 g) and citric acid (1 g/100 g) was prepared and the potential application of astaxanthin microcapsules as a natural colorant was studied and compared with a synthetic colorant (E110) under the effect of light/darkness, temperature (4 and 25 °C) and time (0-60 d). The encapsulated lipid extract imparted a highly stable color to the product which was comparable to the effect of the synthetic colorant. However, the astaxanthin concentration was highly affected by time and partially affected by light and temperature.


Asunto(s)
Bebidas , Emulsiones , Solubilidad , Proteína de Suero de Leche , Xantófilas
16.
Carbohydr Polym ; 246: 116639, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32747274

RESUMEN

Persian gum as a newly introduced source of carbohydrate polymers obtained from the trunk and branches of wild almond trees of Zagros forests in Iran, has found wide applications in food and pharmaceutical industry owing to its unique structure. However, its behavior in soil environment is still unknown. This paper proposes application of Persian gum to stabilization process of a low plasticity clayey soil. A series of macro and micro scale tests including unconfined compression strength, direct shear test, scanning electron microscopy imaging, Stereo zoom microscopy, Brunauer, Emmett and Teller tests, thermal gravimetric analysis and Particle size analysis were conducted on soil stabilized with different amounts of Persian gum. All defined tests were also conducted on previously studied soil additives, xanthan and guar gums. The results confirm the successful performance of Persian gum in binding soil particles, pore filling, thermal stability, soil fluctuation and formation of large particles in comparison to common hydrocolloids.


Asunto(s)
Prunus dulcis/química , Suelo/química , Madera/química , Agricultura/métodos , Secuencia de Carbohidratos , Coloides , Galactanos/química , Humanos , Irán , Mananos/química , Gomas de Plantas/química , Polisacáridos Bacterianos/química , Reología , Suelo/clasificación , Viscosidad
17.
Heliyon ; 6(7): e04350, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32671261

RESUMEN

The aim of the present investigation was to explore the possibility of developing a fruit snack formulation based on dried fig powder and chocolate-coated. Dried Fig (Ficus carica L.) powder with a maximum particle size of 354 µm and the lowest compaction force was formulated as the core. Persian gum was prepared at the concentrations of 1.5, 2 and 2.5% and xanthan gum was prepared at the levels of 0.25, 0.39 and 0.54% as the middle layer to the coating of the core. Regarding rheological assessments, sugar-free chocolate containing 29.3% isomalt was selected for the coating of the outer chocolate shell in the entitled snack. Textural analysis showed that coating of the core with hydrocolloids decreased hardness and adhesiveness of the samples (p < 0.05). It was also observed that increasing the xanthan gum and Persian gum concentration led to the reduction of adhesiveness in the snacks (p < 0.05). Coating of cores with hydrocolloids resulted in lower thickness of the chocolate outer shell, as well (p < 0.05). Results of the sensory evaluation tests demonstrated that, the samples with hydrocolloid coating were the most preferred ones by the panelists.

18.
J Food Sci Technol ; 57(9): 3284-3294, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32728277

RESUMEN

A new type of biodegradable film was formulated and characterized when based on the water-soluble-phase of Persian gum (SPG). The edible film was formulated optimally by using different concentrations of SPG (2.0, 2.5, 3.0, 3.5 and 4%) and glycerol as plasticizer (25, 35, and 35% based on dried SPG). Further examinations involved evaluating the manufactured films in terms of the barrier and physical properties, mechanical qualities, optical indices, microstructural properties and Fourier transform. The results showed that the increase in SPG and plasticizer content caused increases in thickness, moisture uptake, water vapor permeability and density of films (p < 0.05). Water solubility increased in response to higher concentrations of glycerol but decreased by higher amounts of dry matter (p < 0.05). The highest levels of the tensile strength (59.95%) and elongation at break (40.3 MPa) were obtained by SPG (3.5%) + 35% glycerol treatment. The L*, a* and opacity values decreased, while there was an increase in the b* value, as a result of increasing the plasticizer content (p < 0.05). A reduction occurred in the L* value of films, while the a* and b* values increased when using higher amounts of dry matter (p < 0.05). By analyzing the samples with field emission scanning electron microscopy, no cracks were observed on films when the contents of glycerol and dry matter were higher than 30% and 2.5%, respectively. The findings demonstrated that creating edible films from SPG can be an effective approach to the production of edible films.

19.
Ultrason Sonochem ; 68: 105190, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32485628

RESUMEN

The present work evidently reports that ultrasonic depolymerization strongly enhanced complex coacervation between Persian gum (PG) and whey protein isolate (WPI). PG was sonicated at 60 °C, operating frequency of 20 kHz and nominal power output of 800 W for various times followed by mixing with WPI. Acid-induced interaction between the two biopolymers was studied by turbidity, light scattering, zeta potential and viscosity measurements over a wide pH range. Sonication of intact PG (IPG) for 10 min considerably reduced the molecular weight from 4.12 × 106 to 0.76 × 106 g/mol. Besides, ultrasonic fragmentation of water insoluble fraction of PG drove protein containing chains into the soluble phase. Sonicated PG (SPG) was shown to be more flexible with higher number of carboxyl groups available for electrostatic interaction with WPI, such that the complete neutralization did not occur even at protein to polysaccharide ratio of 50: 1. Additionally, scattered light intensity and viscosity measurements revealed two maxima in the pH ranges of 4.4-4.85 and 3.27-4.0, being highly intense for the gum sonicated for 10 min and longer. Considering the pH-behavior of WPI components, the former peak was related to interpolymer complex formation between ß-lactoglobulin and long chain fraction of SPG, while the latter was attributed to intrapolymer association of α-lactalbumin with the short chain oligosaccharides arising from ultrasonic degradation of PG.


Asunto(s)
Gomas de Plantas/química , Sonicación , Proteína de Suero de Leche/química , Concentración de Iones de Hidrógeno , Fenómenos Ópticos , Solubilidad , Proteína de Suero de Leche/aislamiento & purificación
20.
Ultrason Sonochem ; 52: 311-317, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30563796

RESUMEN

The present study introduces the ultrasonic modification of two Iranian native gum exudates, Persian gum (PG) and gum tragacanth (GT) for the first time. They were sonicated at a constant frequency of 20 kHz and temperature of 60 °C for various times (0, 2, 5, 10, 20, 30 and 40 min) and the changes in their molecular properties were investigated using oven drying, gel permeation chromatography-multiangle laser-light scattering (GPC-MALLS), rheometery and FTIR analysis. Results indicated that the soluble dry mass of both hydrocolloids was extensively enhanced (from less than 10% at time zero to more than 90% at the end of treatment time) by sonication. Moreover, the molecular weight and viscosity of gums dispersions were decreased with the increase of the treatment time. Fracture in polysaccharide chains was confirmed by analysis of the molecular weight parameters. Calculation of chain breaks and polydispersity index (PDI) revealed that scissions occurred at the backbone as well as the side branches. PG, owing to its higher molecular weight, displayed more extensive and faster degradation than GT. However, the chain rupture of GT was twice more than that of PG at the end of sonication time. The specific volume for gyration (SVg) and molecular density (ρ) showed that intact PG contains compactly packed molecules with greater number of cross-linked bonds compared to GT. Furthermore, the conformational changes into semi-flexible chains and worm-like coils were determined for both gums after 40 min sonication. Variation of the molecular density along with the results of FTIR analysis demonstrated that ultrasonication broke C-O-C bonds in both PG and GT leading to more flexible chains.


Asunto(s)
Tragacanto/química , Ondas Ultrasónicas , Conformación Molecular , Polisacáridos/química , Reología , Solubilidad , Temperatura , Agua/química
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