Effect of sugars and salts on rheological properties of Balangu seed (Lallemantia royleana) gum

Rheological and dielectric behavior of sodium carboxymethyl cellulose (NaCMC)/Ca2+ and esterified NaCMC/Ca2+ hydrogels: Correlating microstructure and dynamics with properties

Polyelectrolyte-based conductive hydrogels are being extensively explored for applications in energy storage and as electrode materials for batteries. We synthesized ionically crosslinked sodium carboxymethyl cellulose (NaCMC), esterified NaCMC, and Ca2+ doped esterified NaCMC hydrogels. This work aims to understand the effect of Ca2+ ions on the NaCMC and esterified NaCMC. FTIR, SEM, Rheology and EIS studies were performed to understand the structure and dynamics of hydrogels. Results confirmed that Ca2+ ions have an important role in determining the rheological and dielectric response of hydrogels. Power law behavior was observed in their rheological response with exponent (n) of 0.81 for G' and 0.76 for G″ of ionically crosslinked NaCMC, 5.38 for G' and 4.70 for G″ of esterified NaCMC, whereas, negative exponents -1.44 for G' and -1.10 for G″ of Ca2+ ion doped esterified NaCMC. Ionically crosslinked NaCMC hydrogels have relaxation times (τ) in the range of 8.9 × 10-5 s-2.8 × 10-5 s may be due to the formation of temporary dipoles by electrostatic bridge formations with dc conductivity of (0.1 S/cm-5 S/cm), whereas, esterified NaCMC showed relaxation times (10-3 s-8.9 × 10-5 s) with increasing ester crosslinks and dc conductivity of (0.05 S/cm-0.8 S/cm). Interestingly, Ca2+ ion doped esterified hydrogels showed multiple dielectric relaxations on Ca2+ ion addition with different relaxation times may be due to change in ionic environment. The understanding obtained from this work may be useful for designing tuneable hydrogels with optimum electrical and mechanical properties.

Gelling and rheological properties of a polysaccharide extracted from Ocimum album L. seed

In this study, a new polysaccharide was isolated from Ocimum album L. seed (OA), and its physicochemical and rheological properties were investigated. Ocimum album polysaccharide (OAP) was an acidic heteropolysaccharide with a molecular weight of 1935 kDa, and it was composed of five types of sugars: mannose (32.95 %), glucose (27.57 %), galactose (19.29 %), rhamnose, (15.96 %) and galacturonic acid (4.23 %). According to the results obtained from Huggins and Kraemer equations, the intrinsic viscosity was 6.9 dL/g in distilled water. The OAP solutions at a concentration between 0.1 and 1.5 %, showed shear-thinning behavior, and the Herschel-Bulkley and Cross models exhibited a high ability to describe the flow behavior of OAP solutions. The apparent viscosity of 1 % OAP solution was decreased in the presence of different concentrations of NaCl (0.1, 0.3, and 0.5 M), at different pHs (3-11), and in temperatures between 5 and 100 °C. Also, the pseudoplastic behavior was observed in all samples. In OAP solutions (0.1-1.5 %), the up and down curves in the shear stress-shear rate diagram did not coincide, which indicated time-dependent (thixotropic) behavior. Although, the thixotropic properties of 1 % OAP solution were weakened with adding NaCl (0.1-0.5 M) and at different pH (3-11). The results obtained from the dynamic oscillatory test showed that the OAP solutions at concentrations higher than 0.1 % had a gel-like behavior, and the viscoelastic moduli (G' and G″) were weakened in the presence of salt and with a change in pH. Also, in the temperature sweep test, the 1 % solution showed the behavior of thermally irreversible gels.

Biocompatibility of electrospun cell culture scaffolds made from balangu seed mucilage/PVA composites

Synthesis of Balangu (Lallemantia royleana) seed mucilage (BSM) solutions combined with polyvinyl alcohol (PVA) was studied for the purpose of producing 3D electrospun cell culture scaffolds. Production of pure BSM nanofibers proved to be difficult, yet integration of PVA contributed to a facile and successful formation of BSM/PVA nanofibers. Different BSM/PVA ratios were fabricated to achieve the desired nanofibrous structure for cell proliferation. It is found that the optimal bead-free ratio of 50/50 with a mean fiber diameter of ≈180 nm presents the most desirable scaffold structure for cell growth. The positive effect of PVA incorporation was approved by analyzing BSM/PVA solutions through physiochemical assays such as electrical conductivity, viscosity and surface tension tests. According to the thermal analysis (TGA/DSC), incorporation of PVA enhanced thermal stability of the samples. Successful fabrication of the nanofibers is verified by FT-IR spectra, where no major chemical interaction between BSM and PVA is detected. The crystallinity of the electrospun nanofibers is investigated by XRD, revealing the nearly amorphous structure of BSM/PVA scaffolds. The MTT assay is employed to verify the biocompatibility of the scaffolds. The cell culture experiment using epithelial Vero cells shows the affinity of the cells to adhere to their nanofibrous substrate and grow to form continuous cell layers after 72 h of incubation.

Polysaccharide extracted from Althaea officinalis L. root: New studies of structural, rheological and antioxidant properties

A water-soluble acidic polysaccharide (AOP-2) from Althaea officinalis L. root was isolated by water extraction and purified by ion exchange chromatography (Cellulose DEAE-52) and gel filtration (Sephadex G-200). The structure characteristics of AOP-2 was determined by gel permeation chromatography (GPC), high performance liquid chromatography (HPLC), fourier transform infrared (FT-IR), nuclear magnetic resonance (NMR) spectrum and gas chromatography-mass spectrometry (GC_MS). The results indicated that the AOP-2 was an acidic hetropolysaccharide with the molecular weight of 639.27 kDa. The AOP-2 composed of 51% galacturonic acid, 32.56% rhamnose, 12.73% glucose and 3.71% galactose. It could be found that the main backbone chain of AOP-2 consisted of →3)-α-D-GalpA-(1→, →3)-α-D-Rhap-(1→ and→3,4)-β-D-Galp-(1→ with branches of →4)-α-D-Rhap-(1→, →4)-α-D-Glcp-(1→ and α-D-Rhap-(1 → . Thermal analysis revealed that the AOP-2 had high thermal stability and according to the results obtained from XRD analysis, it had a semi-crystalline structure. The results of Steady-shear flow and dynamical viscoelasticity showed that AOP-2 solutions exhibited shear-thinning behavior with high viscosity and a weak gel-like behavior at concentrations above 1% in linear viscoelastic region. In addition, it showed relatively high antioxidant property.

Effects of the Hofmeister anion series salts on the rheological properties of Sesbania cannabina galactomannan

Sesbania cannabina galactomannan (2%) solutions added with strongly hydrated ions (Na₂CO₃, NaH₂PO₄, NaCl) and weakly hydrated ions (NaNO₃) at different ionic strengths were rheologically characterized. The four selected salts dramatically decreased the intrinsic viscosity of galactomannan solution in the following order of effectiveness: Na₂CO₃ < NaH₂PO₄ < NaCl < NaNO₃. This conforms effectively to the Hofmeister anion series. Moreover, salt addition increased the viscosity of galactomannan solution when the ionic strength was 1 mmol/kg, which related to an increased occurrence of intermolecular interactions. As increasing ionic strength, galactomannan chains may tend to contract or expand due to the presence of strongly or weakly hydrated ions, thereby decreasing the viscosity. These phenomena were demonstrated by zeta potential measurement and again observed in dynamic viscoelasticity measurement. Overall, this property can be used to manipulate the rheological properties of galactomannan in food gums to obtain gums of high quality for enhancing consumer goods.

The aplication of Pistacia khinjuk extract nanoemulsion in a biopolymeric coating to improve the shelf life extension of sunflower oil

In the present study, a hydroalcoholic extract of P. khinjuk was obtained by sonication method at 60°C for 50 min. The measurement revealed that the total phenolic content of the extract was 46.0 mg/g. The results showed that the extract has an antioxidant activity of 73.5% and 8.3 (µmol TE/g DW) in DPPH radical scavenging method and FRAP assay, respectively. Also, Balango (Lallemantia royleana) and Fenugreek (Trigonella foenum-graecum) seed gum and their composition (1:1) were used to prepare the nanoemulsion with P. khinjuk extract. The droplet mean size of nanoemulsions was ranged from 310.34 to 354.19 nm. The highest encapsulation efficiency was observed in Balango nanoemulsion. P. khinjuk extract nanoemulsion coating with Balango and TBHQ was added to sunflower oil at 200 and 100 ppm, respectively. During 24-day storage at 60°C, samples were investigated for peroxide, acid, and p-anisidine values at 4-day intervals. The results showed that oils containing nanoemulsion had the highest stability during storage. However, in all samples peroxide, acid and p-anisidine values increased but the rate of oxidation in samples containing both synthetic and natural antioxidants was slower than the control sample.

Gums from Indigenous Plants of Iran: A Review on Physicochemical, Rheological and Functional Properties

Background:

Recently, public interests have increased to study novel and vernacular polysaccharides due to their various uses, especially in food formulations as well as pharmaceuticals and herbal medicines. Plant-based gums are commercially produced from a large number of plants that include complex polysaccharides.

Scope and Approach:

he present study has summarized physicochemical, rheological and functional properties of tragacanth, basil seed and balangu gums from indigenous plants of Iran.

Conclusion:

The results of this review study demonstrate that the highlighted gums are commonly used as dietary fibers, thickening agents, emulsifiers, stabilizers and drug delivery agents. The general appearance of gums varies from dark-brown to whitish in color. At various concentrations, pH and ionic strengths, aqueous dispersions show great variations in their rheological behavior. In conclusion, industrial applications of these gums are possible as a result of their strong thickening properties. Additionally, significant surface activity and emulsification capacity enable their application in the food, pharmaceutical and/or cosmetic industries.

Influence of different salts on rheological and functional properties of basil (Ocimum bacilicum L.) seed gum

In this paper, the influence of a variety of salts (NaCl, CaCl₂, and KCl) at different concentrations (0, 0.1, 0.5 and 1% w/w) on rheological and functional properties of basil seed gum (BSG) were investigated. BSG produced a high viscosity solution with yield stress, which was a function of salt type and concentration. In all samples, viscosity decreased as the electrostatic interactions between the BSG chains altered by salts. Flow behavior index increased by salt addition, which shows BSG had weaker shear-thinning behavior and worse mouthfeel in the presence of salts. The viscoelasticity of BSG strongly influenced by the addition of salt type as well as concentration. Larger cations (Ca⁺²) shield the electrostatic interaction between BSG chains more strongly compared to smaller cations as they have larger hydrated radius. As a result divalent salts decreased the viscosity and viscoelasticity more significantly. Emulsion capacity improved by salts addition, especially at high concentrations of salts. The foam capacity increased in the presence of CaCl₂ and KCl increased foaming capacity of BSG. The results suggest that the addition of the different types of salt can alter or modify the rheological and functional properties of BSG, depending on the salt concentration.

Improvement of gluten-free bread and cake properties using natural hydrocolloids: A review

The main wheat component responsible for bread and cake quality is gluten. Celiac disease is an autoimmune digestive disease that is caused by the digestion of gluten, and the only treatment of this disease is a gluten-free diet. Various gluten-free formulations (composite and wheatless flours) have applied gums (as gluten substitutes) to mimic the viscoelastic properties of gluten. In the bakery products, gums have been used to improve dough performance, bread and cake characteristics, textural and sensorial quality, and extension the products shelf life. This paper reviews the effect of the most common and new hydrocolloids (balangu seed, wild sage seed, basil seed, cress seed, xanthan, guar, starch carrageenan, methylcellulose, carboxy methyl cellulose, hydroxyl propyl methyl cellulose, and locust bean gums) on the rheological, physicochemical, textural, and quality characteristics of gluten-free breads and cakes. Gums affect gelatinization and retrogradation of starch through a strong association of amylose with gum, resulting in a decrease in the retrogradation of starch. Gums addition increased volume and porosity of the breads and cakes and resulted in softer products.

Effect of common and new gums on the quality, physical, and textural properties of bakery products: A review

Hydrocolloids (gums) have a good functional characteristic such as emulsifying, gelling, solubility, and textural improvement. In the bakery products, hydrocolloids were used to improving dough performance, bread and cake characteristics, sensorial quality, and extension the products shelf life. Several studies reported the potential use of hydrocolloids in breads, biscuits, cakes, and pasta formulation. The present review summarized the effect of the most common and new hydrocolloids (xanthan, guar, Arabic, carrageenan, karaya, alginate, acacia, methylcellulose, carboxy methyl cellulose, hydroxyl propyl methyl cellulose, locust bean, balangu seed, wild sage seed, basil seed, and cress seed gums) on the rheological, physicochemical, textural, and quality characteristics of bakery products. Gums addition improved volume and porosity of the breads and cakes. Gums influence on the gelatinization and retrogradation of starch and decreased the retrogradation of starch. In the bakery products, hydrocolloids were used to improving mixing and increasing the shelf life of the products through moisture preservation and avoidance of syneresis in some frozen foods. This study summarized the influence of the most common and new hydrocolloids on the rheological, physicochemical, textural, and quality characteristics of bakery products. Addition of seeds gum to the breads, biscuits, cakes, and pasta formula led to an increase in the viscosity of the batter. Also, the firmness of bakery products showed that they became softer with increasing gum levels.

The effects of Plantago major seed gum on steady and dynamic oscillatory shear rheology of sunflower oil-in-water emulsions

The effects of Plantago major seed (PMS) gum on the rheological properties of the sunflower oil-based emulsions (steady shear flow and dynamic oscillatory rheology) were investigated. The results of steady shear flow experiments showed that the shear stress-shear rate, apparent viscosity-shear rate, and shear stress-time data were well fitted with Herschel-Bulkley, Carreau, and Tiu-Bogar models, respectively, and showed the highest R² and the lower root mean square error within different models. The strain and frequency sweep data indicated that all emulsions showed weak gel-like behavior, which showed stable interactions and entanglements in the emulsion structure. CoX-Merz rule was applied to investigate the relationship between complex viscosity (η*) and apparent viscosity (η_a ). In all emulsions containing PMS gum, η* > η _a and they did not obey from this rule.

PRACTICAL APPLICATIONS

The rheological properties of emulsion are critical features in stabilization of emulsion based products. The PMS gum can potentially be used in producing and stabilization of emulsion based products and effects of this gum on in oil in water emulsion can be useful in development of plant originated hydrocolloids in foods.

Shirazi balangu (Lallemantia royleana) seed mucilage: Chemical composition, molecular weight, biological activity and its evaluation as edible coating on beefs

In this study, Lallemantia royleana seed mucilage (LRSM) was extracted from whole seeds using hot-water extraction. The structural information (monosaccharide compositions and molecular weight analysis), chemical composition (moisture, protein, ash, fat and carbohydrate), biological activity (antimicrobial, total phenol content and antioxidant activity) and effect LRSM edible coating on population of microbial pathogens (total viable count (TVC), psychrotrophic bacteria, Escherichia coli, Staphylococcus aureus and fungi), chemical changes (thiobarbituric acid, peroxide value and pH) and sensory attributes (color, odor and total acceptability) of the beef slices at 4°C for 18days (0, 3, 6, 9, 12, 15 and 18) were determined. The LRSM had 76.74% carbohydrate, 3.86% protein, 9.92% ash and 9.48% moisture. LRSM is a high molecular weight (1.19×106Da) polysaccharide, composed of galactose (36.28%), arabinose (35.96%), rhamnose (15.18%), xylose (7.38%) and glucose (5.20%). The LRSM total phenolic content and antioxidant activity (IC50) were equal to 82.56±1.6μgGAE/mg and 528.54±0.35μg/ml, respectively. The results showed that, the beef shelf life based on TVC for samples control, LRSM, LRSM+1% AHEO, LRSM+1.5% AHEO, and LRSM+2% AHEO were 6, 9, 9, 12, and 15days, respectively. There was no significant difference between LRSM+1% AHEO and LRSM samples, but the TVC in first one had slight changes than LRSM. Compared to the control samples, LRSM extended the microbial shelf life, oxidative stability and sensorial acceptability of beef by 3, 6 and 6days, respectively.

Studies on the Physicochemical and Processing Properties of Tremella fuciformis Powder

Tremella fuciformis is edible and medicinal food since ancient times in China. In this article, the physicochemical and processing properties of Tremella fuciformis powder (TFS) and synergistic interaction with Lotus seed powder (LTS) in aqueous solution were investigated. The elemental compositions of TFS were 1.71 % N, 47.21 % O, 40.35 % C, 6.25 % H and 0.20 % S. Aspartic and Glutamic acids were the major amino acids in TFS for taken about 0.91 % and 1.12 %. TFS dispersion couldn’t form a gel structure at all selected concentrations until the ratio of TFS: LTS was 1:1 at a total concentration of 36 mg/mL. The network strength of TFS/LTS dispersions increased with the total powder concentrations increased during continuous heating from 25°C to 70°C. Gluten, amorphous and crystalline regions, and amorphous starch were observed in mixtures TFS/LTS compared with TFS. TFS/LTS had a more concavo-convex microstructure than TFS due to starch gelatinization in LTS.

Combined infrared-vacuum drying of pumpkin slices

Infrared-vacuum dehydration characteristics of pumpkin (Cucurbita moschata) were evaluated in a combined dryer system. The effects of drying parameters, infrared radiation power (204-272 W), system pressure (5-15 kPa), slice thickness (5 and 7 mm) and time (0-220 min) on the drying kinetics and characteristics of pumpkin slices were investigated. The vacuum pressure, lamp power and slice had significant effect on the drying kinetics and various qualities of the dried pumpkin. Moisture ratios were fitted to 10 different mathematical equations using nonlinear regression analysis. The quadratic equation satisfactorily described the drying behavior of pumpkin slices with the highest r value and the lowest SE values. The effective moisture diffusivity increased with power and ranged between 0.71 and 2.86 × 10(-9) m(2)/s. With increasing in infrared radiation power from 204 to 272 W, β-carotene content of dried pumpkins decreased from 30.04 to 24.55 mg/100 g. The rise in infrared power has a negative effect on the color changes (ΔE). The optimum condition was determined as power, 238W, pressure, 5 kPa and slice thickness, 5mm. These conditions resulted into dried pumpkin slices with maximum B-carotene retention.

Static Rheological Study of Ocimum basilicum Seed Gum

A rotational viscometer was used to investigate the effect of different sugars (sucrose, glucose, fructose and lactose, 1–4% w/w) and salts (NaCl and CaCl2, 0.1–1% w/w), on rheological properties of Basil seed gum (BSG). The viscosity was dependent on type of sugar and salt addition. Interactions between BSG gum and sugars improved the viscosity of solutions, whereas the viscosity of the BSG solutions decreased in the presence of salts. Power law model well-described non-Newtonian shear thinning behavior of BSG. The consistency index was influenced by the sugars and salts content. Addition of sucrose, glucose, lactose and salts to BSG led to increases in flow behavior index (less shear thinning solutions), whereas fructose increased shear thinning of solutions. Flow behavior index values of the power law model vary as follows: 0.43–0.49, 0.53–0.64, 0.21–0.26, and 0.57–0.67 for sucrose, glucose, fructose and lactose, respectively. The consistency coefficient (k) of BSG was affected by sugars and salts. It decreased from 0.14 to 0.09 Pa.sn with increasing CaCl2 from 0 to 4% w/w (20°C, 0.2% w/w BSG). The consistency coefficient values vary as follows: 0.094–0.119, 0.075–0.098, 0.257–0.484, and 0.056–0.074 for sucrose, glucose, fructose and lactose, respectively.

Effect of thermal and freezing treatments on rheological, textural and color properties of basil seed gum

Hydrocolloids are macromolecular carbohydrates that are added to many foodstuffs to achieve the appropriate rheological and textural properties and to prevent synersis or to increase the viscosity and stability of foodstuffs. In this study the effect of different thermal treatments (25, 50, 75, 100 and 121°C for 20 min) and freezing treatments (-18 and -25 °C for 24 h) on rheological, textural and color change of basil seed gum as a new source of hydrocolloids was investigated. The results demonstrated that basil seed gum solutions had desirable rheological and textural properties. Power law model well described non-newtonian pseudoplastic behavior of basil seed gum in all conditions. When the hydrocolloid samples were heated or frozen, increase in viscosity of basil seed gum solutions was observed. Hardness, adhesiveness and consistency of basil seed gel for control sample were 13.5 g, 16.79, 52.59 g.s, respectively and all increased after thermal treatments. The results revealed that basil seed gum has the excellent ability to stand against heat treatment and the highest hardness, adhesiveness and consistency value of gum gels were observed in sample treated at 121 °C for 20 min. In addition this gum gel has the good ability to stand against freeze-thaw treatment and its textural properties improved after freezing. Therefore, basil seed gum can be employed as a textural and rheological modifier in formulation of foods exposed to thermal and freezing temperatures.

Kinetics and Thermodynamics of Gum Extraction from Wild Sage Seed

Wild sage seed (Salvia macrosiphon) has practical amounts of gum with good functional properties. In this work, extraction of gum from wild sage seed was studied. Effect of pH, temperature and water/seed ratio on the kinetic and thermodynamic parameters and entropy, enthalpy and free energy of extraction were investigated. The maximum gum yield was 12.5% at 55°C for pH=7 and water/seed ratio 40:1. In this study, the experimental data were fitted to a mathematical model of mass transport and constants were obtained. The kinetic of wild sage seed gum extraction was found to be a first-order mass transfer model. Statistical results indicated that the model used in this study will be able to predict the gum extraction from wild sage seed. It is also found that ΔH and ΔS were positive and ΔG was negative indicating that the extraction process was spontaneous, irreversible and endothermic. The ΔH, ΔS and ΔG values were 0.52–14.99 kJ/mol, 6.3–52.2 J/mol K and 0.14–2.44 kJ/mol, respectively.

Modeling of extraction process of crude polysaccharides from Basil seeds (Ocimum basilicum l.) as affected by process variables

Basil seed (Ocimum basilicum L.) has practical amounts of gum with good functional properties. In this work, extraction of gum from Basil seed was studied. Effect of pH, temperature and water/seed ratio on the kinetic and thermodynamic parameters; entropy, enthalpy and free energy of extraction were investigated. The maximum gum yield was 17.95 % at 50 °C for pH=7 and water/seed ratio 30:1. In this study, the experimental data were fitted to a mathematical model of mass transfer and equations constants were obtained. The kinetic of Basil seed gum extraction was found to be a first order mass transfer model. Statistical results indicated that the model used in this study will be able to predict the gum extraction from Basil seed adequately. It also found that ΔH and ΔS were positive and ΔG was negative indicating that the extraction process was spontaneous, irreversible and endothermic. The ΔH, ΔS and ΔG values were 0.26-7.87 kJ/mol, 8.12-33.2 J/mol K and 1.62-4.42 kJ/mol, respectively.