Addition Of Guar Gum Research Articles

Influence of the addition of hydrocolloids on the thermal, pasting and structural properties of starch from common vetch seeds (Vicia sativa sp)

Belonging to the leguminous family, the common vetch seeds are a non-conventional starch source that can be exploited to attend the growing demand of the food industry. Thus, the aim of this study was to evaluate the influence of addition of hydrocolloids (5% of: carrageenan, carboxymethylcellulose (CMC), guar, jatahy, xanthan and pectin) on the thermal, pasting and structural properties of starch from common vetch (Vicia sativa) seeds. The interaction with the hydrocolloids was analysed by thermogravimetry and derivative thermogravimetry, differential scanning calorimetry (DSC), viscoamylographic analysis (RVA) and X-ray powder diffraction (DRX). From the thermogravimetry, a similar behaviour was observed for all the studied samples, with three well-defined mass losses and a thermal stability plateau. The addition of guar gum promoted an increase in its thermal stability, unlike the sample added of CMC. From the DSC analysis, it was possible to observe a decrease in onset temperatures with the addition of hydrocolloids, which can be correlated with the decrease in pasting temperatures obtained by RVA, except for the carrageenan gum, which increased these temperatures. By RVA an increase in peak viscosities was achieved, highlighting the addition of CMC, pectin and xanthan. Small variations in the degree of relative crystallinity were noted, but no changes in the diffraction pattern occurred for the samples from the XRD analysis. Although native starch has some limitations, the synergistic effect produced by the addition of gums can optimise its technological properties expanding the industrial use.

Artificial Mucin-based Saliva Preparations - Physicochemical and Tribological Properties.

To create and investigate artificial mucin-based saliva substitutes with properties similar to natural saliva. Natural saliva and six saliva preparations were tested. Saliva substitutes were made using phosphate buffered saline (PBS) prepared in deionised water or plasma-treated water (PBSPT) with addition of porcine gastric mucin and guar gum or poloxamer 407. A wide range of properties were characterised: physicochemical (changes of pH, conductivity and surface tension over time: 1, 24, 96, 168 h after mixing ingredients), rheological (viscosity and viscoelasticity), tribological (coefficient of friction for titanium alloy Ti-6Al-7Nb kinematic couple) and corrosive (open circuit potential, corrosion potential, polarisation resistance). Saliva preparations based only on mucin had pH, viscosity, coefficient of friction and corrosion parameters similar to those of natural saliva. Guar gum increased the values of viscosity, viscoelasticity and the coefficient of friction. Similar results were obtained for poloxamer 407, whereas it decreased the surface tension of tested preparations. Plasma-treated PBS enhanced the corrosion resistance of saliva substitutes with guar gum and poloxamer 407. Among the tested compositions, saliva substitutes based only on mucin were found to have parameters similar to human whole saliva. Mucin saliva preparations may have wide applicability for patients with e.g. xerostomia or patients using a metal prosthesis.

Effect of hydrocolloids on the physico-chemical and rheological properties of reconstituted sweetened yoghurt powder.

The consistency of sweetened yoghurt (misti dahi) is a desired characteristic which is attributed to the casein protein network formation during fermentation. Unfortunately, this property is lost in reconstituted sweetened yoghurt (RSY) due to the irreversible nature of protein denaturation during spray drying. Therefore, this study aimed to increase the consistency of RSY using different hydrocolloids. The effects addition of guar gum, pectin, κ-carrageenan and gelatin (0.1%w/v each) on the physico-chemical, microbial, rheological and sensory properties of RSY were investigated. RSY with 40% total solids demonstrated the rheological properties which are very similar to those of fresh sweetened yoghurt. RSY containing different hydrocolloids further increased the rheological properties. The dynamic rheological study revealed that the magnitude of storage modulus (G'), loss modulus (G″), and loss tangent (tan δ) were significantly influenced by the addition of hydrocolloids and gelatin exhibited highest dynamic moduli in RSY. However, κ-carrageenan added RSY was preferred sensorially as the rheological properties were very close to gelatin added RSY. Addition of hydrocolloids significantly increased the starter bacteria count and pH and reduced water expulsion rate (P < 0.05). Addition of hydrocolloids can improve the rheological properties of reconstituted yoghurt. The study concluded that the addition of κ-carrageenan showed better results in terms of rheological and sensory properties of RSY. © 2017 Society of Chemical Industry.

Enhanced self-association and “weak gel” rheology of microdispersed oxidised cellulose (MDOC) by low concentrations of guar gum

The oxidised cellulose used was a proprietary product in which ∼75% of the glucose residues are converted to glucuronate and solubility is restricted by Ca2+ cations, giving small particles that are essentially insoluble in water. Aqueous dispersions of the resulting “microdispersed oxidised cellulose” (MDOC), although pourable, give gel-like mechanical spectra at concentrations above ∼4 wt %, far below the onset of close packing, due to adhesive interactions between the particles. Changes in the “weak gel” rheology of 5 wt % dispersions of MDOC in water on progressive addition of guar gum ([η] = 12.1 dL g-1; Mr ≈ 1.42 × 106) were characterised by low-amplitude oscillatory measurements of storage modulus (G′), loss modulus (G″) and complex dynamic viscosity (η*). Increasing concentration of guar gum caused an initial increase and subsequent decrease in G’. Maximum (∼5-fold) increase was observed at very low concentration of guar gum (∼0.04 wt %). The proposed interpretation is that guar gum promotes self-association of MDOC to minimise enthalpically-unfavourable (segregative) interactions in single-phase mixtures. The decrease in G′ at concentrations above the value required for maximum enhancement of network rheology is attributed to excessive aggregation of the gelling component.

Efficacy of fibre additions to flatbread flour mixes for reducing post-meal glucose and insulin responses in healthy Indian subjects.

The incidence of type 2 diabetes mellitus (T2DM) is increasing worldwide, including in developing countries, particularly in South Asia. Intakes of foods generating a high postprandial glucose (PPG) response have been positively associated with T2DM. As part of efforts to identify effective and feasible strategies to reduce the glycaemic impact of carbohydrate-rich staples, we previously found that addition of guar gum (GG) and chickpea flour (CPF) to wheat flour could significantly reduce the PPG response to flatbread products. On the basis of the results of an exploratory study with Caucasian subjects, we have now tested the effect of additions of specific combinations of CPF with low doses of GG to a flatbread flour mix for their impacts on PPG and postprandial insulin (PPI) responses in a South-Asian population. In a randomised, placebo-controlled full-cross-over design, fifty-six healthy Indian adults consumed flatbreads made with a commercial flatbread mix (100 % wheat flour) with no further additions (control) or incorporating 15 % CPF in combination with 2, 3 or 4 % GG. The flatbreads with CPF and 3 or 4 % GG significantly reduced PPG (both ≥15 % reduction in positive incremental AUC, P<0·01) and PPI (both ≥28 % reduction in total AUC, P<0·0001) compared with flatbreads made from control flour. These results confirm the efficacy and feasibility of the addition of CPF with GG to flatbread flour mixes to achieve significant reductions in both PPG and PPI in Indian subjects.

Guar gum as biosourced building block to generate highly conductive and elastic ionogels with poly(ionic liquid) and ionic liquid

In this study, we report on the simple and straightforward preparation of ionogels arising from the addition of guar gum (a plant-based polysaccharide) in a solution of precisely-defined poly(ionic liquid) chains (PIL) in imidazolium-based ionic liquid (IL). The development of intermolecular polar interactions (mainly hydrogen bonds) and topologic chain entanglements induces the formation of physical biohybrid ionogels, whose elastic properties can be easily tuned by varying the composition (up to 30000Pa). The combined presence of guar gum and PIL confers excellent dimensional stability to the ionogels with no IL exudation combined with high thermal properties (up to 310°C). The resulting materials are shown to exhibit gel scattering profiles and high conductivities (> 10−4S/cm at 30°C). The benefit linked to the formation of guar/PIL associations in IL medium enables to find a good compromise between the mechanical cohesion and the mobility ensuring the ionic transport.

Acute effects of different dietary polysaccharides added in milk on food intake, postprandial appetite and glycemic responses in healthy young females

In the present study we compared the postprandial glycemic and satiety responses of different dietary polysaccharides when added in milk (2% M.F.). The objective of this study was to evaluate different polysaccharides against postprandial glucose, appetite responses and food intake at subsequent meal. In a repeated measures design, 30 females (18–30 years) consumed 250 ml milk 2% M.F. (control), or milk with carrageenan (2.5 g), guar gum (2.5 g) and alginate (2.5 g), followed by an ad libitum pizza meal after 120 min. Alginate and guar gum addition resulted in lower caloric intake at subsequent pizza meal. The post-treatment (0–120 min) glucose and average appetite were suppressed by alginate and guar gum (p < 0.0001), with more pronounced effect of guar gum. However, alginate resulted in lower blood glucose (p < 0.0001) compared with control and carrageenan during post-treatment. Alginate and guar gum added beverages would be beneficial in short-term regulation of postprandial glycemia and satiety.

Effect of stabilizers, oil level and structure on the growth of Zygosaccharomyces bailii and on physical stability of model systems simulating acid sauces

The effect of xanthan gum, guar gum, oil and the structure promoted by these compounds on the growth of Zygosaccharomyces bailii and on physical stability of emulsified systems simulating acid sauces was studied. Furthermore, the effect of yeast growth on physical stability of emulsions was also evaluated.Yeast growth was evaluated by plate count and modeled by the modified Gompertz equation. Emulsions characteristics and their stability were determined by droplet size, zeta potential and rheological measurements. The latter was also used to evaluate structure's effect on yeast growth.Physical characteristics of emulsions depended on system composition. Yeasts slightly affected droplet size. Z. bailii growth was satisfactorily modeled by the modified Gompertz equation. The specific growth rate (μm) and the asymptotic value (A) obtained depended on xanthan gum, guar gum and oil content. Furthermore, the structure promoted by these compounds exerted a significant effect on growth. In general, an increase in the solid character and yield stress through the addition of xanthan gum promoted a decrease in A parameter. On the contrary, a decrease in the solid character through the addition of guar gum promoted an increase in the A parameter. The results obtained stressed that stabilizers, oil and their structuring ability play an important role on Z. bailii growth.

Biodegradation of crosslinked polyurethane acrylates/guar gum composites under natural soil burial conditions

Abstract This study investigated the effect of the guar gum content on the degradation behavior of the polyester and polyether polyurethane acrylate composites under outdoor soil-burial exposure. Polyurethane acrylates-guar gum composites were characterized before and after soil degradation by Fourier transform infrared spectroscopy (FTIR), mechanical measurements and scanning electron microscopy (SEM). The results showed that the addition of guar gum produces significant improvement in the degradation rate of these composites. The guar gum filler’s susceptibility to humidity and to soil microorganisms resulted in significant chemical and morphological changes in the entire structure of the composite. Guar gum incorporation into the matrix of the crosslinked polyurethane acrylates leads to a significant decrease in the mechanical properties of the composite films after soil burial exposure.

Effect of Different Combinations of Gums and Emulsifiers on the Quality of Bread

A project was designed to evaluate the effect of different combinations of emulsifiers and gumson the quality of bread. Wheat variety AARI-11 was milled to get straight grade flour and mixed with theEmulsifiers (DMG &amp; DATEM) and Gums (G.G &amp; CMC) in a quantity of (0.3- 0.6 %). Both, straight gradeflour as well as treated flour (combination with gums and emulsifiers) were subjected to proximate andrheological analysis. Results of the rheological study showed a significant change in water absorption,dough development time, dough stability time and dough viscosity i.e. W/A 61.33-62.93%, D.D.T 3.9-4.8 min, D.S.T 7-9.1 min and 818.33-950.00 BU, respectively. Breads prepared with both flours were alsostudied for their sensory attributes during storage after the interval of 24 h. The highest score was awardedto T1 (0.3% DATEM &amp; 0.5% guar gum) on the bases of its excellent external attributes (colour of crust,volume, symmetry of form, evenness of bake and crust character) and internal characteristics (aroma, grain,texture, taste, mastication and colour of crumb). After the sensory and physicochemical analyses, it isconcluded that with the addition of DATEM (0.3%) and guar gum (0.5%) resulted in good quality of bread.

Preparation and characterization of cellulose composite hydrogels from tea residue and carbohydrate additives

Composite hydrogels were prepared from tea cellulose in ionic liquid of 1-allyl-3-methylimidazolium chloride and effect of κ-carrageenan, chitosan, guar gum and soluble starch on characteristics of the prepared hydrogels were investigated. The prepared hydrogels were characterized via Fourier transform infrared, thermogravimetry analysis, differential scanning calorimetry. Sodium salicylate was used as the model drug to compare the swelling, drug loading and releasing kinetics of the prepared hydrogels. Thiazolyl blue tetrazolium bromide assay and relative growth rates were adopted to evaluate cell cytotoxicity and biocompatibility of the prepared hydrogels. Chitosan and guar gum could improve thermostability and mechanical characteristics of the composite hydrogels, while κ-carrageenan or soluble starch could improve equilibrium swelling ratio, sodium salicylate loading and releasing. Guar gum and chitosan could increase permeation resistance and were beneficial for release control of the hydrogels. Addition of chitosan, κ-carrageenan, guar gum and soluble starch were proven cell compatibility and non-cytotoxicity.

Influence of guar gum addition on physicochemical, microbial, rheological and sensory properties of stirred yoghurt

This study investigated the effects of adding guar gum (0, 0.6 and 0.8 g/100 mL) on the physicochemical, microbial, rheological and sensory properties of stirred yoghurt. Incorporation of guar gum into the yoghurt significantly affected the pH and colour, but did not significantly influence the lactic acid bacteria counts. The magnitudes of apparent viscosity (ηa,100), consistency index (K), yield stress (σoc), storage modulus (G′) and loss modulus (G″) for yoghurt samples containing guar gum (0.6–0.8 g/100 mL) were significantly greater than those for the control (without guar gum), indicating that guar gum can improve the steady and dynamic shear rheological properties of yoghurt.

Influence of additives on dough rheology and quality of Thepla: an Indian unleavened flatbread

Thepla is Indian unleavened flatbread made from whole-wheat flour with added spices and vegetables. In the present study, effect of addition of various emulsifiers such as sodium stearoyl-2-lactylate (SSL), di acetyl tartaric acid ester of monoglyceride (DATEM) and glycerol mono-stearate (GMS) were studied. Further hydrocolloids (guar gum, carrageenan) and modified polysaccharides [hydroxypropyl methylcellulose (HPMC) and carboxymethyl cellulose] were added at the concentration ranging from 0.25 to 1 % on the basis of whole wheat flour to prepared the doughs. These thepla doughs were analyzed for rheology and theplas were analyzed for tear force. Additives helped in improvement of dough and thepla quality. Guar gum increased dough stickiness and strength to the highest (31.12 and 1.76 g respectively). Also, guar gum decreased tear force value of thepla to 208.4 g. Tear force was found to be increasing with the duration of storage. Highest improvement in thepla dough and quality was obtained by the addition of guar gum at 0.75 % which retained the softest texture of thepla.

Effect of the addition of hydrocolloids on the rheological and baking properties of the products with added spelt flour (Triticum spelta L.)

The paper presents the results of the evaluation of the effect of additives on the rheological properties of composite flour made of wheat flour in the amount of 70% and spelt flour at 30%. As additives guar gum (0.5% by weight of flour) and xanthan gum (0.16% by weight of flour) were used. Properties of produced control dough and doughs with hydrocolloids were evaluated by means of rheological appliances by Farinograph, Extenzograph, Amylograph and Rheofermentometer. Based on the observed results it can be concluded that the addition of xanthan gum has a positive effect on increasing of farinographic water absorption capacity, extension of dough development time and dough stability and generally positively affected farinographic properties. The addition of guar gum has improved especially extensographic properties as extensographic energy and extensographic resistance. Based on amylographic evaluation of control doughs and doughs with additives it can be stated that in the dough with guar gum the amylographic maximum has slightly increased. Hydrocolloid guar gum contributed to an increased retention capacity of dough observed. Based on our measurements we can indicate that addition of guar and xanthan gum contributed to an increased rheological quality of doughs prepared with addition of flour from spelt wheat. With reference to the baking experiment it was found that the use of hydrocolloids has a positive effect on the improvement of the baking properties, in particular larger volume, specific volume, and the volume yield of the dough with the addition of guar and xanthan gum compared to the control. Our results showed that aditives significantly influenced rheological qualities of dough and a baking quality of products. These findings thus allow optimizing the recipe in order to increase the technological quality of leavened bakery products.

Digestion of starch in a dynamic small intestinal model.

The rate and extent of starch digestion have been linked with important health aspects, such as control of obesity and type-2 diabetes. In vitro techniques are often used to study digestion and simulated nutrient absorption; however, the effect of gut motility is often disregarded. The present work aims at studying fundamentals of starch digestion, e.g. the effect of viscosity on digestibility, taking into account both biochemical and engineering (gut motility) parameters. New small intestinal model (SIM) that realistically mimics gut motility (segmentation) was used to study digestibility and simulated oligosaccharide bio accessibility of (a) model starch solutions; (b) bread formulations. First, the model was compared with the rigorously mixed stirred tank reactor (STR). Then the effects of enzyme concentration/flow rate, starch concentration, and digesta viscosity (addition of guar gum) were evaluated. Compared to the STR, the SIM showed presence of lag phase when no digestive processes could be detected. The effects of enzyme concentration and flow rate appeared to be marginal in the region of mass transfer limited reactions. Addition of guar gum reduced simulated glucose absorption by up to 45% in model starch solutions and by 35% in bread formulations, indicating the importance of chyme rheology on nutrient bioaccessibility. Overall, the work highlights the significance of gut motility in digestive processes and offers a powerful tool in nutritional studies that, additionally to biochemical, considers engineering aspects of digestion. The potential to modulate food digestibility and nutrient bioaccessibility by altering food formulation is indicated.

Rheological Behavior of Artificial Flocculated Clay/Guar-Gum Suspensions

In this paper, artificial flocs, similar to the ones that are found in a recently deposited cohesive seabed, were prepared using Ca-montmorillonite and kaolinite (two of the most abundant clay minerals), guar gum (a polysaccharide closely resembling natural marine organic matter), and artificial sea water, in order to investigate the effect of the composition on their rheological response. Shear rate effects on viscosity of these suspensions were also systematically addressed. These effects typically have a strong influence on the overall rheological response of materials incorporating any polymeric substance. It was found that the addition of guar gum, even as little as 5% relative to the clay content, increases the viscosity of the floc suspensions significantly. The higher the guar-gum and clay content, the greater is the viscosity of the floc suspensions, within the guar-gum loading range investigated in this study. The floc suspensions with higher solid content were found to exhibit a slight shear thinning behavior, apparently due to the breakdown of the floc structure under high shear stress. This behavior is more pronounced in montmorillonite floc suspensions than in the kaolinite suspensions due to the differences in the clay mineral surface charge properties and surface-to-mass ratios. We explore different rheological models in their applicability to describing the observed viscous response and conclude that a cross-type formulation may be most appropriate.

Soluble Dietary Fibers Can Protect the Small Intestinal Mucosa Without Affecting the Anti-inflammatory Effect of Indomethacin in Adjuvant-Induced Arthritis Rats.

How to prevent the small intestinal damage induced by NSAIDs is an urgent issue to be resolved. In the present study, we examined the effects of soluble dietary fibers on both anti-inflammatory and ulcerogenic effects of indomethacin in arthritic rats. Male Wistar rats weighing 180-220 g were used. Arthritis was induced by injecting Freund's complete adjuvant (killed M. tuberculosis) into the plantar region of the right hindpaw. The animals were fed a regular powder diet for rats or a diet supplemented with soluble dietary fibers such as pectin or guar gum. Indomethacin was administered once a day for 3 days starting 14 days after the adjuvant injection, when marked arthritis was observed. The volumes of the hindpaw were measured before and after indomethacin treatment to evaluate the effect of indomethacin on edema. The lesions in the small intestine were examined 24 h after the final dosing of indomethacin. Hindpaw volume was increased about 3 times 14 days after injection of the adjuvant. Indomethacin (3-10 mg/kg, p.o.) decreased hindpaw volume dose-dependently, but caused severe lesions in the small intestine at doses of 6 and 10 mg/kg. The addition of pectin (1-10 %) or guar gum (10 %) to the diet markedly decreased the lesion formation without affecting the anti-edema action of indomethacin. The same effects of pectin were observed when indomethacin was administered subcutaneously. It is suggested that soluble dietary fibers can prevent intestinal damage induced by NSAIDs without affecting the anti-inflammatory effect of these agents.

Guar Gum이 순두부찌개 소스의 품질 특성에 미치는 영향

The aim of this study was to investigate the effects of guar gum on the rheological behaviors, sensory attributes, and consumer acceptability of soft tofu stew sauce. Five different soft tofu stew sauces were commercially manufactured with various levels of guar gum (0.0, 0.1, 0.2, 0.4, and 0.5%). Twelve sensory attributes of the stew sauces were identified by nine trained descriptive panelists, whereas hedonic levels of the stew sauces were assessed by a group of 51 consumers. Steady flow of the stew sauces were measured by a rheometer. Significant differences were observed in terms of sensory saltiness and viscosity among the products. For the consumer test, 0.1% guar gum-added product was most liked by consumers. Partial least square regression showed sensory shellfish, green onion, and shrimp flavors to be key factors affecting overall acceptability for the stew sauces. For rheological behaviors, 0.0, 0.1, and 0.2% guar gum-added products showed newtonian behaviors (R 2 =0.99 by power law model), whereas 0.4 and 0.5% products followed pseudoplastic behaviors (R 2 =0.99 by power law model). Based on the established equivalence table using rheological and consumer data, smaller than 0.0114 (Pa·s) of the apparent viscosity should be necessary to guarantee ‘slightly like’ category in a consumer hedonic test. It seems that addition of guar gum not only influenced rheological properties but overall acceptability for the stew sauces.

Effects of hydrocolloids on corn starch retrogradation

In this work, three kinds of hydrocolloids were used to investigate the effect of short‐term and long‐term retrogradation of corn starch to understand the mechanism of the hydrocolloid action on starch granules. Various analytical techniques, including the rapid viscosity analyzer, rheometer, differential scanning calorimetry (DSC), and dispersion stability analyzer, were used to determine the gelatinization and phase separation behavior and to understand the effect of hydrocolloids on the mechanism of starch retrogradation. DSC revealed that short‐term retrogradation of amylose was retarded and restricted by xanthan gum. The X‐ray diffraction indicated that the xanthan gum could prevent the recrystallization of amylopectin. The stability analysis, which was performed with the Turbiscan Easy Soft software, clearly suggested that addition of xanthan and guar gum can strongly stabilize the corn starch; this was quantified using the Turbiscan stability index. Thus, our results showed that xanthan and guar gum can improve the stability of corn starch/hydrocolloid systems.

Formulation of mayonnaise with the addition of a bioemulsifier isolated from Candida utilis.

Biosurfactants have a number of industrial applications due their diverse properties, such as emulsification, foaming, wetting, and surface activity. The aim of the present study was to produce a biosurfactant from Candida utilis and employ it in the formulation of a mayonnaise. The biosurfactant was produced in a mineral medium supplemented with glucose and canola waste frying oil at 150rpm for 88h. The product was biologically tested on rats and in different formulations of mayonnaise, which were submitted to microbiological evaluations. The biosurfactant was added to the diet of the rats for 21 days. Greater consumption was found of the experimental diet. Moreover, no changes were found in the liver or kidneys of the animals, demonstrating the absence of a toxic effect from the biosurfactant. Six different formulations of mayonnaise were prepared and tested regarding stability with the addition of carboxymethyl cellulose and guar gum (combined and isolated) after 30 days of refrigeration. The most stable formulation with the best quality was obtained with combination of guar gum and the isolated biosurfactant, with an absence of pathogenic microorganisms. In conclusion, the potential and innocuousness of the biosurfactant isolated from C. utilis indicates its safe use in food emulsions.