Dielectric and Thermal Properties of Rice Cake Formulations Containing Different Gums Types

In this study, dielectric properties of rice cake formulations containing different gum types (xanthan, guar, locust bean, HPMC, and kappa-carrageenan) were determined at temperatures between 25 and 90°C at 2450 MHz. Moreover, thermal properties of these formulations were determined by using differential scanning calorimeter (DSC). Dielectric properties of cake batters were found to be dependent on cake formulation. Xanthan and guar gum containing cake batters had the highest dielectric constant and loss factor values at 25°C. Temperature dependence of dielectric properties was not significant until temperature of 85°C. Gelatinization enthalpy of batter increased with the addition of gums.     

Thermal,microscopic, and quality properties of low-fat frankfurters and emulsions produced by addition of different hydrocolloids

This study involves investigation of the effects of addition of different hydrocolloids on the thermal, microscopic, and quality properties of low-fat meat emulsions and frankfurters. The emulsion stability of the samples containing 0.5% κ-carrageenan, λ-carrageenan or chitosan, and the 1% chitosan containing sample were lower than that of the control group. Thermal analyses showed three denaturation peaks for minced meat at 57.42 °C, 64.21 °C and 78.58 °C. While the denaturation temperature of myosin for the sample produced with 0.5% of κ-carrageenan was significantly lower, samples containing 1% κ-carrageenan and 0.5% λ-carrageenan were not significantly different than that of the control group. The thermal denaturation temperature of myosin for samples containing 1% λ-carrageenan, and for 0.5% and 1% guar gum, xanthan gum and chitosan was significantly higher than that of the control. The denaturation temperature of sarcoplasmic proteins and actin for samples with 1% κ- and λ-carrageenan and 0.5% chitosan, was higher than for the control, while for other samples it was not significantly different. The scanning electron microscopy images of the control group and samples produced with 0.5% and 1% λ-carrageenan, 0.5% and 1% guar gum, and 1% κ-carrageenan showed gel-like structures, whereas other samples did not. Sensory evaluations showed that addition of hydrocolloids and reduced fat content lowered acceptance of frankfurters. Results showed that both κ- and λ-carrageenan, especially at 0.5% were the most suitable hydrocolloids for production of low-fat frankfurters and xanthan gum was the least suitable since it did not form proper structure.     

Effect of locust bean/xanthan gum addition and replacement of pork fat with olive oil on the quality characteristics of low-fat frankfurters

The effects of reducing fat level from 20% to 12% and 9%, substituting pork fat with olive oil and adding locust bean/xanthan gum (0.5% and 0.6%) on emulsion stability, jelly and fat separation, processing yield, cook loss, texture and sensory characteristics of frankfurters were investigated and compared with control samples. Addition of locust bean/xanthan gum produced a significant increase in hydration/binding properties, characterised by lower cook losses, increasing yield, better emulsion stability and lower jelly and fat separation. The substitution of pork fat by olive oil did not affect these parameters. Indeed, results showed that reducing fat levels together with increasing moisture and locust bean/xanthan gum addition do not affect the sensory or textural properties, but olive oil addition produces a decrease in hardness and an increase in adhesiveness, however the overall acceptability was not affected.     

黄原胶与几种胶复配对花生乳稳定性的影响

研究了黄原胶分别与刺槐豆胶、瓜尔豆胶、魔芋胶复配对花生乳稳定性的影响,通过分析样品沉淀率、油脂析出率、粘度及高温稳定性观察,结果表明,黄原胶与瓜尔豆胶复配时花生乳稳定性最好,最佳复配比例为黄原胶:瓜尔豆胶=1:2,最佳复配用量为0.05 %.     

Effects of nonprotein substances on protein hydrolysis and plastein formation

Effects of various naturally occurring nonprotein substances (carbohydrates, polysaccharides, fats and salts) on enzymatic hydrolysis of soy protein isolate and plastein formation from hydrolyzed soy protein were investigated. Relative extent of hydrolysis and plastein formation were measured as protein solubility in 10% trichloroacetic acid (TCA) since this method was found suitable for analysis of turbid, viscous and/or low protein samples. The presence of guar, xanthan, locust bean and arabic gums, arabinogalactan, unsaturated fatty acids (2%), salt mixture and xylan were found to enhance soy protein peptic hydrolysis at 0·5% enzyme/substrate; unsaturated fatty acids (1%) inhibited hydrolysis. At enzyme/substrate of 3·5%, hydrolysis was enhanced by xanthan gum, unsaturated fatty acids and sodium chloride but inhibited by gum karaya, salt mixture, starch, cellulose, and saturated fatty acids. Plastein synthesis was inhibited by xanthan, locust bean and guar gums but stimulated by arabinogalactan. Several nonprotein substances were found to interfere with the TCA solubility assay. Positive interference was noted for systems containing saturated and unsaturated fatty acids and magnesium, but negative interference was observed for systems containing guar gum, xanthan gum, calcium chloride and gum arabic.     

Rheological behaviour of pullulanase-treated guar galactomannan on co-gelation with xanthan

The present study involves the use of non-specific enzyme pullulanase (from Bacillus acidopullulyticus) to remove galactose residues from guar galactomannan to obtain modified guar galactomannan mimicking the functional properties of locust bean gum. The modified guar galactomannan blended with xanthan exhibited the rheological behaviour of elastic modulus (G′) greater than viscous modulus (G″) with a decrease in tan δ value similar to locust bean gum/xanthan blend. Also a twofold increase in the magnitude of elasticity compared to xanthan alone suggested the synergistic interaction with formation of three dimensional networks. The modified guar galactomannan with galactose content of 21% and M:G ratio 1:3.8, almost akin to locust bean gum, showed a better interaction with xanthan. Dynamic stress sweep study of modified guar galactomannan/xanthan blend with increased yield stress of 800 dynes/cm² also indicated the synergistic behaviour. Modified guar galactomannan also revealed the maximum synergistic interaction with xanthan at a mixing temperature of 60 °C than at 20 °C, 30 °C, 40 °C and 50 °C, respectively. Modification of guar galactomannan by pullulanase is an alternative route to produce galactose-depleted guar galactomannan with enhanced rheological functionalities on co-gelation with xanthan, as a cost effective replacement to locust bean gum.     

SIMULATING VISCOELASTIC PROPERTIES OF SELECTED FOOD GUMS AND GUM MIXTURES USING A FRACTIONAL DERIVATIVE MODEL

A four parameter semi-empirical model has been developed using the fractional derivative (FD) theory, which consists of applying a mathematical operator to a constitutive equation. The Fourier transform approach is used to obtain the analytical function of the derived model. Since a single four parameter model can predict both storage modulus (G') and dynamic viscosity (η'), the developed FD model was appropriate in describing the viscoelastic properties of selected food gum dispersions, food gum mixtures and gellan gel. This fractional derivative model shows good simulation capability for selected food gum dispersions (0.5% xanthan gum, 0.5 and 0.75% locust bean gum, and 0.5, 0.75, and 1.0% guar gum), 0.6% gellan gel, and binary mixtures of carrageenan and guar gum, car-rageenan and xanthan, as well as guar and xanthan gum.     

Effects of batters containing different gum types on the quality of deep‐fat fried chicken nuggets

The effects of various gum types [hydroxypropylmethylcellulose (HPMC), guar gum, xanthan gum, gum arabic] on the quality of deep‐fat fried chicken nuggets were studied. Chicken samples, 0.04 m in diameter and 0.015 m in thickness taken from the breast portion, were coated with batters composed of a 3:5 solid to water ratio by immersion. The solid content of batter formulations contained equal amounts of corn and wheat flours, 1.0% gum, 1.0% salt and 0.5% leavening agent. As control, batter without gum addition was used. Samples were fried at 180 °C for 3, 6, 9 and 12 min. The hardness and oil content of the chicken nuggets increased whereas the moisture content decreased during frying. HPMC and xanthan gums reduced oil absorption significantly compared with other gums and the control. When gum arabic was added to the batter formulation, a product with the highest oil content and porosity was obtained. Copyright © 2005 Society of Chemical Industry     

Viscosity of solutions of xanthan/locust bean gum mixtures

Xanthan and locust bean gums are polysaccharides able to produce aqueous solutions with high viscosity and non‐Newtonian behaviour. When these solutions are mixed a dramatic increase on viscosity is observed, much greater than the combined viscosity of the separated polysaccharide solutions. In this work the influences of different variables on the viscosity of solutions of mixtures of xanthan/locust bean gum have been studied. Total polysaccharide concentration, xanthan and locust bean ratio on mixture and temperature at which the gum was dissolved (dissolution temperature) for both xanthan and locust bean gums have been considered. Under these different operational mixture conditions shear rate and time have also been considered to describe the rheological behaviour of the solutions studied. The high viscosity increase observed in these mixtures is due to the interaction between xanthan gum and locust bean gum molecules. This interaction takes place between the side chains of xanthan and the backbone of the locust bean gum. Both xanthan molecule conformation in solution – tertiary structure – and locust bean gum structure show great influence on the final viscosity of the solution mixtures. Xanthan conformation changes with temperature, going from ordered structures to disordered or chaotic ones. Locust bean gum composition changes with dissolution temperature, showing a dissolved galactose/mannose ratio reduction when temperature increases, ie the smooth regions – zones without galactose radicals – are predominantly dissolved. The highest viscosity was obtained for the solution mixture with a total polysaccharide concentration of 1.5 kg m⁻³ and a xanthan/locust ratio of 2:4 (w/w) and when xanthan gum and locust bean gum were dissolved at 40°C and 80°C, respectively. © 1999 Society of Chemical Industry     

Optimization of Gum Combination in Prebiotic Instant Hot Chocolate Beverage Model System in Terms of Rheological Aspect: Mixture Design Approach

Mixture design was used to investigate the effects of four different gums (xanthan gum, guar gum, alginate and locust bean gum) and their combinations on the rheological properties of a prebiotic model instant hot chocolate beverage (including 3.5% inulin) and to determine their interactions in the model beverage. Simplex centroid mixture design was applied to predict the physicochemical (soluble solids, pH, colour properties) and rheological parameters (consistency index (K), flow behaviour index (n) and apparent viscosity (η ₅₀)) of the samples. In the model, the optimum gum combination was found by simplex centroid mixture design as 59% xanthan gum and 41% locust bean gum, and the highest K value was 33.56 Pa s ⁿ . The increase of guar gum and alginate in the gum mixture caused a decrease in the K value of the sample.     

Interactions of κ-carrageenan Plus Other Hydrocolloids in Fish Myosystem Gels

ABSTRACT: Mixtures of κ-carrageenan plus other hydrocolloids (locust bean, guar, xanthan, iota-carrageenan, sodium carboxymethylcellulose, and sodium alginate) were examined for their effects on the mechanical and water holding properties of heat-induced gels made from washed blue whiting mince. Gel structure and thermal behavior were also studied. No synergistic effect was detectable through functional properties except for the mixture of κ-carrageenan with locust bean gum. Light microscopy revealed that κ-carrageenan and xanthan mixed locally with locust bean at its rich domains. κ-carrageenan and xanthan presented interactions with the protein matrix, which were more discernible in the first case. Differential scanning calorimetry (DSC) revealed faint interactions for the mixtures of κ-carrageenan with locust bean and with xanthan, and weakly synergistic gelling effects between the last two hydrocolloids. The blend of κ-carrageenan with sodium alginate exhibited thermally strong synergistic interactions but no particular effects were induced on corresponding functional properties.     

Controlling rheology and structure of sweet potato starch noodles with high broccoli powder content by hydrocolloids

Incorporating high volume fractions of broccoli powder in starch noodle dough has a major effect on its shear modulus, as a result of significant swelling of the broccoli particles. Several hydrocolloids with distinct water binding capacity (locust bean gum (LBG), guar gum, konjac glucomannan (KG), hydroxypropyl methylcellulose (HPMC) and xanthan gum), were added to systems with 4 and 20% (v/v dry based) broccoli particles, and the effect of this addition on dough rheology, mechanical properties and structure of cooked noodles was investigated. Hydrocolloids with low (LBG and guar gum) and intermediate (KG) water binding capacity had no significant effect on shear rheology of the dough. Adding hydrocolloids with high water binding capacity (HPMC and xanthan gum) decreased the shear modulus of dough with 20% broccoli particles significantly. CLSM analysis of cooked noodles showed that in samples containing xanthan gum there was also an inhibition of swelling of starch granules. Strength and stiffness of cooked noodles with 20% broccoli particles were higher for samples containing xanthan gum, than samples without xanthan gum. The cooking loss and swelling index of samples with added hydrocolloids were slightly lower than samples without hydrocolloids. Our results showed that hydrocolloids with high water binding capacity can be used to control the degree of swelling of vegetable particles and starch granules in starch noodle products, and thereby control both dough rheology and textural properties of the cooked noodles.     

Rheological interactions between Lallemantia royleana seed extract and selected food hydrocolloids

BACKGROUND: Lallemantia royleana (Balangu) is a mucilaginous endemic plant which is grown in different regions of world. The flow behaviour of Balangu seed extract (BSE) and its mixture with xanthan, guar and locust bean gums at 1:3, 1:1 and 3:1 ratios, in addition to control samples (0% BSE), were evaluated. To describe the rheological properties of samples, the power law model was fitted on apparent viscosity–shear rate data. To evaluate the interaction between BSE and selected hydrocolloids in dilute solutions, the relative viscosity was also investigated. RESULTS: There was no significant difference between the consistency coefficient of guar and locust bean solutions and their blends substituted with 250 g kg^?1 BSE. The BSE–xanthan mixture at 1:3 and 1:1 ratios had consistency index equal to xanthan solution. BSE–locust bean gum at all ratios, BSE–xanthan at 1:3 ratio and BSE–guar gum at 1:1 and 3:1 ratios indicated relative viscosity lower than values calculated assuming no interaction. The intrinsic viscosity value of BSE was determined 3.50 dL g^?1. CONCLUSION: The apparent viscosities of BSE, selected hydrocolloids and their blends were the same at a shear rate of 293 s^?1 and the commercial gums can be substituted by 250 g kg^?1 and 500 g kg^?1 BSE. Copyright © 2011 Society of Chemical Industry     

Comparison of the effects of gums on dynamic rheological properties of acetylated sweet potato starch

Dynamic rheological properties of acetylated sweet potato starch (ASPS) pastes mixed with 3 commercial gums (guar gum, locust bean gum, and xanthan gum) were investigated at different gum concentrations. The dynamic moduli of the ASPS-gum mixtures were higher than those of the control, and they increased with an increase in gum concentration. In particular, the G′ value of xanthan and G″ value of guar gum at a 0.6% gum concentration were much higher as compared to those of other mixtures. Tan δ values of ASPS-xanthan mixtures were much lower than those of other samples, indicating that the elastic properties in the ASPS-gum mixture systems were strongly affected by the additions of xanthan. These results suggest that the presence of gums in ASPS modifies the viscoelastic properties, and that these modifications are dependent on the gum type and gum concentration.     

Rheological properties of batter systems containing different combinations of flours and hydrocolloids

The rheological properties of batters formulated using different combinations of wheat, corn, and rice flours with two types of hydrocolloids, namely methylcellulose (0.5%, 1% and 1.5%) or xanthan gum (0.2%), were studied. Control samples were formulated with combinations of flours without the added hydrocolloids. The effects of hydrocolloids on rheological characteristics of the batter systems were measured using a controlled stress rheometer at a temperature of 15 °C. The effects of hydrocolloids on dynamic viscoelastic parameters as functions of temperatures were evaluated. All the batters showed shear thinning behaviour with flow behaviour indices in the range 0.34–0.67. Addition of xanthan gum lowered the flow index values, imparting a higher degree of pseudoplasticity to the batter samples compared to methylcellulose. The consistency index of the control batter samples varied from 0.46 to 69.2 Pa sⁿ. Addition of xanthan gum or methylcellulose significantly increased the batter consistency index value. The gums changed the onset temperature of structure development, and the storage (G′_max) and loss moduli (G″_max) of the batter systems. However, no statistically significant effects were observed on the peak temperature of batter systems in which the G′ reached a maximum value. Xanthan gum increased both G′_max and G″_max, whereas at higher concentrations methylcellulose increased G′_max but lowered G″_max. Copyright © 2007 Society of Chemical Industry     

Effect of Anionic Gums on the Texture of Pickled Frankfurters

The addition of the anionic gums, xanthan and carrageenan, stabilized the texture of frankfurter emulsions against acid deterioration at 37°C in vinegar pickle. The proteins collagen, casein, and gluten, and the gums guar, arabic, and locust bean had no effect. The cationic gum, chitosan, formed an acid-stable gel but the gel would not hold the emulsion. The process of acid deterioration had an initial period of firming of the gel texture. Shear (rupture) and elasticity did not show a corresponding initial increase. Subsequent deteriorative changes were less in the emulsions with xanthan gum than in any of the other emulsions. The gum gel is formed at the expense of the protein-fat structure, probably through a gum-protein interaction.     

黄原胶的流变性及与魔芋胶等的协效性研究

研究前期筛选获得一株多糖胶质高产菌Xanthomonas axonopodis所产的黄原胶FJAT-10151-DTJZ的品质,为该黄原胶的开发应用提供基础数据及参考。通过分析浓度、剪切速率、p H、加热温度、时间、冻融处理等对FJAT-10151-DTJZ粘度的影响研究其流变性,并研究其与结冷胶、黄原胶、凝胶多糖、瓜尔豆胶、刺槐豆胶、魔芋胶、果胶和壳聚糖8种胶的协效性。实验结果表明,FJAT-10151-DTJZ溶液的粘度随浓度的升高而升高,且为非牛顿流体;当FJAT-10151-DTJZ的浓度为1%时,其粘度为343 m Pa·s;p H、冻融对FJAT-10151-DTJZ的粘度影响不大;FJAT-10151-DTJZ的最佳加热温度为75℃;粘度随加热时间先增大后减小,当加热温度为75℃,加热时间为150 min,1%浓度的FJAT-10151-DTJZ溶液的粘度为808 m Pa·s。FJAT-10151-DTJZ只与魔芋胶有强烈的协同增效作用,与壳聚糖、结冷胶、黄原胶、凝胶多糖、瓜尔豆胶、刺槐豆胶、果胶无协效性。      

TEXTURE STABILITY OF HYDROGEL COMPLEX CONTAINING CURDLAN GUM OVER MULTIPLE FREEZE–THAW CYCLES

The texture stability of hydrogel complexes containing curdlan gum over multiple freeze–thaw cycles (FTCs) was investigated. The hydrogels formed by curdlan and xanthan gum, locust bean gum, carrageenan or guar gum at various combinations were stored at 4C for 24 h before subjected to five FTCs alternating between − 16 (18 h) and 25C (6 h). Xanthan/curdlan hydrogels showed the highest freeze–thaw stability in terms of syneresis, heat stability and adhesiveness. The viscosity of xanthan/curdlan combination was the lowest among all samples studied yet the most stable over the five FTCs, whereas significant changes were observed with locust bean/curdlan hydrogels. The guar/curdlan combination before freeze–thaw treatments exhibited predominant elasticity; however, as the cycles progressed the elasticity decreased. The most stable gel strength was achieved when curdlan was combined with guar or xanthan at 2% (w/v) total concentration, while carrageenan/curdlan gels were the least stable.

PRACTICAL APPLICATIONS

Texture instability remains the most significant challenge for frozen food products, especially with inevitable post-production temperature fluctuations. Loss of moisture and changes in textural attributes often results in significant reduction of product quality. Precise control of hydrogel complexes that provide texture stabilization over multiple freeze–thaw cycles will enhance the quality of existing products while enabling the development of new ones.     

Hydrocolloids in emulsions: particle size distribution and interfacial activity

The emulsification properties of 14 hydrocolloid gums (propylene glycol alginate, gellan, carrageenan, pectin, methylcellulose, microcrystalline cellulose, gum arabic, locust bean gum, guar, xanthan, mustard, flaxseed, fenugreek, oat) were investigated. Gum dispersions were prepared in water (0.5%) and emulsified with 40% oil using a Polytron homogenizer. Emulsion stability was determined by centrifugation and storage time, surface and interfacial tension by Du Nouy ring, particle size by integrated light scattering and overall morphology by light microscopy. When compared to the other gums in this study, fenugreek produced a very stable emulsion. Fenugreek was more efficient than other gums in lowering the interfacial free energy, its emulsion was composed of very small oil droplets (70%<1 μm) and under the light microscope appeared as uniform droplets with a narrow size distribution.     

Effects of food gums and pre-drying on fat content of fabricated fried chips

Deep-frying contributes to the unique taste and texture of fried products. However, they are low in nutritional value. Food industries actively trying to find ways to reduce the fat content while maintaining organoleptic properties of fried foods. In this work, effects of pre-drying and adding food gums on the moisture and fat contents of chips were evaluated. The chips were pre-dried for 60 and 90 min, and gellan gum, guar gum, methylcellulose and xanthan gum were added at the concentration of 0.25, 0.75, 1 and 2 % w/w. The xanthan gum was the most effective gum for fat reduction. The addition of 0.25 % w/w xanthan gum and at 90 min pre-drying reduced the fat content from 20 % (control) to 15 % w/w. The results also indicated that the reduction of moisture content after frying was not affected by the type of gums but the method of pre-drying.