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1.
In the present study, gum combinations used in the pudding formulation were optimized by mixture design approach based on creep and recovery measurements. For this aim, four different gums (carrageenan, alginate, guar and xanthan gum) and their different combinations were used in the formulation. The creep-recovery properties of the pudding samples prepared with different gums or gum combinations were investigated. Burger model was satisfactorily applied for the determination of the creep-recovery characteristics of the samples. The use of the carrageenan in the pudding formulation caused a decrease in deformation of the samples. Gel strength value of the pudding samples was also calculated using the data. In order to optimize the gum combination based on the creep-recovery measurements, mixture design was carried out, and it was seen that established models satisfactorily predicted the viscoelastic parameters of the samples. During the optimization of the gum combination used in the pudding formulation, desirability function was used to optimize the ingredients simultaneously based on the requirements. The gum combination including 59.5 % carrageenan and 40.5 % guar gum or 52.7 % carrageenan, 33.8 % guar gum and 13.5 % xanthan gum was determined to be the optimum in terms of quality of the product.  相似文献   

2.
《Food chemistry》1999,67(3):217-222
Water soluble gums were extracted from seeds of achi (Brachystegea eurycoma) and Ogbono (Irvingia gabonesis). The rheological properties of each gum were studied at temperatures from between 10–70°C at 1.0, 1.5, 2.0, and 2.5% concentrations. The effects of small quantities of the gums on some of the quality characteristics of an ice cream mix were investigated. These characteristics were compared with those of some commercial food gums, carboxymethyl cellulose (CMC), Kappa carrageenan (KCA), and sodium alginate (SA). The viscosities of both gums were time-independent and Ogbono seed gum (OSG) appeared to be more pseudoplastic than Achi seed gum (ASG). The pseudoplastic nature was not affected by increasing temperature. The temperature control was more critical for OSG (Ea. 20.2 MJ mol−1) than ASG (Ea 13.9 MJ mol−1) during processing. The viscosity behaviour of ASG indicates that it may be a highly branched polysaccharide. The overrun, viscosity, shapefactor and meltdown values of the ice cream, when ASG was added as stabilizer, were 95%, 0.035 PaS, 72% and 32%, respectively. Values for OSG were 70%, 0.025 PaS, 65% and 37.7%, respectively. Only values for the ASG cream fell within the ranges of values obtained for the commercial gums. ©  相似文献   

3.
Crude fenugreek gum (3.74% protein) was purified by dissolving in aqueous solvent and centrifugation to remove impurities which yielded a purified gum fraction containing 1.10% protein residue. Further purification of the gum was achieved by treating the gum solution with phenol to obtain protein free fenugreek gum (0.16% protein residue). The three types of fenugreek gums were evaluated for: molecular weight, surface activity and rheological performance. Surface and interfacial tension, measured by a Du Nouy ring, indicated that the removal of protein in the gum significantly reduced its surface activity. However, the crude fenugreek gum exhibited lower intrinsic viscosity and radius of gyration compared to the purified and protein free fenugreek gums. It was found that both protein residue and gum concentration affected the elastic modulus (G′), viscous modulus (G″), and complex viscosity (η*).  相似文献   

4.
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.  相似文献   

5.
Rheological properties of gluten-free bread formulations   总被引:1,自引:0,他引:1  
In this study, the rheological properties of rice bread dough containing different gums with or without emulsifiers were determined. In addition, the quality of rice breads (volume, firmness and sensory analysis) was evaluated. Different gums (xanthan gum, guar gum, locust bean gum (LBG), hydroxyl propyl methyl cellulose (HPMC), pectin, xanthan–guar, and xanthan–LBG blend) and emulsifiers (Purawave and DATEM) were used to find the best formulation for gluten-free breads. Rice dough and wheat dough containing no gum and emulsifier were used as control formulations. The rice dough containing different gums with or without emulsifiers at 25 °C showed shear-thinning behavior with a flow behavior index (n) ranging from 0.33–0.68 (except pectin containing samples) and consistency index (K) ranging from 2.75–61.7 Pa sn. The highest elastic (G′) and loss (G″) module were obtained for rice dough samples containing xanthan gum, xanthan–guar and xanthan–LBG blend with DATEM. When Purawave was used as an emulsifier, dough samples had relatively smaller consistency index and viscoelastic moduli values compared to DATEM. The viscoelastic parameters of rice dough were found to be related to bread firmness. Addition of DATEM improved bread quality in terms of specific volume and sensory values.  相似文献   

6.
We present for the first time the interactions of starch and cassia gum – a novel galactomannan recently approved for use in food processing. Viscoelastic, pasting and microstructural characterization of various starches (waxy; high amylose; normal; cross-linked waxy corn starch; potato starch) containing different levels of the cassia gum was carried out. Significant changes were observed in the morphology of granule remnants formed during gelatinization in the starch pastes prepared with and without the addition of cassia gum. The freeze-dried starch–cassia gum pastes presented a shrunken and tight arrangement of the starch granule remnants, when studied by scanning electron microscopy. A significant reduction in the granule remnant size was also calculated using laser diffraction particle size analysis. The extent of interaction with cassia gum differed significantly among the various starch types. All the unmodified corn starches recorded an increase in peak viscosity at all levels of the cassia gum addition. An increase in the final viscosity of these starches was also observed by the addition of cassia gum, with high amylose and normal corn starch showing the maximum. Similarly, the extent of breakdown and setback viscosity also differed among the different starch types. Ranges of dynamic rheological measurements (temperature, time and frequency sweeps) were performed within the viscoelastic zones. Rheological parameters, such as storage modulus (G′), loss modulus (G″) and the gelatinization temperature (Tgel), of the corn starches during the heating cycle were observed to increase, when cassia gum was present at lower levels. The starch–gum systems also exhibited higher tan δ values during both the heating and the cooling cycles, indicating the dominance of the viscous modulus. The G′ and G″ of all the corn starch gels containing cassia gum showed higher values throughout the frequency sweep range. However, the increase in G′ and G″ of different starches was not always consistent with the increase in cassia gum levels. The changes in rheological behaviour during storage of the starch gels, aged on the plate of the rheometer and then studied through time sweeps at 5 °C and frequency sweeps at 25 °C, suggested that the starch gels containing cassia gum had less pronounced changes in the rheological parameters than had their control counterparts.  相似文献   

7.
This study examined the steady flow and dynamic rheological behaviors of hydroxypropylated sweet potato starch (HPSPS) pastes mixed with guar gum (GG), locust bean gum (LBG), and xanthan gum (XG) at different concentrations (0, 0.3, and 0.6%). The HPSPS–gum mixtures had higher shear‐thinning fluid characteristics than the control (0% gum) at 25°C. The addition of the gums resulted in an increase in the consistency index (K) and apparent viscosity (ηa,100). The dynamic moduli (G′, G″) and complex viscosity (η*) values of the HPSPS–gum mixtures were higher than those of the control, and they increased with an increase in gum concentration. In particular, the presence of XG at 0.6% in the HPSPS–gum mixture systems gave rise to the greatest viscoelastic properties among the gums examined at different concentrations. The tan δ (ratio of G″/G′) values (0.35–0.57) of the HPSPS–GG and HPSPS–XG mixtures were much lower than those of the control (0.82) and HPSPS–LBG (0.88–1.06), indicating that the elastic properties in the HPSPS–gum mixture systems were strongly affected by the additions of GG and XG. These steady flow and dynamic rheological parameters indicated there were synergistic interactions between the HPSPS and gums. The synergistic effects of the gums and modified starch were hypothesized by considering the molecular incompatibility and molecular interactions between the gums and HPSPS.  相似文献   

8.
This research investigated the multi-scale characteristics of potato starch gel (PSG) with different addition ratios of xanthan gum (XG) and locust bean gum (LBG). These characteristics are closely related and had significant impacts on 3D printing performance. Both xanthan gum and locust bean gum were able to increase the apparent viscosity, storage modulus (G′) and loss modulus (G″) of the blended gel system to varying degrees. Large amplitude oscillation shear (LAOS) was used to detect slight rheological differences led by microstructure changes. The critical strain values of the blended gel system rose as the addition ratio of locust bean gum increased. At the same time, the elastic and viscous Lissajous curves could characterize the viscoelastic changes under large strains. Fourier transforms infrared spectroscopy (FT-IR) illustrated that locust bean gum could strengthen the hydrogen bonds so that the gel had stronger mechanical properties compared with the addition of xanthan gum. Scanning electron microscopy (SEM) could observe the changes in the microstructure of the blended gel systems with addition of different addition ratios of gums. From the perspectives of 3D printing results and data analysis, the appropriate amount of xanthan gum improved the fineness and fluidity of the gels by virtue of its lubricating and coating characteristics, while the locust bean gum enabled them to have stronger shape retention abilities and better performances of resisting compressed deformation.  相似文献   

9.
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.  相似文献   

10.
Temperature sweep tests and steady shear properties of five different food hydrocolloids (guar gum, xanthan gum, carboxymethylcellulose, pectin and carrageenan) in two different particle sizes groups have been determined at 25, 40, 60 and 80 °C in 1% aqueous solution. Also, the Scanning Electron Microscopy (SEM) images of gums were taken to investigate the morphological properties of the samples. The particle size and processing temperature significantly affected all rheological parameters of the hydrocolloid solutions. The flow behavior of the samples was fitted to Ostwald de Waele model (R2?=?0.959). The highest n value was recorded at 60 °C for all samples. The most drastic changes in consistency coefficient (K) values of the samples were observed in carrageenan solution and it was ranged from 0.013 to 1.774 Pa.sn before the size reduction and from 0.007 to 0.337 Pa.sn after the size reduction process. As the consistency coefficient (K) and apparent viscosity (η50) decreased with the temperature, the flow behavior index increased in both group of samples. As a result, it was concluded that the increase in processing temperature and size reduction process caused a decrease in resistance of hydrocolloid solutions subjected to the deformation, which is a very important factor affecting the quality and good mouth-feel of products.  相似文献   

11.
The aim of the study was to define the influence of selected nonstarch polysaccharides (guar gum, xanthan gum and arabic gum) on several rheological properties of triticale starch pastes/gels, at constant polysaccharide concentration (6.5 g/100 g). These included pasting characteristics, flow curves at 50 °C and mechanical spectra at 25 °C. It was found that the presence of a gum in a system modified the rheological properties of triticale starch gels/pastes, depending on the type and concentration of the gums. In the case of guar and xanthan gums, higher pasting viscosity was observed and the shear stress was increased compared with native starch. The presence of guar gum reduced the degree of thixotropy hysteresis, negative values for this being found for systems with xanthan in spite of their shear‐thinning behaviour. Systems containing arabic gum displayed lower values of pasting and flow viscosity. The type and concentration of gums added to the polysaccharide influenced the viscoelastic properties of the gels.  相似文献   

12.
Effect of hydrocolloids such as guar gum (GG), arabic gum (AG), carrageenan (CG), locust bean gum (LBG), xanthan gum (XN), hydroxypropyl methylcellulose (HPMC) and carboxymethylcellulose (CMC) at 0.5% w/w level on rheological and quality parameters of puri from whole wheat flour was studied. Hydrocolloids like CMC, XN and HPMC increased the water absorption of puri dough, while it decreased in all other samples. The dough development time and mixing tolerance index values increased, while dough stability did not get affected. On addition of hydrocolloid, there was a reduction in the pasting temperature, while the peak viscosity, hot paste viscosity and cold paste viscosity values increased. Hardness, cohesiveness and adhesiveness properties of the puri dough increased with the addition of hydrocolloids. All the hydrocolloids used in general helped in retention of moisture in the puri and hence remained softer and pliable, while there was a significant reduction in the oil content of puri samples containing hydrocolloids. Among the different hydrocolloids used, addition of guar gum at 0.5% w/w level led to puris having improved quality characteristics to a greater extent with respect to moisture retention, lowering of oil content upon frying with softer and pliable texture and better keeping quality. The mass transfer studies confirmed that the mass transfer co-efficient values for moisture loss and oil uptake were lower in puris with guar gum than control.  相似文献   

13.
The rheological properties of mayonnaise containing alginates from Macrocystis pyrifera as stabilizers were studied using a controlled stress rheometer and a texture analyser penetrometer. Dynamic oscillatory tests of the emulsions were carried out in strain sweep and frequency sweep modes. The rheological parameters used for this study were the storage (G′), loss (G″) and complex (G*) moduli and the strain, which determined the limit of the linear viscoelastic region (γc). The effect of alginate concentration (0.2, 0.5 and 0.8 g/100 g) and molecular weight (MW: 76, 120 and 154 kDa) on physical properties was examined and the best combination useful to minimize differences between the alginate emulsion and mayonnaise with modified corn starch as commercial reference was identified (0.35 g/100 g and 108 kDa). The storage modulus increased with alginate content and it became independent of the molecular size above a critical value between 76 and 120 kDa. A positive effect of MW on γc was observed at 0.2 g/100 g alginate and the critical strain decreased with increasing polymer concentration up to 0.5 g/100 g. Results under small-amplitude oscillatory shear tests (linear viscoelastic properties) were interpreted in the context of the weak gel model. Two material parameters were determined to describe the rheological structure of the emulsion: the coordination number (z) and the parameter A (G* at 1 Hz). Mayonnaises with alginate concentrations of 0.5 and 0.8 g/100 g and at all the MW had coordination numbers which were not significantly different from those of the reference sample. The emulsion strength of alginate samples with polymer concentration of 0.5 and 0.8 g/100 g was significantly higher than the control.  相似文献   

14.
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  相似文献   

15.
Sterilized dairy desserts were prepared using five ingredients: κ-carrageenan, skimmed milk powder, adipate cross-linked acetyl substituted waxy maize starch, sucrose and water. An experimental mixture design was used to study the influence of varying concentrations of carrageenan, milk powder and starch on the dessert properties, while the sucrose and water content was kept constant. Starch was shown to have a larger influence on the complex modulus, while milk powder contributed more to the gel strength of the desserts, determined by a penetration test. Also, increasing amounts of carrageenan and starch led to a decrease in the occurrence of syneresis. Results seem to suggest that the interaction between casein and carrageenan, that is well described for model systems, also takes place in sterilized dairy desserts and that the rheological properties are importantly affected by the exclusion effect of starch.  相似文献   

16.
The viscosity of pure and mixed dilute solutions of commercial alginate, carrageenan, guar gum, CMC and gelatin solutions at different mixing ratios were measured by a coaxial viscosimeter at different shear rates. The results are presented in the form of measured viscosity divided by the expected viscosity, if no interaction between the gums existed. This technique provides a clear demonstration of the existence of synergism or antagonism between the gums and helps in quantitatively assessing their extent.  相似文献   

17.
The aim of this project was to prepare high-fiber pudding using date pits to meet the FDA requirement for health claim. Pudding desert was prepared with dates pits (DP), starch, sugar, xanthan gum (DX), flaxseeds gum (DF), and powdered milk. DP were milled, sieved through 149-µm sieve, and used for formulating high-fiber pudding. The pudding formulation included yeast, DX, or DF, and without gum (DP). Danette chocolate pudding, a commercial sample, was used as a reference. The formulation was cooked using rapid visco analyzer (RVA), and the gel was further analyzed by Brookfield viscometer and texture analyzer. The RVA profile of the formulation included peak viscosity, setback, and final viscosity. The data obtained from the RVA showed that pudding samples containing DX or DF gums exhibited higher peak viscosities (3,012.7 ± 22.5, 1,236.3 ± 110.9 cP, respectively) as compared to the DP pudding 735.3 ± 38.3 cP. The presence of DX instigated higher gel hardness than DF and DP, whereas DF caused higher cohesiveness than DP and DX. The shear stress as a function of shear rate profile indicated that DF was closer to Danette pudding sample. The consistency coefficient index (K), which was obtained from the power law, was higher for both DX and DF, indicating higher viscosity, whereas lower flow behavior index (n) signifies a more pseudoplastic system of these samples. Based on the Ea values, it can be concluded that DX sample is less temperature dependent (lower Ea) than DF (higher Ea). The sensory testing showed that yeast treatment brought the formulation closer to the control in terms of panel acceptance.  相似文献   

18.
Gums are integral ingredients in fluid foods used for controlling viscosity and mouthfeel. Advances in rheological instrumentations permits enhanced evaluations of the viscoelastic properties of fluids. Rheological properties of twelve gum solutions were investigated at concentrations of 0.05%, 0.1%, and 0.5%. The viscous (η″) and elastic (η″) components of the complex viscosity η1, elastic yield stress, and tan δ were measured as functions of oscillatory shear. Konjac exhibited the highest η′ and η″ components among all gums at 0.5% and 50 s−1. Gum Arabic, methylcellulose and pectin, exhibited the least η′ and no η″ component under the same conditions. Konjac exhibited greatest elastic yield stress, whereas microcrystallinecellulose had the least. Modeling results showed that rheological properties of CMC were characterized by an exponential relationship, whereas riota-carrageenan and xanthan were described by a power type relationship. A substantial increase in tan δ was observed for most 0.5% gums solutions at shear rates beyond 10 s−1, indicating a shift from a visco-elastic regime to a purely viscous one. For gums that showed substantial visco-elasticity, peak tan δ values ranged from 5.7 to 68.3.  相似文献   

19.
侯大军  李洪军 《食品科学》2009,30(13):140-142
探讨以猪肉为原料的西式火腿加工过程中,食用胶加入的种类、加入方式和加入量对产品物性的影响,并采用正交试验研究不同食用胶在西式火腿中的应用效果。结果表明,卡拉胶的加入对西式火腿的黏着性、凝聚性、弹性均有较好影响,当以单一的食用胶添加在西式火腿中时,使用卡拉胶且以粉状的方式添加以及添加量为0.3% 时的效果为最佳。  相似文献   

20.
研究了离子胶(羧甲基纤维素钠、海藻酸钠、卡拉胶、壳聚糖)不同添加量(0∶1、1∶9、3∶7)对玉米磷酸酯双淀粉糊化特性、凝胶质构特性、溶胀度和吸油率等性质的影响。结果表明,阴离子胶(羧甲基纤维素钠、海藻酸钠、卡拉胶)降低了玉米磷酸酯双淀粉的峰值黏度、衰减值;而阳离子胶(壳聚糖)使玉米磷酸酯双淀粉的峰值黏度、衰减值显著增加。阴离子胶使玉米磷酸酯双淀粉凝胶硬度下降,而壳聚糖则使其凝胶硬度上升。阴离子胶能促进玉米磷酸酯双淀粉的溶胀,但壳聚糖抑制其溶胀。壳聚糖使玉米磷酸酯双淀粉吸油率增加。离子胶对玉米磷酸酯双淀粉性质的影响,不仅与离子胶自身性质有关,而且可能与二者之间的静电作用密切相关。  相似文献   

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