Showing papers on "Gum arabic published in 2011"

Effect of carrier type and spray drying on the physicochemical properties of powdered and reconstituted pomegranate juice (Punica Granatum L.)

Abstract: Pomegranate juice was diluted to 12° Brix and carriers (maltodextrin, gum Arabic, waxy starch) were added with varying concentrations of cellulose before being reduced to powder by spray drying. All carrier concentrations improved dryer yield, with gum Arabic being the most effective. The bulk density of the powder decreased when higher carrier concentrations were used. As cellulose concentration increased in solution, the solubility of the final product decreased. The optical properties of the powder were affected by the type and concentration of the carrier; powders produced with gum Arabic showed the greatest color change. Adding a carrier increased the Tg of the powder and its storage stability. Variation in the anthocyanin may be related to the type of carrier agent and its behavior during spray drying.

Carotenoid retention and storage stability of spray-dried encapsulated paprika oleoresin using gum Arabic and Soy protein isolate as wall materials

Abstract: The performance of gum arabic (GA) and soy protein isolate (SPI) on paprika oleoresin microcapsules preparation and their storage were evaluated. Paprika oleoresin emulsions with a ratio of paprika oleoresin/wall material of 1:4 (w/w) were prepared using high-pressure homogenization, and then spray dried. Both treatments showed that carotenoid retention in the microcapsules increased as inlet air temperature was increased from 160 to 200 °C, and the yellow fraction was more stable than the red fraction at all temperatures tested. Microcapsules with the highest carotenoid retention were stored at different aw’s at 35 °C. Maximal stability for carotenoid oxidation was found at aw’s of 0.274 and 0.710 for microcapsules prepared with GA and SPI respectively. In both treatments the lowest carotenoid degradation was associated to the minimum integral entropy zone and affected in the same way to the red and yellow pigments, during storage at 35 °C. Additionally, in contrast to microcapsules prepared with SPI, GA microcapsules were unable to retain their structural integrity at water activities above 0.743.

Assessment of production efficiency, physicochemical properties and storage stability of spray-dried chlorophyllide, a natural food colourant, using gum Arabic, maltodextrin and soy protein isolate-based carrier systems

Abstract: Summary The aim of this research was to study spray drying as potential action to protect chlorophyllide from environmental conditions for shelf-life extension and characterisation of the powders. Six formulations were prepared with 7.5 and 10 g of carrier agents [gum Arabic (GA), maltodextrin (MA) and soybean protein isolate (SPI)] ⁄ 100 mL of chlorophyllide solutions. The powders were evaluated for morphological characteristics (SEM), particle size, water activity, moisture, density, hygroscopicity, cold water solubility, sorption isotherms, colour and stability, during 90 days. All the powders were highly soluble, with solubility values around 97%. A significant lower hygroscopicity was observed for GA powders, whilst the lower Xm values obtained by GAB equation fitting of the sorption isotherms was observed for the 7.5 g MA ⁄ 100 mL samples. All formulations, but the 1 (7.5 g SPI ⁄ 100 mL of chlorophyllide), provided excellent stability to the chlorophyllide during 90 days of storage even at room temperature.

Effect of emulsifier on poly(urea–formaldehyde) microencapsulation of tetrachloroethylene

Abstract: Microcapsules containing tetrachloroethylene as an internal phase were prepared by in situ polymerization of urea–formaldehyde (UF) without prepolymerization The effects of different emulsifiers on the process of microencapsulation and morphology of microcapsules were investigated The results show that the emulsifier gum arabic (GA) can effectively slow down the deposition rate of resin onto the oil/water interface, which can lead to smooth and compact surface of microcapsules The surface activity of GA was also enhanced by complex formation of gum arabic and sodium dodecyl benzene sulfonate The microcapsules represent good thermal and barrier property as a result of the formation of capsule wall with compact microstructure

Gum acacia as a facile reducing, stabilizing, and templating agent for palladium nanoparticles

Abstract: This article presents the findings of a facile and effective nanoparticle synthesis approach based on aqueous solutions of gum acacia (GA), also known as gum arabic without the addition of any toxic reagents either for the reduction or capping for the effective stabilization of palladium (Pd) nanoparticles with a narrow size distribution (with a H 2 PdCl 4 /GA ratio of 1:29.411, the solution the average diameter was 9.1 nm, and the standard deviation was ±0.3 nm). In this approach, the particle size was controlled by the manipulation of the temperature, time, and concentration of GA. The synthesized Pd nanoparticles were well characterized by ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, dynamic light scattering, and thermogravimetric analysis. This route was very simple and reproducible, and further study on the application of these nanoparticles for various organic transformations is underway.

Effect of arabic gum and xanthan gum on the stability of pesticide in water emulsion.

Abstract: The effect of arabic gum (AG) and xanthan gum (XG) on the physicochemical properties of 2% pesticide avermyctin in water emulsions was systematically investigated by measuring creaming stability, droplet size, zeta potential, and rheology. Addition of AG and XG had significant influence on the physicochemical properties of emulsions. Emulsions showed high stability throughout the storage time in the AG concentration range of 0−0.14%. In contrast, addition of XG induced the apparent creaming of emulsion as the XG concentration increased from 0.011 to 0.15%, which might be well explained by the depletion flocculation of droplets. The droplet diameter increased progressively with increasing AG concentration; however, it sharply grew initially with XG concentration and reached a maximum, followed by a gradual decrease. Zeta potential increased gradually as AG concentration was lower than 0.081%, followed by a slight decrease, whereas it reduced dramatically as XG concentration increased from 0.011 to 0.040% a...

Effect of ultrasonic treatment on the rheological properties and particle size of gum tragacanth dispersions from different species

Abstract: Dispersions of different species of gum tragacanth were sonicated at a frequency of 24 kHz with a total nominal output power of 200 W for different time intervals (0, 7, 15, 45 and 90 s). Various species behave differently under sonication, which is related to structural differences in these species. In the case of Astragaslus compactus and A. rahensus dispersions, as the sonication time increased, the viscosity and particle size of the dispersions decreased, just as in gum Arabic solutions. However, A. gossypinus gum behaved differently compared to the other species. At early stages of sonication (up to 15 s), the viscosity of the dispersions increased sharply and reached its maximum value (106.04 mPa s) as the particle size increased slightly to 275.69 μm. Continuing sonication led to a decrease in the viscosity of the dispersions, though the particle size did not show any changes. This behaviour is thought to be due to the rupture and aggregation of particles.

Anti-malarial effect of gum arabic

Abstract: Background Gum Arabic (GA), a nonabsorbable nutrient from the exudate of Acacia senegal, exerts a powerful immunomodulatory effect on dendritic cells, antigen-presenting cells involved in the initiation of both innate and adaptive immunity. On the other hand GA degradation delivers short chain fatty acids, which in turn have been shown to foster the expression of foetal haemoglobin in erythrocytes. Increased levels of erythrocyte foetal haemoglobin are known to impede the intraerythrocytic growth of Plasmodium and thus confer some protection against malaria. The present study tested whether gum arabic may influence the clinical course of malaria.

Effects of Gum acacia aqueous extract on the histology of the intestine and enzymes of both the intestine and the pancreas of albino rats treated with Meloxicam.

Abstract: Background: Non-steroidal anti-inflammatory drugs (NSAIDs) cause gastrointestinal damage both in the upper and lower gastrointestinal tract, in addition to their undesirable side effects on the pancreas. Meloxicam like all NSAIDs has damaging effects on the gastrointestinal tract including perforations, ulcers and bleeding. Objective: The present work describes the effects of Gum acacia aqueous extract on the histology of intestine and enzymes of both intestine and Pancreas of albino rats treated with Meloxicam. Materials and Methods: This study was performed on four groups of equally weighed male rats, each group included ten animals; the first group was received a diet containing 0.2 mg/kg bw meloxicam per day; the second was given 1gm Gum acacia per day in its diet; the third was given meloxicam followed by gum in the same doses per day; while the fourth group (control rats) was placed on a normal diet and water. All rats were received their diet for a period of 21 days. Results: A considerable protective effect of Gum acacia aqueous extract on the histology of intestine of albino rats treated with meloxicam was recorded. In addition, the study displayed a significant increase (P < 0.001) in the intestinal enzymes; lipase, amylase, alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) in the 1 st and 3 rd groups animals while these enzymes were significantly decreased (P < 0.001) in the 2 nd group when compared with the 4 th control group. Conclusion: This study concluded that Gum acacia provides a protection and defense against the harmful effects of meloxicam therapy used as one of the novel anti-Cox-1 and Cox-2 NSAIDs.

Application of gum arabic for coating of dried mango slices.

Abstract: Mango (Mangifera indica) fruit of kitshenar variety which is grown in wide areas in Sudan was used in this study to investigate the effect of processing treatment and storage period on the quality of dried mango slices (finger). Mango fruits of kitshenar variety were washed carefully, peeled manually and then sliced into (fingers). Mango slices were divided into three portions, the first portion coated with (25% w/v) Gum Arabic purified solution plus (5% w/v) sugar, the second portion was treated with sodium metabisulphite solution 2000 p.p.m concentration and the third portion was left without any treatment (control). Mango slices of each treatment were speeded on aluminum trays with an equal distribution and dried at room temperature under moving fan for seven days and then the dried products were packed in (polythene) plastic socks then placed inside cartoons and stored at room temperature for nine months. The results showed that the treatment with sodiummetabisulphite solution was the best in keeping the nutritive value of mango slices (ascorbic acid). The results indicated that the best treatment which prevented browning was Gum Arabic addition. The study of the effect of storage periods at room temperature on some properties of mango slices (fingers) showed there was a marked loss of some nutrients (e.g. ascorbic acid, sugars).

Structural Characteristics and Functional Properties of Gum Arabic

Abstract: Gum arabic occurs as a sticky liquid that oozes from the stems and branches of acacia trees, which grow across the Sahelian belt of Africa. Although there are probably over 1000 species of acacia it is only the gum from Acacia senegal and Acacia seyal that can be referred to as gum arabic. The liquid dries in the sun to form glassy nodules, which are collected by hand by local farmers. The gum has been an article of commerce for more than 5000 years and was used by the Ancient Egyptians for producing paints and for coating the flaxen wrappings used to embalm mummies. Nowadays, its main applications are in confectionery to control texture and inhibit sugar crystallisation and in beverages as an emulsifier and encapsulator for flavour oils.

Analysis of thickening polysaccharides by the improved diethyldithioacetal derivatization method

Abstract: The identification test for thickening polysaccharides containing neutral saccharides and uronic acids was investigated by GC analysis of constituent monosaccharides. The reported method, in which monosaccharides were converted to diethyldithioacetal derivatives with ethanethiol followed by trimethylsilylation, was improved in terms of operability and reproducibility of GC/MS analysis. The suitability of the improved diethyldithioacetal derivatization method was determined for seven thickening polysaccharides, i.e., carob bean gum, guar gum, karaya gum, gum arabic, gum ghatti, tragacanth gum and peach gum. The samples were acid-hydrolyzed to form monosaccharides. The hydrolysates were derivatized and analyzed with GC/FID. Each sugar derivative was detected as a single peak and was well separated from others on the chromatograms. The amounts of constituent monosaccharides in thickening polysaccharides were successfully estimated. Seven polysaccharides were distinguished from each other on the basis of constituent monosaccharides. Further examination of the time period of hydrolysis of polysaccharides using peach gum showed that the optimal times were not the same for all monosaccharides. A longer time was needed to hydrolyze glucuronic acid than neutral saccharides. The findings suggest that hydrolysis time may sometimes affect the analytical results on composition of constituent monosaccharides in polysaccharides.

Rheological Properties of Gum Arabic Solution: the Effect of Arabinogalactan Protein Complex (AGP)

Abstract: Gum arabic solution is generally regarded as a Newtonian liquid with an anomalous low viscosity. However, recent research on the rheological properties of gum arabic in water has shown that it is not simply Newtonian. In this work, rheological properties of gum arabic solutions were investigated, with emphasis on its non-Newtonian behaviour of shear thinning and thixotropy, and interpreted based on molecular association in the solution. It was found that the arabinogalactan protein complex (AGP) in gum arabic might be the main source of molecular association though it only represents about 10% of the total gum. The occurrence of AGP micelles endowed the gum arabic solution with non-Newtonian behaviour of shear thinning and thixotropy. This fact was evidenced by using single-walled carbon nanotubes (SWNTs) to trap AGP. The non-Newtonian behavior of gum arabic solution vanished after AGP was removed from the solution.

Effect of AGP on Emulsifying Stability of Gum Arabic

Abstract: Gum arabic (Acacia senegal) is an important natural oil-in-water emulsifier, which is widely used in the food industry. However, emulsification performance of natural gum arabic greatly varies depending on origin, production area, tree age, the weather and changes in arabinogalactan protein (AGP) content during storage. The correlation between AGP components and emulsifying stability has been studied in detail using natural gum arabic. Molecular weight and AGP content were analysed using GPC-MALLS (Gel permeation chromatography – multi-angle laser light scattering) and emulsifying stability was evaluated by measuring the particle size of test emulsions after accelerated storage. AGP content of natural gum arabic varies greatly. Gum arabic with a higher AGP content has a higher emulsifying stability, whereas gum arabic with a lower AGP content has a lower emulsifying stability. It is very important for emulsion users to have access to a supply of high performance natural gum arabic with a higher and consistent AGP content.

Effect of in vitro human digestion on the viscosity of hydrocolloids in solution: A dietary fibre study

Abstract: EFFECT OF IN VITRO HUMAN DIGESTION ON THE VISCOSITY OF HYDROCOLLOIDS IN SOLUTION: A DIETARY FIBRE STUDY Hrvoje Fabek Advisor: University of Guelph, 2011 Professor H.D. Goff The effects of a simulated in vitro digestion model on the viscosity of solutions of locust bean gum, guar gum, fenugreek gum, xanthan gum, gum Arabic, psyllium, flaxseed gum and soy soluble polysaccharides (SSPS) were examined in this study. All hydrocolloid solutions were formulated for low viscosity (LV), medium viscosity (MV) and high viscosity (HV), which were subsequently subjected to 3 treatments of equal volumes each. The treatments consisted of 1) H2O-dilutions, 2) acid and alkali in the absence of enzymes/bile and 3) an in vitro digestion model simulating the gastric and duodenal phases with pH changes in the presence of hydrolytic enzymes and bile salts. All hydrocolloids showed substantial reductions in viscosity, with dilutions exerting the greatest effect. Depending on the concentration, xanthan gum retained 20-50% of its initial viscosity while the other solutions were in a lower range of 1-16%, thereby showing considerable resilience to the 3 simulated conditions.

Gum Arabic's (Gum Acacia's) Journey from Tree to End User

Abstract: Gum acacia, also known as gum arabic, is exuded from Acacia trees - mainly from Acacia senegal and Acacia seyal. The main gum acacia producing countries are Sudan, Nigeria, Chad and Senegal. Sudan is considered to be the world's largest producer of gum acacia. Gum acacia is the oldest and best known of all the polysaccharide plant exudates.

Agent for improving untangling of noodle, and method for improving untangling of noodle

Abstract: PROBLEM TO BE SOLVED: To provide an agent for improving the untangling of noodles without damaging the appearance, taste and texture of the noodles, and having high fluidity and good operability, and to provide a method for improving the untangling of the noodles by using the agent. SOLUTION: The agent for improving the untangling of the noodles comprises an aqueous solution of 0.5-4.5 wt.%, 0.5-4.0 wt.% and 0.5-2.5 wt.% of gum arabic, gum ghatti and one or more kinds of emulsifying agent components respectively, and the remainder of water, and has 1-35 mPa s of the viscosity at 5-20°C of the temperature. COPYRIGHT: (C)2011,JPO&INPIT