Screening of hydrocolloids for reduction in oil uptake of a model deep fat fried product

Reduction of oil content in deep fat fried foods would be welcome by both the food manufacturers and the consumers. Among the many approaches that have been evaluated for this purpose, use of hydrocolloid additives is believed to be most promising. Work in this area is restricted mostly to cellulose derivatives. The mechanism of action of these derivatives is attributed to formation of an oil resistant barrier film, an alteration in surface hydrophobicity of the product being fried, and the thermal gelation. However, most hydrocolloids would alter the surface hydrophobicity, and many of them have the ability to form films. Furthermore, the presence of other food constituents can alter all these properties. Hence, hydrocolloids at 0.25— 2.00 % (on the basis of chickpea flour) were screened for their ability to reduce oil uptake in sev, a model deep fat fried product prepared from chickpea flour. Results obtained indicate that the ability to reduce oil uptake in this product decreases in the following order: gum arabic > carrageenan > gum karaya > guar gum > carboxymethylcellulose > hydroxypropylmethyl cellulose. Hydrocolloids such as xanthan, gum ghatti, gum tragacanth, and locust bean gum were found to be ineffective (<10 % reduction in the oil content) for this purpose.     

Study of oil uptake and some quality attributes of potato chips affected by hydrocolloids

The use of coating agents is one effective way to reduce oil absorption in fried products. Reducing the fat content of fried foods by application of coatings is an alternative solution to comply with both health concerns and consumer preferences. The aim of this study was to analyze the effect of hydrocolloids as coating agent on the quantity of oil uptake and on sensory attributes of potato chips. The effect of the coating composition showed that the minimum fat content was related to 1% carboxymethyl cellulose (CMC), 0.5% xanthan, 0.3% guar and 1% xanthan with 21.2, 21.7, 22.4 and 24.8%, respectively, and the highest of fat content was related to blank sample (non-coated), 2% tragacanth, 0.5% guar gum with 49.4, 41.7 and 33.2% of oil content, respectively (p <0.05). The most effective coating agent reduced the oil uptake by 57.03, 55.94, 54.67 and 49.71%, respectively (p <0.05). Sensory evaluation showed that the best color was related to 1% CMC, 0.3% guar and 2% tragacanth, and with respect to flavor evaluation the best flavor was observed in tragacanth 2%, CMC 0.5% and CMC 0.1%, and the best texture referred to tragacanth 2%, CMC 0.5% and CMC 1%. In sensory evaluation, all coated chips got high scores compared with blank (non-coated chips) samples (p <0.05).     

Preparation of microcapsules of W/O/W emulsions containing a polysaccharide in the outer aqueous phase by spray‐drying

A water‐in‐oil‐in‐water (W/O/W) multiple emulsion containing a hydrophilic substance, 1,3,6,8‐pyrenetetrasulfonic acid tetrasodium salt (PTSA), and a wall material in its inner and outer aqueous phases, respectively, was prepared by a two‐step emulsification using a rotor/stator homogenizer, and was further homogenized with a high‐pressure homogenizer. Maltodextrin or gum arabic were used as wall materials, and olive oil was used as the oily phase. The high encapsulation efficiency for PTSA (>0.9) was realized. The emulsion was spray‐dried to produce microcapsules of W/O/W type. The efficiencies of the microcapsules prepared with maltodextrin and gum arabic were 0.82 and 0.67, respectively. Stability of the microcapsules was examined at 37 °C and 12%, 33% and 75% relative humidity. Microcapsules prepared with maltodextrin were more stable than those prepared with gum arabic.     

Titania/gum tragacanth nanohydrogel for methylene blue dye removal from textile wastewater using response surface methodology

The aim of this study was to statistically evaluate the capability of a prepared TiO₂/gum tragacanth hydrogel as a photocatalyst for the removal of methylene blue dye molecules from contaminated solutions. In this regard, TiO₂ nanoparticles were sonicated in gum tragacanth and the final hydrogel was prepared by the addition of glutaraldehyde as a crosslinking agent. Response surface methodology was employed as a mathematical and statistical tool to describe the system by a polynomial equation that relates the removal efficiency to selected variables (time, pH, initial dye concentration and photocatalyst dosage). The significance and adequacy of the model were confirmed by high coefficient of determination (R²) and adjusted R² values (>93%). The system was optimized at an initial dye concentration of 9.37 mg L^?1, pH of 9.02, time of 124.34 min and photocatalyst dosage of 0.13 g L^?1 using the response optimizer with an efficiency of 88.86%. A kinetic study of photocatalytic decoloration indicated that the pseudo‐second‐order model was well fitted to the experimental data. © 2018 Society of Chemical Industry     

Chemical modification of gum arabic and its application in the encapsulation of Cymbopogon citratus essential oil

Sodium trimetaphosphate (STMP) is an effective crosslinking agent of starch and can be used in other polysaccharides for promoting changes in their physical and chemical characteristics. In this study, gum arabic was modified with different STMP concentrations and evaluated as the changes in the physical and physicochemical characteristics. Further, modified gum arabic was evaluated by encapsulation efficiency (EE) of Cymbopogon citratus essential oil. A lower viscosity was observed with the increase of the STMP concentration. Higher concentrations of STMP decreased the water amount retained in the modified gum arabic. The increasing of the crosslinking degree causes a decrease in particle size. The EE of modified gum arabic with 6% STMP was 97%, whereas for the unmodified gum arabic was 85%. The high efficiency encapsulation of the essential oil is a positive result of physicochemical changes in the gum arabic crosslinking. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41519.     

UTILIZATION OF MESQUITE ( Prosopis julijlora) GUM AS EMULSION STABILIZING AGENT FOR SPRAY-DRIED ENCAPSULATED ORANGE PEEL OIL

Abstract

Orange peel oil was microencapsulated. Mesquite gum and its performance for producing spray-dried powders was compared to emulsions prepared with gum arabic. Average oil droplet size of mesquite gum capsules was smaller than that of gum arabic. Emulsions made with mesquite gum showed better stability than those made with gum arabic. Encapsulation capacity of mesquite gum was found to be 80.5 % of the starting oil whereas gum arabic was able to encapsulate 93.5 %. Sensory evaluation showed that there was not significant difference (α<0.05) in flavor intensity between orange peel oil encapsulated with the two emulsifiers.     

热敏材料微胶囊及热敏油墨的制备

用明胶 -阿拉伯树胶做壁材 ,热敏变色材料做心材制热敏材料微胶囊。阿拉伯树胶、明胶和心材三者质量比为 1∶1∶1,用甲醛固化壁材。固化前将体系调至pH =9。加入明胶质量 2 %的纳米级二氧化硅作隔离剂。与不加二氧化硅相比 ,加入二氧化硅后 ,彼此发生粘连的微胶囊数由占总数的 2 0 %降至 5 % .与不经包敷的热敏材料做的油墨相比 ,用热敏材料微胶囊做的油墨在 6 0℃下的储存期由 72h延长至 36 0h ;在 40℃由嫩黄色变成深桔红色前者需 4s,后者则需 3s;离开热源在 2 0℃室温下 ,前者 6s恢复原色 ,后者需 4s     

Tragacanth gum-graft-polyacrylonitrile: synthesis,characterization and hydrolysis

A large number of cyanide functional groups were introduced onto the carbohydrate biopolymer tragacanth gum to yield hydrophobic graft copolymer, tragacanth gum-g-polyacrylonitrile. Thus, graft copolymerization of monomer acrylonitrile (AN) was carried out under nitrogen atmosphere using ceric ammonium nitrate (CAN) as an initiator. The highest percentage of grafting (543%) and the lowest homopolymer content (10%) were achieved through a systematic optimization of the polymerization variables, including reaction time, temperature, and concentration of CAN, AN and the gum. Evidence of grafting was examined by comparing FTIR spectra. The optimally prepared tragacanth gum-g-polyacrylonitrile copolymer was also characterized thermally and morphologically. It was hydrolyzed in alkaline medium to achieve an in-situ crosslinked hybrid network with ultra high water absorption capacity (swelling in water, 30700%; swelling in saline, 6550%). The swelling characteristic of the semi-synthetic super-absorbent hydrogel was preliminarily investigated. The chemical structure, thermal characteristics and morphology of the hydrogel hybrid product were briefly studied.     

Preparation and characterization of poly(vinyl alcohol)/gum tragacanth/cellulose nanocomposite film

The effects of gum tragacanth obtained from two species of Astragalus Gossypinus (GT-G) and A. Parrowianus (GT-P) at two levels of 10% and 30% combined with cellulose nanofibers (CNF; 5%) on the physico-mechanical and structural properties of polyvinyl alcohol (PVA) nanocomposite film were investigated in this study. The water solubility and water vapor permeability of the films decreased with increasing the content of both gums, especially in the film containing 30% GT-P. The highest values of the tensile strength (39.3 MPa) and elongation at break (445%) belonged to the treatment containing 10% GT-P (90/10P/0). The FTIR and DSC analyses confirmed good interactions between GT and PVA in the 90/10P/0 treatment. SEM images indicated the dense structure of this film as the optimum treatment. Although the presence of CNF in the films containing GT-G improved some properties, especially the Young modulus, it impaired all the functional properties of nanocomposite GT-P film.     

Measurement of shear-dependent intrinsic viscosities of carboxymethyl cellulose and xanthan gum suspensions

A rotational rheometer with cone and plate fixtures was used to measure the intrinsic viscosities of aqueous suspensions of xanthan gum and carboxymethyl cellulose (CMC). The reduced viscosities or hydrodynamic volumes of CMC suspensions increased with dilution. However, the reduced viscosities of xanthan gum suspensions decreased with dilution within the concentration range of 0.1–0.06% and increased with dilution within the concentration range of 0.04–0.01%. When the gums were suspended and diluted with 0.06 M sodium acetate, the reduced viscosities of all the xanthan gum and CMC suspensions decreased upon dilution. The intrinsic viscosities of xanthan gum and CMC suspensions decreased with increasing the shear rate, showing a dependence of hydrodynamic volume on shear rate.     

Influence of wall material on production of spray dried Lactobacillus plantarum NRRL B-4496 and its viability at different storage conditions

The objectives of this study were to evaluate the spray drying conditions to produce Lactobacillus plantarum powders and to investigate their viability at different storage conditions. L. plantarum NRRL B-4496 was spray dried with high maize starch, maltodextrin, or gum arabic and stored under 97 and 10% vacuum at refrigerated (4°C) and room (23°C) temperatures. Probiotic solutions mixed with the different wall materials had different mass flow rates (kg/h) which produced as a result different evaporation rate values for the production of the probiotic powders. High maize starch and gum arabic were better protective agents than maltodextrin. L. plantarum encapsulated with high maize starch, packed under 97% vacuum, and stored at refrigerated temperature maintained the highest cell viability during 60 days of storage (0.14 log reduction).     

Studies on the Interaction of Arabic (Acacia senegal) and Mesquite (Prosopis juliflora) Cum as Emulsion Stabilizing Agents for Spray-Dried Encapsulated Orange Peel Oil

ABSTRACT

The encapsulation properties of pure mesquite and arabic gum powders and mixtures thereof with orange peel oil were measured. The highest rate of encapsulated oil was found to be 93.5 % for a ratio of 60.40% of arabic to mesquite gums. Pure arabic gum preparations were able to encapsulate similar amounts of the oil. Sensory evaluvation of the microencapsulates showed no significant differences (a≤.05) in flavor intensity beween orange peel oil encapsulated with pure arabic gum and mixtures containing mesquite gum.     

从阿拉伯胶水解液中结晶分离L-阿拉伯糖

阿拉伯胶水解液经结晶法提纯制备出粗L-阿拉伯糖.研究了时间、温度、pH值和溶剂对L-阿拉伯糖结晶率和纯度的影响,得到了由阿拉伯胶水解液中结晶分离L-阿拉伯糖适宜的工艺条件.该方法操作简便,生产效率高,易于工业化生产.     

Shear and extensional rheological investigations in solutions of grafted and ungrafted polysaccharides

Many polysaccharides with varying shear stability have been grafted with polyacrylamide branches to enhance their turbulent drag‐reducing and flocculating characteristics. Their aqueous solutions have been studied by shear and extensional rheometric techniques. All the solutions of grafted carboxymethyl cellulose, guar gum, starch, and sodium alginate exhibit shear‐thinning non‐Newtonian behavior. The viscosities are higher than those of ungrafted polysaccharides. The solutions of grafted carboxymethyl cellulose, guar gum and sodium alginate are spinnable. When subjected to uniaxial stretching in a stretching device, the formation of a thread and reduction of the thread diameter with time were observed. The stretching device was used to measure the relaxation time, which was found to be the largest (∼26 ms), on the order of flexible polyacrylamide, for the grafted carboxymethyl cellulose. Though a polyacrylamide solution degrades through nozzle flow and completely loses its extensional properties, a solution of grafted carboxymethyl cellulose retains about half its relaxation time because of the shear stability of polysaccharide chains and their structure. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 3200–3209, 2000     

Preparation,characterization and the effect of carboxymethylated chitosan–cellulose derivatives hydrogels on wound healing

Oxidized carboxymethyl cellulose (OCMC) was prepared by an oxidation reaction of carboxymethyl cellulose in the presence of sodium periodate. In situ crosslinked hydrogels were obtained through the crosslinking reaction between the active aldehyde of OCMC and the amino groups of the carboxymethyl chitosan (CMCS). The structure of the hydrogels was characterized by FTIR and scanning electron microscopy. Gelation time test showed that the hydrogel had the shortest gelation time of 24 s. The equilibrium fluid content, which represented the swelling degree, was evaluated and we found that the pH increased from 3.0 to 9.0, the equilibrium fluid content increased, and the highest equilibrium fluid content reached 312.83% as pH = 9.0. The wound healing efficacy of the hydrogel was evaluated in experimental deep second degree burns using a rat model. Results indicated that the wound covered with hydrogel was completely filled with new epithelium within 2 weeks, without any significant adverse reactions. The in situ crosslinked hydrogel fulfilled many critical elements in a wound dressing material. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Volatile Retention and Antifungal Properties of Spray-Dried Microparticles of Lippia sidoides Essential Oil

Spray drying microencapsulation of Lippia sidoides essential oil was investigated. Maltodextrin DE10 and gum arabic at different proportions (4:1, 3:2, 2:3, 0:1 m/m) was used as a carrier. The content of essential oil related to the carrier was 20 and 25% in weight and the emulsions were atomized from 30% up to 60% (m/m) of total solid concentration. Spray dryer inlet temperatures varied from 140 to 160°C and the best thermal efficiency and powder recovery were found at 160°C. Product properties and process performance were assessed on the basis of microscopic features of the powder (shape and size of microparticles), moisture content, and powder recovery. Encapsulation efficiency was estimated through determination of the content of essential oil in the microcapsules. The best encapsulation efficiency was related to experimental parameters as follows: solid content of the encapsulating composition of 50% (m/m), maltodextrin:gum arabic ratio of 0:1 (m/m) and carrier:essential oil ratio of 4:1 (m/m). Antifungal activities of microparticles were evaluated, evidencing their potential as important antifungal agents. The positive findings in this study encourage further research and provide perspectives for the development of phytotherapeutic products from essential oil of Lippia sidoides.     

Microencapsulation of Cinnamon Oleoresin by Spray Drying Using Different Wall Materials

Microencapsulation of spice oleoresin is a proven technology to provide protection against degradation of sensitive components present therein. The present work reports on the microencapsulation of cinnamon oleoresin by spray drying using binary and ternary blends of gum arabic, maltodextrin, and modified starch as wall materials. The microcapsules were evaluated for the content and stability of volatiles, entrapped and total cinnamaldehyde content for six weeks. A 4:1:1 blend of gum arabic:maltodextrin:modified starch offered a protection, better than gum arabic as seen from the t_1/2; i.e., time required for a constituent to reduce to 50% of its initial value.     

Microencapsulation of Cinnamon Oleoresin by Spray Drying Using Different Wall Materials

Microencapsulation of spice oleoresin is a proven technology to provide protection against degradation of sensitive components present therein. The present work reports on the microencapsulation of cinnamon oleoresin by spray drying using binary and ternary blends of gum arabic, maltodextrin, and modified starch as wall materials. The microcapsules were evaluated for the content and stability of volatiles, entrapped and total cinnamaldehyde content for six weeks. A 4:1:1 blend of gum arabic:maltodextrin:modified starch offered a protection, better than gum arabic as seen from the t_1/2; i.e., time required for a constituent to reduce to 50% of its initial value.     

Suppressive effect of alkyl ferulate on the oxidation of microencapsulated linoleic acid

The oxidation processes of linoleic acid mixed with ferulic acid or the 1‐pentyl, 1‐hexyl and 1‐heptyl ferulates, encapsulated with gum arabic or maltodextrin, were studied. The alkyl ferulates had a higher antioxidative effect than ferulic acid, but there was no significant difference among the three alkyl ferulates. Suppression of the oxidation by 1‐hexyl ferulate or ferulic acid was more effective at the higher molar ratios of the additive to linoleic acid. The processes were analyzed using the Weibull equation to evaluate the rate constant, k, and the shape constant, n. Although the k values for linoleic acid encapsulated with gum arabic were lower than that with maltodextrin, the suppressive effect of the alkyl ferulates was more remarkable for linoleic acid encapsulated with maltodextrin than with gum arabic because of the non‐antioxidative ability of maltodextrin. Because the partition coefficient of the alkyl ferulates was much greater than that of ferulic acid, most of the alkyl ferulates would be located in the linoleic acid phase of the microcapsules and effectively suppress the oxidation of linoleic acid.     

交联羧甲基化水葫芦纤维研制及其吸水与保水性能考察

以水葫芦纤维为原料,在乙醇、KOH碱性溶液中,以氯乙酸为醚化剂,制备了羧甲基化水葫芦纤维.并用FeCl3作交联剂,制得交联羧甲基化水葫芦纤维基吸水剂.通过FT-IR,SEM进行化学和表面结构表征、通过滴定法测定羧甲基纤维素的含量、通过称量法测定水葫芦基吸水剂在蒸馏水和典型的化肥液中的吸水率.考察了KOH、氯乙酸、交联剂用量以及反应温度对吸水率的影响,并进一步考察了水葫芦基吸水剂对土壤的保水性能.结果表明:水葫芦纤维、氯乙酸及KOH的适宜质量比为1∶1.25∶1.05;在60 ℃醚化2.0 h,接着在22℃用0.45 ％(wt)的FeCl3(相对羧甲基化水葫芦纤维)交联,所得交联羧甲基化水葫芦纤维基吸水剂在蒸馏水中的吸水率可达78 mL·g-1,在弱电解质(尿素)溶液中的吸水率略有下降、而在强电解质(氯化钾和碳酸铵)溶液中的吸水率明显下降;含5％交联羧甲基化水葫芦纤维基吸水剂的泥土,其保水率明显提高.