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.     

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.     

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.     

Efficacy of Microencapsulated Carvacrol in Oxidative Stability of Sunflower Oil

The objective of this study is to improve the oxidative stability of sunflower oil using encapsulated carvacrol during 25 times repeated frying experiments. Microencapsulated carvacrol powders are produced by spray drying using binary and ternary blends of gum arabic (GA), maltodextrin (MD), and corn starch as encapsulating agents. In most cases, the encapsulation efficiency decreases as the amount of GA decreases in the wall mixture. Microencapsulated carvacrol powders prepared with GA (100%), GA + MD (75:25), and GA + MD + starch (67.5: 22.5: 10), which are found to have higher encapsulation efficiency values, are used as antioxidants in dough frying experiments. Frying experiments are performed with the addition of encapsulated and/or unencapsulated forms of carvacrol into the sunflower oil or dough. Encapsulated carvacrol is found to be more effective than unencapsulated carvacrol and butylated hydroxyanisole (BHA) in repeated frying experiments. The addition of carvacrol into oil provides better protection compared to addition into dough. Protective effects of encapsulated and unencapsulated forms of carvacrol in frying trials are successfully discriminated by applying principal component analysis. Practical Application: Carvacrol and thymol are the major constituents of thyme (Thymus vulgaris L.) essential oil. These compounds are responsible for the main bioactive properties of thyme oil. Therefore, in this study, pure commercial carvacrol was encapsulated and tested for its protective effect in sunflower oil during repeated dough frying. The effectiveness of the carvacrol in encapsulated form may be a consequence of the prevention of volatilization. The results of this study are remarkable for food applications requiring high temperatures.     

Effect of Homogenization Pressure and Oil Load on the Emulsion Properties and the Oil Retention of Microencapsulated Basil Essential Oil (Ocimum basilicum L.)

The objective of this work was to evaluate the influence of oil concentration and homogenization pressure on the emulsion and particle properties during the microencapsulation of basil essential oil by spray drying, using gum arabic as the wall material. Experiments were planned according a 2² rotational central composite design. The independent variables were oil concentration with respect to total solids (10–25%) and homogenization pressure (0–100 MPa). Emulsions were analyzed for droplet mean diameter, stability, and viscosity, and particles were analyzed for oil retention, moisture content, particle size, and morphology. Emulsion viscosity was not affected by any of the independent variables. The increase in the homogenization pressure from 0 to 100 MPa resulted in smaller emulsion droplet size (down to 0.40 µm) and, consequently, higher oil retention (up to 95%). On the other hand, higher oil loads (25%) resulted in poorer oil retention (51.22%). Microencapsulation of basil essential oil using gum arabic as the wall material proved to be a suitable process to obtain powdered basil essential oil, presenting great oil retention with the use of lower oil concentration and higher homogenization pressure.     

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).     

Microencapsulation of Kaffir Lime Oil and Its Functional Properties

This paper describes the effects of spray drying temperature and wall materials on functional properties of kaffir lime oil microcapsules. The effects of spray drying were studied at inlet air temperatures at 160, 180, and 200°C. Two coating materials (konjac glucomannan and gum arabic) were employed in this study. The results indicate that kaffir lime oil had antibacterial activity against all tested pathogens and was able to inhibit Vibrio cholerae comparable to a standard antibiotic. The combination of konjac glucomannan and gum arabic (KGM+GA) can enhance the yield and retention of total oil in the microcapsules more than using konjac glucomannan alone as a wall material. Increasing inlet air temperature resulted in a decrease of antibacterial activity and amount of bioactive volatile compounds. Physical and chemical properties of the microcapsules did not differ significantly (p > 0.05) in terms of process yield, a _w , moisture content, efficiency in retention of total, surface and inner oil, water solubility index, and color except at inlet air temperature of 200°C. However, it was found that the kaffir lime oil microcapsules from KGM+GA produced at inlet temperature of 180°C had the best functional properties in terms of antibacterial activity and efficiency of retention of total encapsulated oil.     

Screening of different hydrocolloids for improving the quality of fried papad

Papads prepared from cereals, legumes and combinations thereof are India s contribution to the international menu. They are specially relished as snacks in fried form. In the present study hydrocolloids amounting to 0.25‐1.00% of fried papads prepared from black gram were investigated. The hydrocolloids chosen were guar gum, carrageenan, carboxymethyl cellulose, hydroxypropylmethyl cellulose, gum tragacanth, gum karaya, gum ghatti and gum arabic. It was observed that carboxymethyl cellulose was the most effective in increasing the diametrical expansion of the papads at a concentration of 1.00%, while gum arabic at 1.00% caused a maximum reduction in oil content (26.19% as compared to control). Gum tragacanth at 0.5% gave the best texture, measured as crispness using Steven's LFRA texturimeter.     

Physicochemical Properties of Encapsulated Red Raspberry (Rubus idaeus) Powder: Influence of High-Pressure Homogenization

Encapsulated red raspberry (Rubus idaeus) powders with gum arabic were produced using a spray-drying method. The raspberry puree samples were treated with and without high-pressure homogenizers prior to spray drying. The physicochemical properties of spray-dried raspberry powders were analyzed. The median particle size (X ₅₀) of raspberry powder produced with high-pressure homogenized puree (14.6 µm) was smaller than raspberry powder produced without high-pressure homogenization applied to puree (18.3 µm). Glass transition temperatures and water contents of encapsulated raspberry powders were not significantly different (p > 0.05) at equivalent water activities. High-pressure homogenization of puree resulted in greater apparent density and porosity for encapsulated raspberry powder. Greater particle size resulted in higher hygroscopicity and water solubility index (WSI) for encapsulated raspberry powder produced without high-pressure homogenization of puree. Anthocyanins concentration was greater in raspberry powder pretreated with high-pressure homogenization although powder exhibited lower brightness, redness, and yellowness.     

Hydrolytic Activity of Castor Bean Powder: Effect of Gum Arabic,Lipase and Oil Concentrations

Lipase activity from castor bean seed powders was evaluated in hydrolysis reactions at 37 °C. The effects of different concentrations of lipase powder (LP), substrate (high oleic sunflower oil, O) and surfactant (gum arabic, A) on lipase activity (R) were assessed using experimental designs. Considered variable bounds were: 0.05–0.15 g_LP, 0.07–0.20 oil:aqueous phase (w/w) and 0–0.025 g gum arabic/mL. All variables had significant effects on the transformed response, R ^1/2. The most important result was the negative effect of gum arabic in lipase activity, even when high oil concentrations were used. Experimental lipase activities involved in this work were within 0.32–16.90 mmol_FFA/g_oil·g_LP·h. Using 0.05 g_LP and 0.20 oil:aqueous phase (w/w) without gum arabic, the activity of 20.47 ± 7.19 mmol_FFA/g_oil·g_LP·h was reached.     

Microencapsulation of Rosemary Essential Oil: Characterization of Particles

This study evaluated the influence of wall material concentration (10–30%), inlet temperature (135–195°C), and feed rate (0.5–1.0 L · h^?1) on the properties of rosemary oil microencapsulated by spray-drying, with gum arabic as carrier. Powder recovery, surface oil, oil retention, and hygroscopicity varied from 17.25%–33.96%, 0.03%–0.15%, 7.15%–47.57%, and 15.87%–18.90%, respectively. The optimized conditions were determined to be a wall material concentration of 19.3%, an inlet air temperature of 171°C, and a feed flow rate of 0.92 L · h^?1. At this condition, particles presented no fissures and the compositions of pure and microencapsulated oil were similar. The sorption isotherms could be described by the GAB model.     

Microencapsulation of Essential Oil from Fruits of Pterodon emarginatus Using Gum Arabic and Maltodextrin as Wall Materials: Composition and Stability

The present investigation reports the microencapsulation of the essential oil from the fruits of Pterodon emarginatus by spray drying using gum arabic and maltodextrin. X-ray diffraction studies established that the essential oil was entrapped within the microcapsules rather than being adsorbed onto the surface. The morphology of the microcapsules was analyzed by scanning electron microscopy (SEM). The particle size (Sauter [3,2]) and particle size distribution of microcapsules were also determined. The microcapsules were evaluated for the content and stability of both volatiles and the major component, β-caryophyllene, for 45 days. A 1:3:3.6 blend of essential oil: gum arabic: maltodextrin offered the best protection, with 98.63% of the essential oil being retained and the same proportion of β-caryophyllene being entrapped. The obtained results showed that the microcapsules might have potential applications in the protection of essential oil from fruits of P. emarginatus and contribute to the development of an herbal medicine.     

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.     

Studies of Terminalia bellerica (Bahera), a natural gum,as an additive in a water-based adhesive composition

Terminalia bellerica (Bahera), a natural gum, was used as an additive in water-based natural rubber adhesive formulations. The lap shear strength of joints with wood substrates increased with the increase of natural gum concentration up to 80 phr (parts per hundred parts of rubber) loading. Similarly, the peel strength of the canvas to canvas joints increased with the incorporation of the gum. The results were explained with the help of viscoelastic properties, morphology and surface chemistry of the rubber–gum mixtures.     

Protective Effect of Encapsulation in Fermentation of Limonene-contained Media and Orange Peel Hydrolyzate

This work deals with the application of encapsulation technology to eliminate inhibition by D-limonene in fermentation of orange wastes to ethanol. Orange peel was enzymatically hydrolyzed with cellulase and pectinase. However, fermentation of the released sugars in this hydrolyzate by freely suspended S. cerevisiae failed due to inhibition by limonene. On the other hand, encapsulation of S. cerevisiae in alginate membranes was a powerful tool to overcome the negative effects of limonene. The encapsulated cells were able to ferment the orange peel hydrolyzate in 7 h, and produce ethanol with a yield of 0.44 g/g fermentable sugars. Cultivation of the encapsulated yeast in defined medium was successful, even in the presence of 1.5% (v/v) limonene. The capsules’ membranes were selectively permeable to the sugars and the other nutrients, but not limonene. While 1% (v/v) limonene was present in the culture, its concentration inside the capsules was not more than 0.054% (v/v).     

Optimization of Freeze Drying Conditions for Purified Pectinase from Mango (Mangifera indica cv. Chokanan) Peel

Response surface methodology (RSM) along with central composite design (CCD) was applied to optimize the freeze drying conditions for purified pectinase from mango (Mangifera indica cv. Chokanan) peel. The effect of pectinase content (-2.66, 62.66 mg/mL), Arabic gum (-1.21, 10.21%, w/v), and maltodextrin (0.73, 7.26%, w/v) as independent variables on activity, yield, and storage stability of freeze-dried enzyme was evaluated. Storage stability of pectinase was investigated after one week at 4 °C and yield percentage of the enzyme after encapsulation was also determined. The independent variables had the most significant (p < 0.05) effect on pectinase activity and yield of the enzyme. It was observed that the interaction effect of Arabic gum and maltodextrin improved the enzymatic properties of freeze-dried pectinase. The optimal conditions for freeze-dried pectinase from mango peel were obtained using 30 mg/mL of pectinase content, 4.5 (%, w/v) of Arabic gum, and 4 (%, w/v) of maltodextrin. Under these conditions, the maximum activity (11.12 U/mL), yield (86.4%) and storage stability (84.2%) of encapsulated pectinase were achieved.     

Stabilization of Lipoxygenase-1 from Glycine max by Microencapsulation

Lipoxygenase from soybean was encapsulated and the effect of different carrier materials (whey protein, gum arabic, whey protein along with sodium alginate and maltodextrin) on enzyme stability during spray drying was studied and compared with freeze drying. The addition of polyethylene glycol (PEG-4000) during spray drying evidently enhanced enzyme stability. Total activity of lipoxygenase after spray drying was 1.14 × 10⁴(whey protein isolate), 1.2 × 10⁴(gum arabic), 1.09 × 10⁴ (whey protein isolate + sodium alginate), 1.44 × 10⁴(maltodextrin), and 1.55 × 10⁴(PEG + maltodextrin). Highest enzyme activity recovery of 72.02% was achieved with the combined addition of maltodextrin and PEG-4000. Moisture, scanning electron microscopy analysis, and storage studies were carried out for spray- and freeze-dried enzyme.     

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.     

超临界CO2萃取柑橘精油的工艺研究

以柑橘皮为实验材料,以柑橘精油萃取率为指标,用超临界二氧化碳萃取方法,在萃取温度、萃取压力、萃取时间、投料量试验的基础上,经正交试验对柑橘皮中精油的萃取工艺条件进行了优化。研究发现柑橘皮中精油超临界二氧化碳萃取的最佳萃取工艺条件为压力30 MPa,温度32℃,投料量120 g,萃取时间2.5 h,柑橘精油的萃取率为3.60%。     

Volatiles Retention in the Drying of Skin Forming Materials PART 3: Heat-Sensitive Materials

ABSTRACT

Ethanol retention in solutions was determined by drying single droplets in a horizontal wind tunnel, with gelatine (Bloom numbers 60 and 150) and gum arabic as encapaulants. The variation in ethanol content, droplet temperature history and crust structure were evaluated in each case. General conclusions are provided for parameters determining volatile- retention in convective drying.