• Applied Chemistry for Engineering
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• 제28권2호
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• pp.186-192
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• 2017

In this study, water in oil (W/O) emulsion fuel was prepared with surfactant mixture of OIMS90 and NP12 by varying ratio of water to bunker-C oil, surfactant concentration and composition, emulsification time, stirring intensity, temperature and mixing time. Diesel engine performance and exhaust emissions were measured and analyzed with prepared emulsified fuel and compared with those measured using bunker Coil. The results indicated that bunker C emulsion fuel stabilized by surfactant mixture of OIMS90 and NP12 is efficient in reducing emissions of particulate matter, $NO_2$, CO, $CO_2$ and $SO_2$. The biggest reduction in exhaust emission was achieved by using emulsion fuel prepared by OIMS90/NP12 = 4 : 6, 500 ppm of total surfactant concentration and 10% water content at $80^{\circ}C$. Boiler efficiency test measured with emulsion fuel showed excellent energy efficiency compared with bunker C oil.

• Journal of the Society of Cosmetic Scientists of Korea
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• 제36권1호
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• pp.1-16
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• 2010

The preparation and properties of emulsions stabilized by the adsorption of solid particles at the oil-water interface are reviewed. Comparison is made with the behaviour of surfactant-stabilized emulsions. Many of the properties of Pickering emulsions are attributed to the large free energy of adsorption for particles. The main differences is due to the irreversible adsorption of particles to the interface. Phase inversion from w/o (water-in-oil) to o/w (oil-in-water) can be brought by increasing the volume fraction of water. Hydrophilic particles tend to form o/w emulsion whereas hydrophobic particles form w/o emulsion. The contact angle at the oil-water interface is main parameter to decide the emulsion type. The aspects of stability of Pickering emulsions are in contrast to general emulsions in some points. The possibility using Pickering emulsions for cosmetics is also proposed.

• Journal of Pharmaceutical Investigation
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• 제28권3호
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• pp.159-164
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• 1998

The O/W and W/O emulsions containing Scutellariae Radix extract(SRE) which is very slightly soluble in oil phases and sparingly soluble in water phases, were prepared by homogenizing water and oil phases with emulsifier. The diameters of emulsion were ranged from 100 to $300\;{\mu}m$. The viscosity of W/O emulsion was higher than that of O/W emulsion. W/O emulsion was more stable than O/W emulsion which was gradually degraded when tested by centrifuge method and temperature tolerance method at $50^{\circ}C$. The antibacterial activity of two emulsions was not significantly different from that of aqueous solution of SRE, and showed similar MIC and bacterial growth inhibition rate.

• Korean Journal of Food Science and Technology
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• 제31권4호
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• pp.1077-1083
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• 1999

This study was aimed to evaluate the effectiveness of hydrophilic, lipophilic antioxidants and emulsifiers by HLB (hydrophilic lipophilic balance) in different oil systems. Lipophilic antioxidant (${\delta}-tocopherol$), hydrophilic antioxidant (gallic acid) and emulsifier(lecithin, tween 20, span 60) were evaluated in relation to oil stability in bulk oil system (soybean oil) and emulsified with Tween 80 at $60^{\circ}C$. In the storage test ($60^{\circ}C$), gallic acid was more effective on the stability of oil oxidation than ${\delta}-tocopherol$ in bulk and emulsion system. Lecithin as a hydrophilic emulsifier was more effective than tween 20 on the stability of oil oxidation in bulk and emulsion system. Also span 60, a lipophilic emulsifier, was more effective than tween 20, a hydrophilic emulsifier, in bulk and emulsion systems.

• Journal of Microbiology and Biotechnology
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• 제15권1호
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• pp.29-34
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• 2005

W/O/W (water-in-oil-in-water) type multiple emulsion was applied to improve the storage stability of an antagonistic microorganism, Burkholderia gladioli. Encapsulation of microorganism into a W/O/W emulsion was conducted by using a two-step emulsification method. W/O/W emulsion was prepared by the incorporation of B. gladioli into rapeseed oil and the addition of polyglycerin polyriconolate (PGPR) and castor oil polyoxyethylene (COG 25) as the primary and secondary emulsifier, respectively. Microcrystalline cellulose was used as an emulsion stabilizer. To evaluate the usefulness of W/O/W emulsion formulation as a microbial pesticide for controlling the bacterial wilt pathogen (Ralstonia solanacearum), the storage stability and antagonistic activity of emulsion formulation were tested in vitro. The storage stability test revealed that the viability of formulated cells in emulsion was higher than that of unformulated cells in culture broth. At $4^{\circ}C$, the viabilities of formulated cells and unformulated cells at the end of 20 weeks decreased to about 2 and 5 log cycles, respectively. At $37^{\circ}C$, the viability of formulated cells decreased to only 2 log cycles at the end of storage. On the other hand, the viable cells in culture broth were not detected after 13 weeks. In activity test, formulated cells in emulsion were more effective in inhibiting the growth of pathogen than unformulated cells in culture broth. Unformulated cells completely lost their antagonistic activity during storage under similar conditions. The W/O/W multiple emulsion formulation was shown to be useful as the novel liquid formulation for biological control.

• Journal of the Korean Society of Food Science and Nutrition
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• 제45권4호
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• pp.533-541
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• 2016

Effect of polyphenols-rich cacao extract (CE) on lipid hydrolysis by pancreatic lipase was investigated by pH-stat digestion. Two types of substrate (oil vs. emulsion) prepared from soybean oil and CE were studied as types I and II. In the case of type I, addition of CE did not show retardation of lipid hydrolysis, showing that pancreatic lipase was not inhibited. Final digestibility rate (${\Phi}$ max, %) and initial rate (mM/s) of the 24-h aged control (52.31%, 0.03 mM/s) were similar to those of the CE-added sample (58.88%, 0.03 mM/s). However, in the case of typeII, the hydrolysis rates of the control and CE-added emulsion showed distinct differences as aging time increased to 43 days, showing lower digestion in the CE-added emulsion than the control. After 43 days, ${\Phi}$ max values of the control and CE-added emulsion were 92.13% and 77.68%, respectively.

• Journal of the Society of Cosmetic Scientists of Korea
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• 제25권1호
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• pp.137-155
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• 1999

The o/w emulsions were prepared by lysolecithin as a biosurfactantsto to emulsify oils with squalane(SQ), liquid paraffin(LP), octylpalmitate(OP), octylstearate(OS), alkyl benzoate(AB), isostearyl benzoate(ISB). The droplets size and shape of o/w emulsions were investigated by laser light scattering, With dynamic light scattering hydrodynamic radius(Rh) of emulsion droplets was varied from 150m to 250m and critical concentration of oil In which the hydrodynamic radius(Rh) of emulsion droplets decreased and increased was found in the point of 0.5wt% oil concentration, and it was found increasing the polarity of oil deccreased the droplets, the droplets size of SQ(polar oil) were lower than SQ(nonpolar oil) With static light scattering radius of gyration(R$_{g}$) of emulusion droplets was to be calculated. From measurements of the ratio of R$_{g}$R$_{h}$ it was found that the shape of droplet of ISB, AB(polar oils) were sphere, for OP, OS(apolar oil) were oblate, for LP, SQ(nonpolar oil) were rod. The viscosity of emulsion in the form of rod was higher than that of emulsion in the form of sphere.e.e.

• Food Science and Biotechnology
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• 제18권2호
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• pp.299-306
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• 2009

The purpose of this study was to prepare stable water-in-corn oil (W/O) emulsion droplets coated by polyglycerol polyricinoleate (PGPR). W/O emulsions (20 wt% aqueous phase, 80 wt% oil phase containing 8 wt% PGPR) were produced by high pressure homogenization (Emulsions 1), however, appreciable amount of relatively large water droplets (d>$10{\mu}m$) were found. To facilitate droplet disruption, viscosity of each phase was adjusted: (i) increased the viscosity of aqueous phase by adding 0.1 wt% xanthan (Emulsions 2); (ii) decreased the viscosity of oil phase and aqueous phase by heating them separately at $50^{\circ}C$ for 1 hr immediately before emulsification (Emulsions 3). Homogenizing at the elevated temperature clearly led to a smaller water droplet size, whereas xanthan neither improved nor adversely affected on the microstructures of the emulsions. In addition, the Emulsions 3 had good stability to droplet aggregation under shearing stress, thermal processing, and long term storage.

• Journal of the Korean Applied Science and Technology
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• 제36권1호
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• pp.226-236
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• 2019

In this study, functional and emulsifying properties of oil extracted by supercritical carbon dioxide from balloonflower(Platycodon grandiflorum A. DC) seeds were investigated. The oil was lower in total polyphenol content(8 mg/100 g), but higher in ${\alpha}$-tocopherol(14.15 mg/100 g), ${\beta}$-sitosterol(116 mg/100 g) and stigmasterol(8 mg/100 g) contents than seeds. Based on DPPH radical scavenging activity, the oil($IC_{50}=1235.5{\mu}g/mL$) showed similar antioxidant activity to the seeds($IC_{50}=1138.2{\mu}g/mL$). At 1%(w/w) lecithin, O/W emulsion with balloonflower seeds oil had turbidity, microscopic image, mean particle size and emulsion stability similar to emulsion with soybean oil, but had lower turbidity and emulsion stability and larger mean particle size than emulsion with perilla seeds oil. Its surface tension was similar to perilla oil emulsion.

• Clean Technology
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• 제15권1호
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• pp.54-59
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• 2009

In this study, the separation of water/bitumen emulsion was investigated by chemical demulsification method. Motor oils (GS Caltex Deluxe Gold V 7.5W/30, Hyundai gear oil 85W/140) and asphalt (AP-5, KS M 2201, Dongnam Petrochemical MFG. Co.) were used as model oils in the preliminary experiments to effectively remove water from water/bitumen emulsion. The bitumen extracted from Canadian oilsands was used in this study. The water/oil emulsion was not separated without demulsifiers, and Hyundai motor oil showed higher efficiency of water separation at a low concentration of demulsifier compared with that for GS Caltex motor oil. However, as the concentration increased, the efficiency did not rapidly increase compared with that of GS Caltex motor oil. It was highly speculated that the water phase of Hyundai motor oil was not dispersed well compared with that of GS Caltex motor oil because the viscosity of Hyundai motor oil was much higher than that of GS Caltex motor oil. The demulsifier of higher HLB (hydrophilic - lipophilic balance) value had high separation efficiencies in water/oil emulsion. The TWEEN 20 (polyoxyethylene sorbitan monolaurate solution) showed better separation efficiency than other demulsifiers.