• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.3 s.47
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• pp.353-359
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• 2004

The extent of silica flocculation can be modified by varying the silica concentration, aqueous phase pH, salt and polvmer concentration. High volume fraction W/O emulsion stabilized by hydrophobic silica was established with various aqueous phase conditions for cosmetic application. By increasing the silica concentration up to $1.0\;wt\%,$ the size of droplet decreased. A high silica concentration increased the viscosity of continuous oil phase by network formation, which resulted in target size of droplet. The stability of W/O emulsion is improved as increasing the aqueous phase pH. At low and intermediate pH, the emulsions became more stable by adding salt $(0.083\;mol\;dm^{-3}\;MgSO_4).$ At high PH, the presence of salt caused significant destabilization. The gelation behavior of the emulsion indicates that the effect of salt on silica-stabilized emulsion is derived from an electrostatic attraction. The addition of xanthan gum in aqueous phase increased the mono-dispersity of the W/O emulsion by making water more hydrophobic and hindering the recombination of droplets. In conclusion, these results indicate that very stable emulsifier-free, finely dispersed W/O emulsion can be achieved for cosmetic application by changing the aqueous phase composition.

• Food Science and Preservation
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• v.19 no.3
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• pp.337-343
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• 2012

The objective of this study was to characterize three different commercial (A, B and C) and two handmade (HM-AP, atmospheric pressure; HM-RP, reduced pressure) strawberry jams in relation to soluble solids, pH, total acid, total polyphenol, anthocyanin, color values, texture properties, and sensory evaluation. The soluble solid contents varied from 62.33 to 68.33 $^{\circ}Brix$, and the pH ranged from 3.59 to 3.70. The color L and a values were the highest in the HM-RP strawberry jam (p<0.05). The total polyphenol contents of commercial jams A, B, and C were 56.10, 97.59, and 105.85 mg GAE/100 g, respectively, and those of the HM-AP and HM-RP of handmade jams were 156.13 and 189.94 mg GAE/100 g. The anthocyanin contents of A, B, and C commercial jams were 1.51, 0.95, and 0.80 mg/100 g, respectively, and those of the HM-AP and HM-RP handmade jams were 2.64 and 9.16 mg/100 g. The phenolic contents of the HM-RP jam were significantly much higher than those of the other jams. The hardness ranged from $5.67{\times}10^3$ (HM-AP jam) to $41.91{\times}10^3$ (jam B) dyne/$cm^2$, the jelly strength ranged from 40.08 (HM-AP jam) to 180.33 (jam B) dyne, and the strength ranged from 83.84 (jam C) to 302.93 (jam B) g. The sensory evaluation of the color, flavor, sweetness, sourness, viscosity and overall acceptability of the HM-RP jam showed higher values than those of the other jams. Especially, the highest value of the color score was found in the HM-RP jam. The electon donating abilities of jams A, B, and C and of the HM-AP and HM-RP jams were 44.27, 41.70, 53.06, 69.08, and 73.21%, respectively. These results indicated that the HM-RP strawberry jam prepared with reduced pressure using micro-oxygen technology was a good source of phenolic compounds, total polyphenols and anthocyanin, and had a high level of antioxidant activity.

• Food Science and Preservation
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• v.16 no.1
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• pp.60-67
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• 2009

The purpose of this research was to develop the apple dressing sauce added pine mushroom (Tricholoma matsutake Sing.) and chitosan which has excellent functionality and scent. An apple dressing sauce with pine added to it was manufactured and tested for sensuality and also for quality changes during storage. The sensory test of the sauces added pine mushroom, the apple dressing sauce added pine mushroom and the apple dressing added pine mushroom and chitosan scored high points. The chromaticity of the apple dressing sauce with pine mushroom compared to the pine didn't show much difference in the L, a, b values and also in the sauces added pine and chitosan, the apple dressing showed less change. At $4^{\circ}C$ and 25, the viscosity of the sauces with pine mushroom showed a small increase in all samples as the storage duration went on. At $4^{\circ}C$, a continuous decrease of the pH was seen in all of the apple dressing sauce added with pine mushroom on storages and from 30 days the pH seemed to start increasing slightly. During storage, the titratable acidity in all samples of the apple dressing with pine mushroom at $4^{\circ}C$ and $25^{\cird}C$ seemed to some what increase as the term went on but there was no significant differences to the acidity. At $4^{\circ}C$, the total viable cells in the apple dressing with pine mushroom showed $1.7{\times}10^{2}CFU/g$ which was the lowest in the beginning of storage period but as the storage period grew longer the total viable cells increased in all of the samples.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.3
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• pp.311-321
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• 2008

In order to improve the insufficient protein content of Jeung-Pyun with respect to sitology, as well as its fermentation process, this study prepared Jeung-Pyun doughs containing 0, 5, 10, 15, and 20 g of milk, respectively, and examined their mechanical and functional characteristics. The internal structure of the Jeung-Pyun was observed by SEM. With regard to color, the L-value increased with increasing amounts of added milk, and the highest value (65.43) occurred in the group containing 20 g of added milk; however, there were no significant differences among groups. The group containing 20 g of added milk also presented the highest a-value, and the samples with added milk had higher b-values than the control. At 8 hours of fermentation, the 10 g- and 15 g-added milk groups had viscosities of 5726.67 and 6600 respectively; viscosity increased with increasing amounts of milk, and the added-milk groups had significantly higher values than the control group. Hardness also increased with increasing amounts of added milk. However, there were no significant differences in resilience and cohesive power among the groups. The groups containing 5 and 10 g of added milk had the lowest cohesion and break values. For appearance, the group without added milk had the whitest color. Pore size decreased and showed less uniformity as the amount of added milk increased. The unique tackju aroma of Jeung-Pyun decreased significantly as the level of added milk increased, and the 20 g addition presented the lowest value. The 10 g-added milk group had the highest level of sweetness, and sourness increased with increasing amounts of added milk. For softness, the control group was estimated as slightly softer than the added-milk groups. The stickiest sample was generally preferred when considering taste, white color, and sweetness. Among the quality characteristics, having greater stickiness, resilience, moisture, and softness was better in terms of chewing. Overall, the size of the Jeung-Pyun containing 10 g of milk was even and well-developed.

• Korean Journal of Agricultural Science
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• v.10 no.1
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• pp.135-145
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• 1983

This study was conducted to obtain the fundamental data for the processing of carrot juices and know the effects of blanching conditions, acid and alkali treatments and sterilization on the quality factors of carrot juices. The result obtained was as follows. 1. Blanching condition, $100^{\circ}C$, 5min. was the most effective for the Brix, amino-N content, suspended solid, light transmittance and yield of carrot juices among $90^{\circ}C$, 15min., $95^{\circ}C$, 10 min., and $100^{\circ}C$, 5min. 2. 0.05N-acetic acid solution was the most effective blanching solution for the suspended solid, light transmittance, viscosity and yield of the juices compared to 0.05N-citric acid and 0.03N-hydrochloric acid solution. 3. The color changes during the processing of carrot juices caused by blanching process rather than sterilization process. 4. The ${\beta}$-carotene in carrot juices was very stable and about 80 % of it was remained in the carrot juice which had been blanched, extracted and sterilized at $115^{\circ}C$ for 30min. 5. Alkali treatment for the juice from acid - blanched carrots formed discoloration after sterilization. 6. Relative content (%) of sugars in raw carrot juice we re ribose, 8.51%; fructose. 10.15%; glucose, 12.25%; sucrose, 49.53% and oligosaccharide, 19.56%. When the carrots were blanched in boiling water, the contents of monosaccharide and disaccharide decreased slightly but that of oligosaccharide increased slightly, however, when the carrots were blanched in acid solution, and then neutralized and sterilized, relative contents of ribose and sucrose decreased remarkably but that of oligosaccharide increased considerably and those of glucose and fructose increased slightly. 7. Nineteen sorts of free amino acid were detected from the carrot juices and the mains of them were threonine+asparagine, alanine, serine+glutamine, aspartic acid, arginine, and glutamic acid.

• Korean Journal of Agricultural Science
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• v.22 no.1
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• pp.1-10
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• 1995

All agricultural crops and products should be cultured, harvested, handled and processed by the proper mechanical methods in the mechanized farming systems. Agricultural crops might be injured or deformed through various working stages due to static or dynamic forces of machines. Mechanical forces had to be applied with proper degrees to the agricultural crops in incoincidence with properties of crops without any damage of crops so as to increase the work efficiency qualitatively. Knowledges of mechanical properties of agricultural materials are essential to prevent of agricultural crops in relation with mechanical farming system. This study was carried out to examine and analyze the creep behavior of the rice stalk on growing and harvesting periods by mechanical model with computer measurement system in radial directional compressive force and bending force. The creep behavior of the rice stalk could be predicted precisely and its results approached closely to the measured values. The creep behaviors were increased greatly with increase of compressive force, namely, the steady state creep behavior occurred at the force less then 25N and the logarithmic creep behavior at the force bigger than 30N. The instantaneous elastic modulus $E_o$ and the retardation time ${\tau}_K$ were increased together with increase of applied forces, meanwhile the retarded elastic modulus $E_r$ and viscosity ${\eta}_v$ were decreased with increase of applied forces in mechanical model being expected the creep behavior in relation with the level of applied forces, which was well explained that the rice stalk might be visvo-elastic material. In the creep test along the stalk portion with compressive force and bending force, the intermediate portion showed greatest values and also the lower portion showed the least values, which implied that the intermediate portions of rice stalk were very weak. The steady state creep behavior occured at the intermediate portion and the upper portion in the rice stalk at the compressive force larger than 25.0N, which showed the possibility of injury due to external forces.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.6
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• pp.521-537
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• 2012

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2011. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends of thermal and fluid engineering have been surveyed as groups of fluid machinery and fluid flow, thermodynamic cycle, and new and renewable energy. Various topics were presented in the field of fluid machinery and fluid flow. Research issues mainly focused on the rankine cycle in the field of thermodynamic cycle. In the new and renewable energy area, researches were presented on geothermal energy, fuel cell, biogas, reformer, solar water heating system, and metane hydration. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer, nanofluids and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer above liquid helium surface in a cryostat, methane hydrate formation, heat and mass transfer in a liquid desiccant dehumidifier, thermoelectric air-cooling system, heat transfer in multiple slot impinging jet, and heat transfer enhancement by protrusion-in-dimples. In the area of pool boiling and condensing heat transfer, researches on pool boiling of water in low-fin and turbo-B surfaces, pool boiling of R245a, convective boiling two-phase flow in trapezoidal microchannels, condensing of FC-72 on pin-finned surfaces, and natural circulation vertical evaporator were actively performed. In the area of nanofluids, thermal characteristics of heat pipes using water-based MWCNT nanofluids and the thermal conductivity and viscosity were measured. In the area of industrial heat exchangers, researches on fin-tube heat exchangers for waste gas heat recovery and Chevron type plate heat exchanger were implemented. (3) Refrigeration systems with alternative refrigerants such as $CO_2$, hydrocarbons, and mixed refrigerants were studied. Heating performance improvement of heat pump systems were tried applying supplementary components such as a refrigerant heater or a solar collector. The effects of frost growth were studied on the operation characteristic of refrigeration systems and the energy performance of various defrost methods were evaluated. The current situation of the domestic cold storage facilities was analyzed and the future demand was predicted. (4) In building mechanical system fields, a variety of studies were conducted to achieve effective consumption of heat and maximize efficiency of heat in buildings. Various researches were performed to maximize performance of mechanical devices and optimize the operation of HVAC systems. (5) In the fields of architectural environment and energy, diverse purposes of studies were conducted such as indoor environment, building energy, and renewable energy. In particular, renewable energy and building energy-related researches have mainly been studied as reflecting the global interests. In addition, various researches have been performed for reducing cooling load in a building using spot exhaust air, natural ventilation and energy efficiency systems.

• Journal of the Korean Vacuum Society
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• v.18 no.1
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• pp.66-72
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• 2009

The detection methods are required to monitor and diagnose the abnormality on the insulation condition inside a gas-insulated switchgear (GIS). Due to a good sensitivity to the products decomposed by partial discharges (PDs) in $SF_6$ gas, the development of a SWNT gas sensor is actively in progress. However, a few numerical studies on the diffusion mechanism of the $SF_6$ decomposition products by PD have been reported. In this study, we modeled $SF_6$ decomposition process in a chamber by calculating temperature, pressure and concentration of the decomposition products by using a commercial CFD program in conjunction with experimental data. It was assumed that the mass production rate and the generation temperature of the decomposition products were $5.04{\times}10^{-10}$ [g/s] and over 773 K respectively. To calculate the concentration equation, the Schmidt number was specified to get the diffusion coefficient functioned by viscosity and density of $SF_6$ gas instead rather than setting it directly. The results showed that the drive potential is governed mainly by the gradient of the decomposition concentration. A lower concentration of the decomposition products was observed as the sensors were placed more away from the discharge region. Also, the concentration increased by increasing the discharge time. By installing multiple sensors the location of PD is expected to be identified by monitoring the response time of the sensors, and the information should be very useful for the diagnosis and maintenance of GIS.

• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.768-775
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• 2005

Lentinus edodes powder was added at 1-3%(w/w) to improve functional properties of jocheong. Content of crude protein, ash, crude lipids, total mineral, free sugar and reducing sugar increased with increasing amount of L. edodes powder, while viscosity and solid and carbohydrate contents decreased. Through amino acid analysis, 17 amino acids were identified and quantified, glutamic acid being the major amino acid. No significant differences were observed in fatty acid composition and pH between control and L. edodes powder-added jocheong. Addition of mushroom powder in jocheong decreased lightness, yellowness and redness in Hunter's color value. Sensor score of jucheong containing 1% of L. edodes powder was similar to that of control. Results showed jocheong containing less than 2% L. edodes powder gave highest scores in quality characteristics and sensory evaluation.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.268-275
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• 2004

Effects of soaking time and particle size on physicochemical properties of nonwaxy rice flour were investigated. Nonwaxy rice grains were soaked at $4^{\circ}C$ for 0, 1, 12, and 24 hr, dried at room temperature, and milled, Resulting flours were passed through 45-mesh ($<355{\mu}m,\;IL45$) and 100-mesh ($<150{\mu}m\;IL100$) sieves and separated into $<40{\mu}m\;and\;40-100{\mu}m$ series. IL45 series showed higher amount of large particles ($40-100{\mu}m$) than IL100 series. As the soaking time increased, protein and ash contents decreased, and amylose content, water-binding capacity, swelling power, and solubity of nonwaxy rice flours increased. Swelling power and solibility of nonwaxy rice flours also increased between $65-85^{\circ}C$. Water-binding capacity, swelling power, and solubility of IL100 series were higher than those of IL45 series. 12 hr-soaked nonwaxy rice flour pastes showed higher peak viscosity and breakdown but lower setback and visicosity at $95\;and\;50^{\circ}C$ than 1 hr-soaked ones. X-Ray diffractograms of nonwaxy rice flours were not affected, whereas surface appearance was affected, by soaking time and particle size.