본 연구에서는 일반적으로 O/W 에멀젼에 비해 안정화가 어려운 W/O 에멀젼, 특히 유동성이 높은 저점도 W/O 에멀젼의 안정성 증진을 위하여 유화제, 전해질, 유화 안정화제, 겔화제 등을 적용한 다양한 실험을 수행하여 보았다. 그 결과 이번 실험에서는 Polyglyceryl-4 diisostearate/ polyhydroxystearate/sebacate를 주 유화제로 하면서 PEG-30 dipolyhydroxystearate와 Cetyl PEG/PPG-10/1 dimethicone을 보조 유화제로 하는 유화 체계에, 전해질로 Sodium chloride를 0.5 %, 유화 안정화제로 Distearyldimonium chloride를 1 %, 유상 겔화제로 Glyceryl behenate/eicosadioate를 0.5 % 적용한 유화 입자도 작고 조밀하며 점도도 2,000 cps 이하로 일정하게 유지되는 안정한 저점도 W/O 에멀젼을 제조할 수가 있었다. 또한 상기와 같은 에멀젼 베이스에 무기 자외선 차단성분의 적용 실험을 통하여 안정성이 우수한 저점도 플루이드형 자외선 차단제품의 개발 가능성도 긍정적으로 검토 할 수가 있었다.

In case of performing asphalt pavement overlay on existing concrete pavement layer, applying asphalt emulsion tack-coating or spreading prime-coating is considered to improve adhesion between asphalt and concrete layer. After coating work is done a curing process is considered not only for promoting evaporation process in coated (and/or spread) asphalt emulsion, but also for generating a membrane which can act as a bonding agent. Finally, asphalt overlay construction is performed when this curing process is completely done. However, during asphalt overlay construction process remarkable amount of spread tack-coating layer is lost due to asphalt material transfer vehicles (e.g. trucks, approximately 40~50% of total spread tack coating material is lost). In this paper, a new pavement equipment contains simultaneous asphalt emulsion spreading ability and corresponding construction techniques are introduced. Through applying this equipment, non-stop two step sequent working process: spreading asphalt emulsion on to existing concrete pavement layer then paving asphalt material for overlay construction, is available. During pavement working process temperature of asphalt material was kept with ranged between 130ºC and 170ºC. After performing field performance evaluation, it was found that crucial improvement in pavement layer adhesion, crack and rutting resistant ability were observed compared to the conventional paving method.

Microcapsule membranes are fabricated with PLGA through double emulsion method and solvent evaporation method. In outer aqueous phase, surfactants such as PVA were replaced with metal salts as CaCl2 and MgCl2. Inside the microcapsule membrane, BSA was encapsulated as the model drug. Morphologies, BAS encapsulation efficiencies and BAS releasing behaviors are investigated. Through the process, microcapsule membranes with diameters of μm are generated and, through this work, we got a conclusion that the metal salts could be a good choice to replace PVA to solidify the microcapsule membrane surfaces.

This study was performed to analyze a saltiness enhancement at the same salt content through multiple emulsion. We compared the samples with different conditions to determine the optimum stability conditions of water-in-oil through layer separation rate, microscopic observation and size analysis. Four electrolytes such as NaCl, KCl, MgCl2, and CaCl2 were used and agar contents ranged from 0 to 1% were experimented at different volume ratios including 5:5, 4:6, 3:7, 2:8, and 1:9 of water and oil. As a result of this study, the droplet size according to the electrolyte type did not show significant differences (p<0.05). Therefore, KCl was used to facilitate in-body excretion of NaCl in the outer water phase, and corn oil containing 8%(w/w) polyglycerol polyricinoleate was used as oil phase. When the volume ratio of water and oil was 3:7, 2:8, and 1:9, the layer separation rate was relatively slow and droplet size was also small. It reveals that the particle size becomes smaller as the water volume ratio decreases. However, considering the amount of water to be stored and eluted on the inner water, appropriate volume ratio of water and oil should be adopted to 3: 7. At Microscopic observation depending on agar concentrations, small particle size appeared at 0.2% and 0.4% agars. When the water and oil ratio was fixed at 3:7, the particle size was measured at 0.2% and 0.4% agar using a zeta sizer. In conclusion, the droplet size of 0.2% agar was smaller than 0.4%. Therefore, the most stable water-in-oil emulsion was obtained with 0.2% agar, when water to oil ratio was 3:7.

Vitamin A, particularly all-trans retinol is excellent for anti-aging but is sensitive to oxygen, heat and light and has low solubility in water. In this study, retinol was encapsulated within oil-in-water (O/W) emulsion, protein-based particle and cycloamylose(CA). And then, it confirms that retinol contained in each delivery system is stable to UV, pH, and temperature and finally measures bioaccessibility. O/W emulsion was compared according to the type and concentration of emulsifier. UV stability of retinol increased with increasing oil concentration. More than 10 wt% of oil was required to maintain stable retinol (50% residual after 24 hours of irradiation). Using anionic emulsifier, retinol had unstable storage stability regardless of oil concentration and temperature. Protein based particle was compared according to the type of stabilizer and polysaccharide. UV stability of retinol was highest in pectin-coated particles. However, 20% retinol remains after 6 hours of irradiation and is vulnerable to UV compared to other delivery systems. In pH stability, pectin-coated particles also stably retained retinol. Inclusion complex of retinol and CA was compared according to the concentration of CA. When CA was used, the residual amount of retinol to UV was high (50% residual after 24 hours of irradiation) regardless of the concentration of the host molecule. In the case of storage stability, retinol remained significantly higher regardless of temperature when cycloamylose was used. It was finally confirmed bioaccessibility each of retinol delivery system. O/W emulsion was determined by emulsifier type, protein-based particle by coating agent, and inclusion complex by CA concentration. All O / W emulsions retained more than 50% retinol, protein based particles retained more than 80% retinol, and inclusion complex retained more than 70% retinol. The bioaccessibility of pure retinol is about 20%. This study provides important information for designing effective delivery systems for improving the stability of retinol.

Different strategies are studied to incorporate lipid-soluble bioactive molecules into water-based food systems. However, these systems solely cannot protect the core compound through the storage period, especially when the core is exposed to environmental stress factors. Water soluble fraction of the crude extract from Enteromorpha prolifera was analyzed for its physicochemical characteristics including chemical composition, structure, rheological and thermal properties. The extract was added to O/W emulsion system containing retinol and stabilized with Tween 20, WPI and sodium caseinate to improve storage stability through different modes of action; as a chelator of metal ions and as a scavenger of radicals. Storage stability was mainly determined by zeta potential, particle size distribution, and retinol retention. The water-soluble extract of E.prolifera mainly consisted of anionic polysaccharide, while impurities of protein, mineral and other pigments were present. Mode of action analysis showed that the extracts had both ferrous ion chelating ability(EC50=0.67%) and free radical scavenging ability(EC50=0.23%), indicating a multifunctioning mechanism of the heterogeneous extract. Addition of extract (0.1%~1% in total emulsion) did not affect the physical stability during 1 week storage. Protective materials are often added to food systems to improve the stability of core materials but excessive use of additives may be repulsive to consumers. In contrast, the optimum concentration range of E.prolifera extract is much lower compared to that of conventional usage of other materials and has lower toxicity to that of strong chelators while providing effective protection.

PURPOSES: The purpose of this study was to develop an urgent road-repair system and perform a field applicability test, as well as discover the optimum mix design for machine applications compared to the optimum mix design for lab applications. METHODS: According to reviews of the patent and developed equipment, self-propelled and mix-in-place equipment types are suitable for urgent pavement repair, e.g., potholes and cracks. The machine-application mix design was revised based on the optimum lab-test mix design, and the field application of a spray-injection system was performed on the job site. The mixture from the machine application and lab application was subjected to a wet-track abrasion test and a wheel-tracking test to calibrate the machine application. RESULTS and CONCLUSIONS : This study showed that the binder content could differ for the lab application and the machine application in the same setting. Based on the wet-track abrasion test result, the binder contents of the machine application exceeded the binder contents of the lab application by 1-1.5% on the same setting value. Moreover, the maximum dynamic stability value for the machine application showed 1% lower binder contents than the maximum lab-application value. Collectively, the results of the two different tests showed that the different sizes and operating methods of the machine and lab applications could affect the mix designs. Further studies will be performed to verify the bonding strength and monitor the field application.

Curcumin is an active polyphenolic compound with antioxidant, anti-inflammatory and antitumor properties. Curcumin, however, is highly unstable under physiological conditions due to its low stability in acidic and alkaline conditions. Therefore, the objective of this study was to investigate the effects of enzyme-treated rice starch as a wall material on the stability of curcumin in oil-in-water emulsion under different pH conditions. The rice starch was treated using 4-a-glucanotransferase for different time periods and their molecular weight distribution was measured by HPSEC. Curcumin was encapsulated within lipid droplets of O/W emulsion prepared with Tween 20 and the modified rice starch in the aqueous phase at different concentrations (0, 2.5, 7.5 and 10 wt%). The temperature and pH stability of the system were determined respectively by measuring particle size, zeta potential and retention of the curcumin loaded in the emulsion after one-week storage in the solutions with different pH and temperature conditions. The average molecular weight of the modified starch decreased with treatment time. The 96h treated rice starch had the lowest molecular weight while the 1h treated starch mainly consisted of high molecular weight components. The storage temperature did not significantly influence the stability of curcumin emulsion. However, the particle size of the emulsion with modified starch slightly increased when stored at acidic pH condition, which might be attributed to starch aggregation. The curcumin retention was higher for the samples with the modified starch than the control at all concentrations. The pH stability of the curcumin was also higher than the control at all pH conditions. Specifically, the 1h treated starch showed the best performance regarding curcumin protection in emulsion, which might be attributed to the high viscosity that retarded the curcumin release. Further research needs to be conducted on the mechanism.

Licorice and rosemary contain a number of natural phenolic compounds which have a strong antibacterial and antioxidant activity. Ulleungdo stonecrop (US, scientific name: Sedum takesimense Nakai), indigenous island, is also known as a good antibiotic agent and skin whitening agent and is regarded as a promising materials in cosmetics field. Although the antibacterial activity of each material have been reported, little is known about the effect of using them together. Therefore, the purpose of this study was to investigate the synergistic effect on antibacterial activity when licorice and rosemary extract and US were used together. Since licorice and rosemary are lipid soluble materials and US is water soluble material, oil in water (O/W) emulsion system was used for this study. To manufacture O/W emulsions containing three kinds materials, first licorice and rosemary extracts and US was dispersed in soy bean oil and phosphate buffer (pH7) respectively. Decaglyceryl laurate was used as an emulsifier. There was slight decrease (-0.09~-0.46 Δlog) in the number of bacteria when O/W emulsion containing 300ppm of each licorice and rosemary extracts was mixed into B.subtilis. However, adding US (2,700ppm) into aqueous phase caused the rapid decrease in the amount of bacteria to -1.71 ~ -2.96 Δlog which were much higher decrement than US only in normal emulsion (-1.64 Δlog). In particular, there was a noticeable synergistic effect when rosemary extract and US was used together. The results obtained from this study could provide useful information for utilizing licorice and rosemary extracts and US as functional materials in the food and cosmetic areas.

O/W emulsion is usually adopted to incorporate lipid-soluble bioactive molecules into water-based food systems. However, the emulsion system solely cannot protect the core compound through the storage period, especially in cases when the core is unstable to environmental stress factors. Wall materials such as maltodexrin and chelators such as EDTA-Na are added to improve the stability of core materials but excessive use of additives may be repulsive to consumers. In this study, water soluble fraction of the crude polysaccharide extracted from Enteromorpha prolifera, a type of green algae commonly found in the southern coast of Korean sea, was added to an O/W emulsion system containing retinol to improve storage stability through different modes of action; as a chelator of metal ions, as a scavenger of free radicals and as a wall material. The radical scavenging ability and chelating ability of E.prolifera polysaccharide were determined in solution state. Particle size, zeta potential and retinol retention rate were measured as stability markers in emulsion. Emulsion stability increased and then decreased as the amount of polysaccharide increased from 1 to 5 mg. This optimum concentration is much lower compared to that of conventional usage of wall materials, therefore less affecting the physical characteristics of emulsion while providing effective protection.

‘용매 이동 유도 상분리‘라는 신 기법을 이용하여 바이젤 중공사막을 개발했고 이를 물/기름 에멀젼 분리에 적용하였다. 바이젤막은 미세유체장치를 이용한 방사법을 통해 제조되며, 제조액으로는 실리카 나노입자가 분산된 삼성분계 혼 합액 (물/가교 가능한 단량체/ 에탄올)을 사용한다. 실리카 나노 입자의 양, 입자 표면을 개질하는 계면활성제의 양에 따라 표면층의 기공 크기 및 하부 층의 구조 변화를 살펴보았다. 바이젤 막의 장점은 후 코팅 공정을 거치지 않고도, 막 표면 전체를 실리카 입자 층으로 덮어 anti-fouling 효과를 보유한다는 점이다. 물/기름 에멀젼에서 순수 물을 얻는 정밀여과에 적용하였으며, 상용 폴리설폰 중공사막보다 우수한 oil rejection 및 투과도를 보여주었다.

이 연구는 국산화 한 액정형성 유화제에 대하여 선진사의 액정형성제를 사용하여 pH변화에 따른 안정성에 관한 것이다. 국산화한 액정유화제는 SugarCrystal-LC (㈜바이오뷰텍, 한국)를 사용하였 고, 비교시료는 Nikkomulese-LC (니코캐미칼즈, 일본)와 Alacel-LC (Croda 캐미칼즈, 영국)를 사용하 여 액정형성의 생성력을 실험하였다. 액정형성은 산성 (pH=4.2)에서, 중성 (pH=7.0) 그리고 알칼리성 (pH=11.7)에서 액정구조가 생성되는지 현미경으로 확인하였다. 또한 교반 속도에 따른 액정의 형성 입 자를 편광현미경으로 관찰 하였다. 교반 시간은 모두 동일하게 3분 동안 Homo-mixer로 교반하였고, 교반속도는 2500rpm, 3500 rpm, 4500rpm으로 증가시켜 액정의 상태를 관찰하였다. 그 결과 한국산 계면활성제가 2종의 외국산 보다 안정하고, 선명한 액정구조가 형성되는 것을 알 수 있었고, 영국산의 경우 유화입경이 분균일하여 불안정한 상태를 보였다. 일본산의 경우, 한국산과 유사한 구조와 성능을 가지고 있음을 알 수 있었다. 한국산 계면활성제는 외국산과 비교하여 우수한 유화성능을 가지고 있음을 알 수 있었다. 응용분야로 국산화한 Sugar Crystal-LC 계면활성제를 사용하여 액정크림, 로션, 아이크림 등 다양한 제형개발이 가능하고, 화장품산업은 물론 의약품산업 및 제약산업에서 피부외용제의 유화기술 로 폭넓게 응용이 가능할 것으로 기대한다.

Retinol is a type of vitamin A that helps the skin's epidermal cells maintain their original function and plays an important role in visual acuity. However, retinol cannot simply be incorporated into foods in its pure form because of limited solubility and chemical instability. In this study, retinol was encapsulated within lipid droplets of oil-in-water (O/W) emulsion and the photo stability of retinol loaded in O/W emulsion was examined. O/W emulsions containing retinol were prepared using Tween 20, Decaglycerine myristate and WPI, respectively, at different oil concentrations (0.1, 0.5, 1.0, 2.0, and 4.0 wt%). Photo stability of retinol was determined by measuring retention rate (%) of retinol loaded in O/W emulsions after exposure to UV light for 24 h and compared to that of retinol dissolved in ethanol. The retinol retention rate was higher for O/W emulsions than retinol in ethanol and the retention rate increased as the oil concentration of emulsions increased, which might be attributed to the opaqueness of emulsions. As the oil concentration of emulsions increased, the turbidity of emulsions also increased. In terms of the type of emulsifier, decaglycerine myristate-stabilized emulsion had the highest retinol retentions rate than other emulsifier-stabilized emulsions after exposure to UV light. This study provides important information for designing effective emulsion-based delivery systems for improving the stability of retinol.

The purposes of this research were to develop water-in-oil-in-water double emulsion (DE) for co-loading EGCG and piperine as its marker compounds, and to determine its physicochemical properties. Stable DE was produced based on our previous research. Briefly, for oil phase (O), olive oil, glycerol ester of wood rosin, polyglycerol polyricinoleate, piperine, and for interior water phase (W1), deionized water, gelatin, sodium chloride, ascorbic acid, and EGCG were mixed and heated up to 60°C. Thereafter, W1 was dispersed into O dropwisely followed by magnetic stirring, high-shear homogenization, and ultrasonication, respectively. Produced water-in-oil primary emulsion (PE) was rested at 4°C for 30 min. For exterior water phase (W2), deionized water, sodium chloride, ascorbic acid, and polyoxyethylene sorbitan monooleate were mixed. Thereafter, PE was dispersed into W2 dropwisely followed by magnetic stirring, ultrasonication, and high pressure homogenization, respectively. The structure of DE was observed through optical and transmission electron microscopy. And the influence of applying time of high pressure homogenization on the stability of DE was determined. Also, in vitro release characteristics of DE was investigated by using HPLC. Optimized stable DE would be an attractive delivery system for co-loading both hydrophilic and lipophilic bioactive compounds simultaneously. And, once developed, it can be applied to the various food applications such as beverage in a wide range of formulations.

PURPOSES:The objective of this study is to evaluate the performance of asphalt mixtures containing inorganic additive and a high content of reclaimed asphalt pavement (RAP).METHODS:The laboratory tests verified the superior laboratory performance of inorganic additive compared to cement, in cold recycled asphalt mixtures. To investigate the moisture susceptibility of the specimens, tensile strength ratio (TSR) tests were performed. In addition, dynamic modulus test was conducted to evaluate the performance of cold recycled asphalt mixture.RESULTS:It was determined that NaOH solution mixed with Na2SiO3 in the ratio 75:10 provides optimum performance. Compared to Type B and C counterparts, Type A mixtures consisting of an inorganic additive performed better in the Indirect tensile strength test, tensile strength ratio test, and dynamic modulus test.CONCLUSIONS:The use of inorganic additive enhances the indirect strength and dynamic modulus performance of the asphalt mixture. However, additional experiments are to be conducted to improve the reliability of the result with respect to the effect of inorganic additive.

PURPOSES :The purpose of this study was to determine the optimum mix design of the content of 100 % reclaimed asphalt pavement (RAP) for spray injection application with different binder types.METHODS:Literature review revealed that spray injection method is the one of the efficient and economical methods for repairing a small defective area on an asphalt pavement. The Rapid-Setting Polymer modified asphalt mixtures using two types of rapid setting polymers-asphalt emulsion and a quick setting polymer asphalt emulsion-were subjected to the following tests to determine optimum mix designs and for performance comparison: 1) Marshall stability test, 2) Retained stability test, 3) Wet track abrasion test, and 4) Dynamic stability test.RESULTS AND CONCLUSIONS :Type A, B, and C emulsions were tested with different mix designs using RAP aggregates, to compare the performances and determine the optimum mix design. Performance of mixtures with Type A emulsion exceeded that of mixtures with Type B and C emulsion in all aspects. In particular, Type A binder demonstrated the highest performance for WTAT at low temperature. It demonstrated the practicality of using Type A mixture during the cold season. Furthers studies are to be performed to verify the optimum mix design for machine application. Differences in optimum mix designs for machine application and lab application will be corrected through field tests.

본 연구는 닭가슴살(5, 15, 25%)과 기계발골 계육(5, 15, 25, 35%)의 첨가 수준을 달리하여 제조한 소 시지의 품질특성을 조사하여 육가공제품의 원료로 적정 첨가 수준을 구명하고자 실시하였다. 닭가슴살을 첨가한 소시지는 수분과 단백질 함량이 증가하였으나, 지방함량이 감소하였다. 기계발골 계육 첨가는 소 시지의 수분과 단백질 함량을 감소시키고, 지방함량을 증가시켰다. 무기물의 경우 닭가슴살 첨가가 소시 지의 인, 나트륨, 구리 함량을 증가시켰으며, 기계발골 계육 첨가는 칼슘, 철 함량을 증가시켰다. 닭가슴 살 또는 기계발골 계육을 첨가한 소시지는 pH를 감소시켰다. 닭가슴살 첨가는 소시지의 명도를 증가시키 고, 적색도와 황색도를 감소시켰으며, 기계발골 계육을 첨가한 소시지는 명도가 감소하고, 적색도와 황색 도가 증가하였다. 조직감에서 닭가슴살 첨가는 경도, 탄력성, 검성, 씹힘성이 증가하였으나, 기계발골 계 육 첨가는 경도, 탄력성, 검성, 씹힘성을 감소시켰다. 관능적 특성에서 기계발골 계육 첨가는 저작감을 감소시켰다. 기계발골 계육 첨가는 육색에는 긍정적인 영향을 미치나, 조직감을 저해시키고 단백질 함량 을 낮추어, 기계발골 계육을 첨가할 경우 5% 이하로 첨가해야 할 것으로 사료된다.

본 연구는 바이오매스를 열분해하여 생성된 수상오일(water soluble oil)을 얻었다. MDO (Marine Diesel Oil)와 수상오일을 유화시켜 생성된 에멀젼 연료의 특성과 배출가스를 연구 하였다. 바 이오매스로는 톱밥을 사용하였고 500 ℃에서 열분해하여 생성된 물과 탄화수소를 응축시켜서 수상오일 을 얻었다. 수상오일을 MDO에 10∼20% 까지 혼합 후 유화시켜 에멀젼 연료를 만들었다. 엔진 배출가 스 측정은 엔진 dinamometer로 실시하였다. 유화연료는 연소실내에서 미세폭발을 일으켜 연료를 잘게 쪼개어 주어 smoke를 감소시킨다. 그리고 물이 연소실내의 기화열을 빼앗아 연소실 내부의 온도를 낮추 어 NOx 생성을 억제하는 효과를 갖는다. ND-13모드의 각 모드별 배출가스온도가 MDO에 비해 유화 연료를 사용했을 때 낮게 나온 것으로 뒷받침 될 수 있었다.유화연료의 함수율이 증가함에 따라 NOx와 smoke의 배출량은 줄어들었으며, 출력도 함수율 증가에 따라 유화연료 자체의 발열량 감소로 인하여 줄어든 것으로 판단된다.ND-13모드에서 MDO 유화연료를 시험한 결과 바이오매스오일 함유량 20%인 유화연료의 NOx 감 소량은 약 25%, smoke의 총감소량은 약 60%, 그리고 약 15%의 출력손실을 확인하였다.

Ginsenosides are sensitive to various factors such as pH, temperature, ionic strength, etc. However, powdery form of ginseng is good to preserve ginsenosides in it compared to the extracted form. In addition, the ginseng powder can provide pickering effect to control emulsion stability as a substitute of emulsifier forming wall on the surface of oil. A ginseng pickering emulsions was prepared by mixing, MCT oil, polysorbate 80 and ginseng. Thereafter, to homogenize the emulsions magnetic stirrer, homogenizer and ultra sonicator were used. The physicochemical properties, stability, and bioaccessibility of the ginseng pickering emulsion were investigated. Both particle size and polydisperse index of the ginseng pickering emulsion were constant as time elapsed. However, pH and zeta-potential of the ginseng pickering emulsion decreased over time. Moreover, to find out the proper amount of ginseng powder, different ginseng powder weights were added to sample respectively and the physiochemical characteristics were measured. The pH and zeta-potential value tended to decrease following increase of amount of ginseng powder. This result is impacted to food quality and it could be used as a preliminary result in the development of food product.