• Title/Summary/Keyword: stability.

Search Result 34,926, Processing Time 0.057 seconds

A Study on the Moisturizing Effect and Preparation of Liquid Crystal Structures Using Sucrose Distearate Emulsifier (슈크로오스디스테아레이트를 사용한 액정구조의 생성과 보습효과에 관한 연구)

  • Kwak, Myeong-Heon;Kim, In-Young;Lee, Hwan-Myung;Park, Joo-Hoon
    • Journal of the Korean Applied Science and Technology
    • /
    • v.33 no.1
    • /
    • pp.1-12
    • /
    • 2016
  • This study is to make the liquid crystalline structure using sucrose distearate (Sucro-DS) emulsifier to create the hydrophilic type oil-in-water (O/W) emulsion, the droplets of the emulsion having a structure of a multi-lamellar structure. We have studied the physicochemical properties of Sucro-DS using those techniques. And it has been studied in the emulsion performance. In order to form the liquid crystalline structure applying 3 wt% of Sucro-DS, 5 wt% of glycerin, 5 wt% of squalane, 5 wt% of capric/caprylic triglyceride, 3wt% of cetostearyl alcohol, 1wt% of glyceryl mono-stearate, 78 wt% of pure water in mixture having the lamellar structure of stable multi-layer system was found to formed. By applying them, they were described how to create an unstable active material encapsulated cream. Further, the moisturizing cream was studied using this technique. It reported the results to the skin improvement effect by the human clinical trials. The pH range to produce a stable liquid crystal phase using a Sucro-DS was maintained in 5.2~7.5. In order to increase the stability of the liquid crystal, it was when behenyl alcohol containing 3 wt%, the hardness at this time was 13 kg/mm,min. Viscosity of the same amount was 25,000mPas/min. After a test for the effects of the emulsions, the concentration of 6 wt% Sucro-DS is that was appropriate, the particle size of the liquid crystal was 4~6mm. It was observed through a microscope analysis, reliability of the liquid crystal changes for 3 months was found to get stable at each $4^{\circ}C$, $25^{\circ}C$ and $45^{\circ}C$. In clinical trial test, before applying a moisturizing effect it was $13.4{\pm}7%$. Moisturizing cream liquid crystal was not formed in $14.5{\pm}5%$. Therefore, applying than ever before could see the moisture about 8.2% was improved. On the other hand, it was the moisturizing effect of the liquid cream is $19.2{\pm}7%$. The results showed that 43.3% improvement than that previously used. Applications fields, Sucro-DS emulsifier used liquid cream, lotion, eye cream and a variety of formulations can be developed, as well as the cosmetics industry is expected to be wide fields in the application of the external preparation for skin emulsion technology in the pharmaceutical industry and pharmaceutical industry.

Quality Changes of Dried Lavers during Processing and Storage 3. Changes in Pigments, Trypsin Indigestible Substrates(TIS) and Dietary Fiber Content during Roasting and Storage (김의 가공 및 저장중의 품질변화 3. 배소 및 저장중의 색소, Trypsin 저해물질(TIS) 및 Dietary Fiber의 변화)

  • LEE Kang-Ho;RYUK Ji-Hee;JEONG In-Hak;JUNG Woo-Jin
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.23 no.4
    • /
    • pp.280-288
    • /
    • 1990
  • Quality stability of dried lavers during roasting and storage was investigated by measuring the changes of pigment contents including chlorophyll a, carotenoids and biliproteins, the content of trypsin indigestible substrates(TIS), in vitro apparent protein digestibility, and dietary fiber. In heat treatment or roasting of dried laver, carotenoids and chlorophyll a were found to be more stable than biliproteins. Chlorophyll a and carotenoids were retained more than $85\%$ during roasting for 1 hour at $120^{\circ}C$ while biliproteins were retained only $10\%$ at the same temperature. The in vitro digestility of dried layers tended to increase with raising the roasting temperature. The in vitro digestibility of $85\%$ for the roasted laver at $100^{\circ}C$ was higher than that observed in the control of $80\%$. There was a correlation between the decrease in TIS and biliproteins as the laver was roasted. The soulble dietary fiber(SDF) content was substantially increased by heat treatment. The extent of protein digestiblility appeared to be related to the increase of SDF content. In the storage of roasted lavers under both water activities 0.1 and 0.65, the loss of the pigments and TlS were markedly retarded at Aw 0.1. Chlorophyll a was retained about $20\%$ at aw 0.65 and $75\%$ at aw 0.1 after 20 week sto-rage. At worst, more than $90\%$ of the carotenoids were lost at aw 0.65 after 20 week, while biliproteins were comparatively stable at the same water activity. TIS decreased about $15\%$ and in vitro apparent protein digestibility increased up to $92\%$ at aw 0.65 during storage.

  • PDF

Studies on Processing ana Keeping Quality of Retort Pouched Foods (3) Preparation and Keeping Quality of Retort Pouched Fried Mackerel Meat Paste (레토르트파우치식품의 가공 및 품질안정성에 관한 연구 (3) 레토르트파우치 튀김어묵의 제조 및 저장중의 품질안정성)

  • LEE Eung-Ho;OH Kwang-Soo;KOO Jae-Geun;PARK Hyang-Suk;CHO Soon-Yeong;CHA Yong-Jun
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.17 no.5
    • /
    • pp.373-382
    • /
    • 1984
  • Processing conditions of retort pouched fried mackerel fish meat paste and quality stability during storage were investigated. The reasonable amounts of added ingredients to the frozen mackerel meat paste were $10\%$ of corn starch, $1\%$ of soybean protein, $1.5\%$ of sodium chloride, $0.6\%$ of monosodium glutamate, $0.3\%$ of alcoholic extract of red pepper, and $0.1\%$ of sodium erythorbate as an antioxidant and also added water corresponding to $10\%$ of the frozen mackerel meat paste. After grinding the defrosted mackerel fish meat paste with ingredients, the meat paste was molded in bar type and fried in soybean oil at $170-180^{\circ}C$ for 3 minutes. The fried mackerel meat paste was cooled, vacuum-packed in laminated plastic film bag (polyester/polyvinylidene chloride/unoriented polypropylene : $12{\mu}m/15{\mu}/50{\mu}m,\;14{\times}19cm$) and finally sterilized at $120^{\circ}C$ for 20 minutes in a hot water circulating retort. The pH, volatile basic nitrogen, moisture content, water activity, color, thiobarbituric acid value, peroxide value, texture and viable bacterial count of products were examined during 100 days of storage at $25{\pm}3^{\circ}C\;and\;5^{\circ}C$. The results showed that products could be preserved in good condition for 100 days at $25{\pm}3^{\circ}C$. Judging from sensory evaluation, the quality of products was not inferior to that of market products.

  • PDF

Negative Support Reactions of the Single Span Twin-Steel Box Girder Curved Bridges with Skew Angles (단경간 2련 강박스 거더 곡선교의 사각에 따른 부반력 특성)

  • Park, Chang Min;Lee, Hyung Joon
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.16 no.4
    • /
    • pp.34-43
    • /
    • 2012
  • The behaviors of the curved bridges which has been constructed in the RAMP or Interchange are very complicate and different than orthogonal bridges according to the variations of radius of curvature, skew angle and spacing of shoes. Occasionally, the camber of girder and negative reactions can be occurred due to bending and torsional moment. In this study, the effects on the negative reaction in the curved bridge were investigated on the basis of design variables such as radius of curvature, skew angle, and spacing of shoes. For this study, the twin-steel box girder curved bridge with single span which is applicable for the RAMP bridges with span length(L) of 50.0m and width of 9.0m was chosen and the structural analysis to calculate the reactions was conducted using 3-dimensional equivalent grillage system. The value of negative reaction in curved bridges depends on the plan structures of bridges, the formations of structural systems, and the boundary conditions of bearing, so, radius of curvature, skew angle, and spacing of shoes among of design variables were chosen as the parameter and the load combination according to the design standard were considered. According to the results of numerical analysis, the negative reaction in curved bridge increased with an decrease of radius of curvature, skew angle, and spacing of shoes, respectively. Also, in case of skew angle of $60^{\circ}$ the negative reaction has been always occurred without regard to ${\theta}/B$, and in case of skew angle of $75^{\circ}$ the negative reaction hasn't been occurred in ${\theta}/B$ below 0.27 with the radius of curvature of 180m and in ${\theta}/B$ below 0.32 with the radius of curvature of 250m, and in case of skew angle of $90^{\circ}$ the negative reaction hasn't been occurred in the radius of curvature over 180m and in ${\theta}/B$ below 0.38 with the radius of curvature of 130m, The results from this study indicated that occurrence of negative reaction was related to design variables such as radius of curvature, skew angle, and spacing of shoes, and the problems with the stability including negative reaction will be expected to be solved as taken into consideration of the proper combinations of design variables in design of curved bridge.

Extraction and Characteristics of Purple Sweet Potato Pigment (자색고구마 색소의 추출과 특성)

  • Kim, Seon-Jae;Rhim, Jong-Whan;Lee, Lan-Sook;Lee, Joon-Seol
    • Korean Journal of Food Science and Technology
    • /
    • v.28 no.2
    • /
    • pp.345-351
    • /
    • 1996
  • Studies on extraction and color characteristics of purple sweet potato (PSP) pigment were performed to provide the basic information for the utilization of PSP as a new source of natural food colorant. PSP pigment was extracted well with the polar solvents such as distilled water, ethanol, and methanol. but hardly extracted with the non-polar solvents. Among the tested solvents, 20% ethanol solution containing 0.1% citric acid was found to be the most efficient for extraction of the pigment from PSP. PSP contained high amount of pigment not only in the epidermis but also in the flesh of the potato. The PSP pigment was heat stable even under pretreatments such as autoclaving and blanching of the potato before extraction. The optimum temperature of the extraction for the PSP Pigment was decided to be $30^{\circ}C$ by considering the stability and the rate of extraction. The pigment was markedly influenced by the change of pH. The color of the pigment solution was red at the pH range of $1.0{\sim}3.0$, became blue at $7.0{\sim}8.0$, then turned green at $9.0{\sim}10.0$. A characteristic batho-chromic shift of the pigment solution was observed as the pH of the solution increased.

  • PDF

Properties of Dietary Fiber Extract from Rice Bran and Application in Bread-making (미강에서 추출한 식이섬유추출물의 특성 및 제빵에의 응용)

  • Kim, Young-Soo;Ha, Tae-Youl;Lee, Sang-Hyo;Lee, Hyun-Yu
    • Korean Journal of Food Science and Technology
    • /
    • v.29 no.3
    • /
    • pp.502-508
    • /
    • 1997
  • Rice bran dietary fiber extract, which was obtained after termamyl treatment of defatted rice bran contained $27.3{\sim}30.5%$ protein, $49.7{\sim}54.1%$ insoluble dietary fiber, and $1.9{\sim}2.7%$ soluble dietary fiber. Extrusion decreased the insoluble dietary fiber content but increased the soluble dietary fiber content, while roasting did not. Influence those content. Each mineral element content was depended upon heat processing method. Extrusion increased the water binding capacity and L value, while roasting reduced the water binding capacity and L value. Scanning electron microscopy showed damaged cell walls for extruded sample compared to roasted one which had fully collapsed cell walls. The increase of water absorption, developing time, and stability and the of MTI of wheat flour-dietary fiber extract composites with addition of dietary fiber extract were observed by Farinograph. Rice bran dietary fiber extract had an effect on the bread making resulting in increase of bread weight and color of crumb and crust, and decrease of bread volume and texture. As a result of sensory evaluation, appearance, texture, overall acceptability were significantly different from control but flavor and taste were not different significantly up to 6% level. Heat treated samples had differences in mean values, but not significant differences statistically.

  • PDF

Comparison of Kinetic Parameters, pH and Thermal Properties of Soluble and Immobilized Transglucosidase from Aspergillus niger (Aspergillus niger 유래의 Soluble과 고정화 Transglucosidase의 속도상수, pH 및 열 특성 비교)

  • Ahn, Jang-Woo;Park, Kwan-Hwa;Seo, Jin-Ho
    • Korean Journal of Food Science and Technology
    • /
    • v.30 no.3
    • /
    • pp.630-637
    • /
    • 1998
  • Enzymatic properties of immobilized transglucosidase (TG) from Aspergillus niger was characterized and compared with soluble TG. Michaelis-Menten constant $(K_m)$ and maximum velocity $(V_{max})$ of immobilized TG were $122\;mM,\;3.9{\times}10^{-2}\;mM/min$ and in case of soluble TG, 21 mM, 0.4 mM/min. The optimum pH of immobilized TG was pH 5.0 like soluble TG but immobilized TG showed 16% and 45% higher activity than soluble TG at pH 5.0 and pH 6.0. Both of immobilized TG and soluble TG were stable from pH 2.0 to pH 9.0, and therefore their activities in these pH ranges were remained more than 90%. The temperature was optimal at $60{\sim}70^{\circ}C\;and\;70{\sim}80^{\circ}C$ for soluble TG and immobilized TG, respectively. The thermal stability of immobilized TG was significantly improved than that of soluble TG, and immobilized TG retained $32{\sim}40%$ higher activity than soluble TG. D-values from thermal inactivation of immobilized TG were 7690 sec at $65^{\circ}C$, 83 sec at $75^{\circ}C$, 7.2 sec at $80^{\circ}C$. Z-values of soluble and immobilized TG were $6.4^{\circ}C\;and\;5.3^{\circ}C$, respectively. The little difference of activation energies of soluble TG and immobilized TG supposed that there was little difference in mass transfer limitation during the reaction of soluble TG and immobilized TG.

  • PDF

Studies on Stability for the Quality of Ginseng Products -2. Comparative Study on Keeping Quality of Red Ginseng Extract Powders(RGEPs) and Commercial Dehydrated Tea Products- (인삼제품(人蔘製品)의 품질안정성(品質安定性)에 관한 연구(硏究) -2. 인삼정분(人蓼精粉)과 시판다류제품(市販茶類製品)의 품질안정성(品質安定性) 비교(比較)-)

  • Choi, Jin-Ho;Byun, Dae-Seok;Ro, Jae-Il;Park, Kil-Dong;Sung, Hyun-Soon
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.13 no.2
    • /
    • pp.209-214
    • /
    • 1984
  • To compare the keeping quality of freeze and spray dried red ginseng extract powders(RGEPs) and commercial dehydrated tea products, particle sizes and initial moisture contents of these products were measured, and the relationships between crude fat contents and moisture contents and/or densities were studied. Particle sires of RGEPs and commercial dehydrated tea products were below 100 mesh, and particle sizes of freeze dried products were higher than those of spray dried products. Initial moisture contents of freeze and spray dried RGEPz were 3.587 and 4.56f, and those of frecze and spray dried coffees were 2.17% and 3.52%, respectively. Crude fat contents of tang and ssanghwa tea were 4.12% and 0.62%, and densities of tang and ssanghwa tea were 0.89 g/ml and 0.59 g/ml, respectively. Absorption rates o( tang and ssanghwa tea were the lowest among these products, it was considered because of crude fat contents of tang and ssanghwa tea were higher than these of the other products, and densities of tang and ssanghwa tea were higher than these of the other products. Notwithstanding absorption rates of RGEPs were lower than those of coffees, to maintain lower keeping quality of RGEPs than that of coffees, it was considered that HGEPs are not only lower to coffees in crude fat contents but also in densities. A sinificant relationships were found between keeping Quality and crude fat content and/or density.

  • PDF

Enzymatic Characteristics of Water-Insoluble ${\alpha}-Amylase$ Immobilized on Dithiocarbamate Wool (Dithiocarbamate Wool에 고정(固定)된 불용성(不溶性) ${\alpha}-Amylase$의 특성(特性)에 대하여)

  • Lee, Kyung-Hee;Kim, Jong-Deog;Lee, Kang-Ho
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.14 no.2
    • /
    • pp.164-170
    • /
    • 1985
  • Yellowish modified wool, dithiocarbamate(DTC) wool, was synthesized by partial hydrolysis in 0.2 N-NaOH reacting with carbon disulfide to use as ${\alpha}-amylase$ immobilization matrix. ${\alpha}-amylase$ was immobilized reacting with sulfide group of DTC-wool by covalent binding within 1 hour. 0.5 gram of this preparation, $DTC-wool-{\alpha}-amylase$, contained 150 ug of enzyme protein and its specific activity was about 90% of the native one. General properties of $DTC-wool-{\alpha}-amylase$ were a little different from optimum temperature, optimum pH, heat stability, kinetic constants and activation energy. An apparent Michaelis constant and maximum velocity of $DTC-wool-{\alpha}-amylase$ were 5.56 mg/ml and 0.37 mg/ml. $min^{-1}$ respectively, while activation energy was 16.6 kcal/mole.

  • PDF

Establishment of Optimal Rearing Conditions for the Production of Tenebrio molitor Larvae (갈색거저리 유충 생산을 위한 효율적인 사육조건 확립)

  • Kim, Sihyeon;Kim, Jong Cheol;Lee, Se Jin;Kim, Jae Su
    • Korean journal of applied entomology
    • /
    • v.55 no.4
    • /
    • pp.421-429
    • /
    • 2016
  • Tenebrio molitor larvae contain large amounts of proteins, lipids and other functional materials, enabling this insect to be used as an edible food source in animal feeds and for industrialization. Although many efforts have been made to set up mass rearing systems, few studies have been conducted to establish optimal rearing conditions for the production of high quality T. molitor larvae. Herein we investigated 1) the effects of additional diets on the survival and fecundity of the insect, 2) the relationship between oviposition period and the uniformity of larval size, 3) the effects of rearing density and temperature on insect development, and 4) the storage stability of eggs and pupae at low temperatures given possible temporary production discontinuation. The addition of carrot and zucchini to the traditional wheat bran diet significantly increased the survival and fecundity rate of adult T. molitor. Of the three different oviposition sampling periods (3, 7, and 14 days) used to investigate the uniformity of the hatched larvae in each treatment, the period of 3 and 7 days provided higher uniformity than the 14 days oviposition period. Larval development was faster at $30^{\circ}C$ than at 20, 25, and $35^{\circ}C$. Interestingly, oviposition rates were highest at $20^{\circ}C$ but showed much slower larval development and lower uniformity at $30^{\circ}C$. Regarding the effect of larval rearing densities (1, 10, 20, 30, 40, and 50 larvae per 90 mm diam. dish), larval weight was significantly reduced at higher rearing densities, but larval longevity and length were not influenced by rearing density. The 30 larvae/dish is suggested to be a reasonable density to be applied to mass production systems. When kept at $4^{\circ}C$, T. molitor eggs showed a significant reduction in hatching rate; however, when stored under the same conditions, pupae emergence rates remained high until 10 weeks, suggesting that storage at low temperatures is more suitable for the pupal stage than the egg stage. Our findings suggest that an increase in T. molitor adult survival and fecundity rates and a uniformity of hatched larval development can be achieved with the following recommendations: a combination diet (including wheat bran), a 7-day oviposition period; a larvae-rearing temperature of $30^{\circ}C$, a rearing density of 30 larvae/dish, and the storage of pupal stages at low temperatures in the case of rearing discontinuation. This study serves as a strong foundation for the successful mass production of high quality T. molitor larvae.