• Title/Summary/Keyword: Storage

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Effects of the Molecular Weight and Type of Chitosans on Shelf-life of Makkulli (막걸리의 저장성에 미치는 분자량별 및 형태별 키토산의 영향)

  • Shin, A-Ga;Jung, Yoo-Kyung;Lee, Ye-Kyung;Kang, Meung-Soo;No, Hong-Kyoon;Kim, Soon-Dong
    • Journal of Marine Bioscience and Biotechnology
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    • v.1 no.4
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    • pp.282-291
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    • 2006
  • Effects of the molecular weight and type of chitosans on shelf-life of Makkulli were evaluated during 18 days of storage at $25^{\circ}C$. Two types of chitosans were studied: ${\alpha}$-chitosans with 11 different molecular weights (water-soluble, Mw = 1, 8, 22, 43, 67 and 616 kDa; acid-soluble, Mw = 282, 440, 746, 1,110 and 2,025 kDa) and ${\beta}$-chitosan (acid-soluble, Mw = 577 kDa). Acid-soluble chitosans were applied as a form of chitosan-ascorbate. All chitosans were added to Makkulli at 0.002% concentration, the optimum concentration established in a preliminary test. Among 12 chitosans, the ${\alpha}$-chitosans with 22 and 440 kDa exhibited stronger antimicrobial effects than did other ${\alpha}$- and ${\beta}$-chitosans. The results for pH, acidity, alcohol concentration, viable cell counts, and sensory evaluation suggested that addition of ${\alpha}$-chitosans with 22 and 440 kDa increased the shelf-life of Makkulli by almost 1 week at $25^{\circ}C$ compared with that of control (without chitosan) and other chitosan-added groups. Extension of Makkulli shelf-life by 1 week is fairly significant in view of the magnitude of the total amount of Makkulli produced in Korea.

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Effect of NaCl on the Stability of Oncolytic Vaccinia Virus (항암 백시니아 바이러스의 안전성에 대한 염화나트륨의 효과)

  • Kim, Seong-Geun;Ran, Gui Shao;Kwon, Hyuk-Chan;Hwang, Tae-Ho
    • Journal of Life Science
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    • v.26 no.1
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    • pp.23-33
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    • 2016
  • Pexa-Vec (JX-594) is a specific cancer-targeted oncolytic and immunotherapeutic vaccinia virus. The purpose of this study was to develop methods to maximize the stability of Pexa-Vec. In short-term instability testing, viral activity was rapidly decreased both at 4℃ and at room temperature (RT), but it was completely restored after sonication followed by vortex. Long-term stability testing of Pexa-Vec in the following liquid formulations was performed: (A) 30 mM Tris/pH 7.6, (B) 30 mM Tris/pH 8.6, (C) 30 mM Tris/pH 7.6, 150 mM NaCl, 15% sucrose, (D) 30 mM Tris/pH 7.6, 15% sucrose, and (E) 30 mM Tris/pH 8.6, 15% sucrose. Viral activity decreased less than 2 log10 at 4℃, and RT was observed in 3 days in B, while viral activity was not decreased even after 4–8 weeks at 4℃ and at 1 week in RT in A, suggesting that neutral pH may be essential to maintain virus stability. The addition of 15% sucrose into A (D) significantly increased viral stability at −20℃, 4℃, or RT, and it was also observed at pH 8.6 (E). The addition of 150 mM NaCl into D (C) significantly increased viral stability in addition to the sucrose effect at 4℃ or RT. Accordingly, the viral activity in formulation C was maintained for 1.5 years at 4℃, and for 1-2 weeks in RT. In conclusion, we propose that formulation C can provide the most adequate condition for the proper storage of vaccinia oncolytic virus.

STUDY ON THE INTERFACE BETWEEN LIGHT-CURED GLASS IONOMER BASE AND INDIRECT COMPOSITE RESIN INLAY AND DENTIN (기저재용 광중합형 글래스아이오노머의 치질 및 복합 레진 인레이에 대한 접착양상)

  • Lee, Song-Hee;Kim, Dong-Jun;Hwang, Yun-Chan;Oh, Won-Mann;Hwang, In-Nam
    • Restorative Dentistry and Endodontics
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    • v.30 no.3
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    • pp.158-169
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    • 2005
  • This study was done to evaluate the shear bond strength between light-cured glass ionomer cement (GIC) base and resin cement for luting indirect resin inlay and to observe bonding aspects which is produced at the interface between them by SEM. Two types of light cured GIC (Fuji II LC Improved, GC Co. Tokyo, Japan and Vitrebond$^{TM}$, 3M, Paul Minnesota U.S.A) were used in this study. For shear bond test, GIC specimens were made and immersed in 37$^{\circ}C$ distilled water for 1 hour, 24 hours, 1 week and 2 weeks. Eighty resin inlays were prepared with Artglass$^{(R)}$ (Heraeus Kultzer Germany) and luted with Variolink$^{(R)}$ II (Ivoclar Vivadent, Liechtenstein). Shear bond strength of each specimen was measured and fractured surface were examined. Statistical analysis was done with one-way ANOVA. Twenty four extracted human third molars were selected and Class II cavities were prepared and GIC based at axiopulpal lineangle. The specimens were immersed in 37$^{\circ}C$ distilled water for 1 hour, 24 hours, 1 week and 2 weeks. And then the resin inlays were luted to prepared teeth. The specimens were sectioned vertically with low speed saw. The bonding aspect of the specimens were observed by SEM (JSM-5400$^{(R)}$, Jeol, Tokyo, Japan) .There was no significant difference between the shear bond strength according to storage periods of light cured GIC base. And cohesive failure was mostly appeared in GIC On scanning electron micrograph, about 30 - 120 $\mu$m of the gaps were observed on the interface between GIC base and dentin. No gaps were observed on the interface between GTC and resin inlay.

Rheological Properties of ${\beta}-Glucan$ Isolated from Non-waxy and Waxy Barley (메성 및 찰성보리 ${\beta}-Glucan$의 리올로지 특성)

  • Choi, Hee-Don;Park, Yong-Gon;Jang, Eun-Hee;Seog, Ho-Moon;Lee, Cherl-Ho
    • Korean Journal of Food Science and Technology
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    • v.32 no.3
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    • pp.590-597
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    • 2000
  • The rheological properties of ${\beta}-glucans$ isolated from non-waxy and waxy barley were investigated. ${\beta}-Glucan$ solutions showed pseudoplastic properties and their behaviors were explained by applying Power law model in the range of concentrations$(1{\sim}4%)$ and temperatures$(20{\sim}65^{\circ}C)$. The effects of temperature and concentration on the apparent viscosity at $700\;s^{-1}$ shear rate were examined by applying Arrhenius equation and power law equation, and their effect was more pronounced in waxy ${\beta}-glucan$ solutions. The activation energy for flow of ${\beta}-glucan$ solutions decreased with the increase of concentration, and the concentration-dependent constant A increased with the increase of temperature. The intrinsic viscosity of waxy ${\beta}-glucan$ was higher than that of non-waxy ${\beta}-glucan$. The transition from dilute to concentrate region occurred at a critical coil overlap parameter $C^*[{\eta}]=0.02.$ The slopes of non-waxy and waxy ${\beta}-glucan$ at $C[{\eta}] were similar, but the slope of waxy ${\beta}-glucan$ at $C[{\eta}]>C^*[{\eta}]$ was higher than that of non-waxy ${\beta}-glucan$. Dynamic viscoelasticity measurement showed that cross-over happened, and storage modulus was higher than loss modulus at frequency range above cross-over. ${\beta}-Glucan$ solutions formed weak gels after stored for 24 hr.

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Moisture Sorption Characteristics of Powdered Soybean Curd (분말(粉末) 두부의 수분흡착(水分吸着) 특성(特性))

  • Kim, Dong-Man;Chang, Kyu-Seob;Yoon, Han-Kyo
    • Korean Journal of Food Science and Technology
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    • v.12 no.4
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    • pp.292-298
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    • 1980
  • In order to improve the storage stability of powdered soybean curd, moisture sorption characteristics of the curd stored at specific relative humidity and temperature were investigated. The results obtained are summarized as follows; 1. When the fresh soybean curd (2cm thickness) was dried in a hot air drier at $55^{\circ}C$, it took 18 hrs to reduce its moisture content from 85% to 8.8%, and drying rate was very high during the first 5 hrs. 2. Equilibrum moisture content (E.M.C.) of powdered soybean curd by freeze drying was higher than that of sample by got air drying, but the particle size did not influence E. M. C. 3. The monolayer value of freeze dried powder of high E. M. C was higher than that of the hot air dried(8.30 vs 7.35). 4. The free energy for moisture absorption of freeze dried powder at 11% RH were 1285.1 cal/mole, 1323.5 cal/mole at $15^{\circ}C$ and $30^{\circ}C$, respectively, and the free energy of freeze dried product was lower that of hot air dried product. 5. The moisture sorption rate constant was not affected by particle size, and it showed that the moisture sorption rate decreased as temperature was increased. The rate constant of powder produced by freeze drying were 0.00804 at $15^{\circ}C$ and 0.00696 at $30^{\circ}C$.

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Comparison of the Antioxidant Activity of Absolute Ethanol Extracts and 90% Ethanol Extracts obtained at Successive Stages of a Maillard-type Browning Reaction Mixture (Maillard 형(型) 갈색화(褐色化) 반응액(反應液)에서 얻어진 Absolute Ethyl Alcohol 과 90% Ethyl Alcohol 추출물(抽出物)의 항산화효과(抗酸化效果)의 비교(比較))

  • Lee, Sung-Soo;Rhee, Chul;Kim, Dong-Hoon
    • Korean Journal of Food Science and Technology
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    • v.7 no.1
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    • pp.37-42
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    • 1975
  • The color intensity (Absorbance at 490nm) and the antioxidant effects of absolute and 90% ethanol extracts obtained from a Maillard-type browning reaction mixture (0. 5M glucose and 0. 5M glycine mixture, heated at $100^{\circ}C$) were determined. The color intensity of the absolute and 90% ethanol extracts were compared with the length of reaction time and the antioxidant effects of the extracts of both types were compared one another. The results obtained are as follows. 1. The color intensity of the absolute ethanol extracts remained almost unchanged as the browning reaction proceeded. The color intensity of the 90% ethanol extracts appeared to increase nearly in proportion to the length of reaction time. 2. The absolute and the 90% ethanol extracts seemed to possess significant antioxidant activity on the autoxidation of an edible soybean oil. which was kept at $45{\pm}0.5^{\circ}C$ for 21 days. It was noteworthy that the absolute ethanol extracts showed stronger antioxidant effects than those of the 90% ethanol extracts, which contained a far greater amount of brown-colored pigments. Since the PVs of the controls in both groups, after the end of the storage period, did not differ much from one another, the possibility of residual water playing some prooxidant role in the substrates containing the 90% ethanol extracts should be ruled out. Extracts of both types obtained at earlier stages of the brownig reaction demonstrated less but comparable antioxidant activity to that of extracts taken at later stages of the reaction. 3. The results of the present study appeared to suggest that the effective antioxidant compounds, produced in the Maillard-type browning reaction, were probably intermediate products such as reductones formed at fairly earlier stages of the browning reaction.

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Effects of NaCl Concentration on the Rancidity Development of Sample Ramyon Products, Deep-Fried Instant Noodles (라면 시제품(試製品)의 산패(酸敗)에 미치는 소금 농도(濃度)의 영향(影響))

  • Kim, Tae-Woong;Heo, Tae-Ryeon;Kim, Dong-Hoon
    • Korean Journal of Food Science and Technology
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    • v.7 no.1
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    • pp.51-56
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    • 1975
  • The effects of various concentration of NaCI, i.e., 1, 2, 2. 5, 3, and 4%, on the rancidity development of samples of Ramyon, deep-fried instant noodles, were studied. Dough for the samples, which was composed of wheat flour, distilled water, and pure NaCI, was prepared at a commercial plant but the deep-frying p개cess for the dough was performed in the laboratory. The products thus obtained were incubated for 50 days at $45.0{\pm}1.0^{\circ}C$. Peroxide and TBA values were determined every 5 days throughout the storage period. The results obtained are as follows. 1) Control and the samples containing 1, 2, 2. 5, and 3% salt had POVs of 8. 7, 9. 1, 9. 0, 9. 2 and 9. 7 respectively after 25 days. The control showed a POV of 19.1 after 45 days whereas the sample Ramyons containing 1, 2, 2. 5, 3, and 4% salt had POVs of 12. 6, 13. 2, 14. 6, 15. 3, and 15. 8 respectively after 30 days. 2) TBA values of Control and the sample containing 1, 2, 2. 5, 3, and 4% salt were 5. 8, 6. 1, 6. 2, 6. 4, 6. 7, and 6. 6 respectively after 15 days. But the control developed a TBA value of 11. 4 after 40 days. The samples containing 1, 2, 2. 5, and 3% salt showed TBA values of 10. 2, 14. 3, 15. 8, and 15. 3 respectively after 30 days whereas the sample containing 4% salt had a TBA value of 13. 8 after 25 days. 3) The relationship between the POVs and the TBA values was linear. However, the regression curves of the POVs and the TBA values indicated progressive increase in the gradients(POV/TBA) with increase in the salt content. 4) From the results of the present study, it was found that although the acceleration of rancidity was not in proportion to the amount of NaCI, definite progressive increase in the rancidity development was observed with increase in the salt content of the sample Ramyons.

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Wearable Computers

  • Cho, Gil-Soo;Barfield, Woodrow;Baird, Kevin
    • Fiber Technology and Industry
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    • v.2 no.4
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    • pp.490-508
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    • 1998
  • One of the latest fields of research in the area of output devices is tactual display devices [13,31]. These tactual or haptic devices allow the user to receive haptic feedback output from a variety of sources. This allows the user to actually feel virtual objects and manipulate them by touch. This is an emerging technology and will be instrumental in enhancing the realism of wearable augmented environments for certain applications. Tactual displays have previously been used for scientific visualization in virtual environments by chemists and engineers to improve perception and understanding of force fields and of world models populated with the impenetrable. In addition to tactual displays, the use of wearable audio displays that allow sound to be spatialized are being developed. With wearable computers, designers will soon be able to pair spatialized sound to virtual representations of objects when appropriate to make the wearable computer experience even more realistic to the user. Furthermore, as the number and complexity of wearable computing applications continues to grow, there will be increasing needs for systems that are faster, lighter, and have higher resolution displays. Better networking technology will also need to be developed to allow all users of wearable computers to have high bandwidth connections for real time information gathering and collaboration. In addition to the technology advances that make users need to wear computers in everyday life, there is also the desire to have users want to wear their computers. In order to do this, wearable computing needs to be unobtrusive and socially acceptable. By making wearables smaller and lighter, or actually embedding them in clothing, users can conceal them easily and wear them comfortably. The military is currently working on the development of the Personal Information Carrier (PIC) or digital dog tag. The PIC is a small electronic storage device containing medical information about the wearer. While old military dog tags contained only 5 lines of information, the digital tags may contain volumes of multi-media information including medical history, X-rays, and cardiograms. Using hand held devices in the field, medics would be able to call this information up in real time for better treatment. A fully functional transmittable device is still years off, but this technology once developed in the military, could be adapted tp civilian users and provide ant information, medical or otherwise, in a portable, not obstructive, and fashionable way. Another future device that could increase safety and well being of its users is the nose on-a-chip developed by the Oak Ridge National Lab in Tennessee. This tiny digital silicon chip about the size of a dime, is capable of 'smelling' natural gas leaks in stoves, heaters, and other appliances. It can also detect dangerous levels of carbon monoxide. This device can also be configured to notify the fire department when a leak is detected. This nose chip should be commercially available within 2 years, and is inexpensive, requires low power, and is very sensitive. Along with gas detection capabilities, this device may someday also be configured to detect smoke and other harmful gases. By embedding this chip into workers uniforms, name tags, etc., this could be a lifesaving computational accessory. In addition to the future safety technology soon to be available as accessories are devices that are for entertainment and security. The LCI computer group is developing a Smartpen, that electronically verifies a user's signature. With the increase in credit card use and the rise in forgeries, is the need for commercial industries to constantly verify signatures. This Smartpen writes like a normal pen but uses sensors to detect the motion of the pen as the user signs their name to authenticate the signature. This computational accessory should be available in 1999, and would bring increased peace of mind to consumers and vendors alike. In the entertainment domain, Panasonic is creating the first portable hand-held DVD player. This device weight less than 3 pounds and has a screen about 6' across. The color LCD has the same 16:9 aspect ratio of a cinema screen and supports a high resolution of 280,000 pixels and stereo sound. The player can play standard DVD movies and has a hour battery life for mobile use. To summarize, in this paper we presented concepts related to the design and use of wearable computers with extensions to smart spaces. For some time, researchers in telerobotics have used computer graphics to enhance remote scenes. Recent advances in augmented reality displays make it possible to enhance the user's local environment with 'information'. As shown in this paper, there are many application areas for this technology such as medicine, manufacturing, training, and recreation. Wearable computers allow a much closer association of information with the user. By embedding sensors in the wearable to allow it to see what the user sees, hear what the user hears, sense the user's physical state, and analyze what the user is typing, an intelligent agent may be able to analyze what the user is doing and try to predict the resources he will need next or in the near future. Using this information, the agent may download files, reserve communications bandwidth, post reminders, or automatically send updates to colleagues to help facilitate the user's daily interactions. This intelligent wearable computer would be able to act as a personal assistant, who is always around, knows the user's personal preferences and tastes, and tries to streamline interactions with the rest of the world.

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Field Assessment of Sanitation Management for School Foodservice Suppliers in the Seoul Area (서울지역 학교급식 식재료 납품업체 위생관리 실태 평가)

  • Lee, Kyung-Mi;Ryu, Kyung
    • Korean journal of food and cookery science
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    • v.23 no.5
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    • pp.650-663
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    • 2007
  • The purpose of this study was to identify the sanitation management items of school foodservice suppliers that require improvement, by assessing their sanitation practices with food commodities. Our field assessment was performed using a total of 20 vendors supplying agricultural products, meat products, seafoods and processed products; all were located in the Seoul and Gyeonggi areas. The assessment tool for sanitation management was composed of 93 checklist items and was used to evaluate seven different categories; the facility and environment, management of the facility and equipment, food materials management, process control, water management, personal hygiene management, and laboratory instrument management. A score of two was given for "satisfactory", one for "fair", and zero for "unsatisfactory". The overall average supplier score was 1.7/2.0 (85.8%). The score of the seafood vendors was highest at 1.9 (95.4%), while the lowest score of 1.3 (65.7%) occurred with the processed product suppliers. Among the sanitation management categories, water management was scored at 2.0, while inspection management was lowest at 1.4. The subcategories indicating needed improvements for the processed product suppliers were raw materials, storage, transport and recall. For the agricultural product suppliers it was preparation management. furthermore, one item within the laboratory instrument management category was unsatisfactory for both the agricultural and processed product suppliers. In conclusion, these results can be used to develop sanitation management procedures for suppliers, as well as by administration agencies to evaluate and guide those suppliers.

Estimation of storability for Korean apples (Malus domestica) using Md-ACS1 and Md-ACO1 DNA marker (Md-ACS1 및 Md-ACO1 분자표지를 이용한 국내육성사과의 저장성 예측)

  • Kwon, Young Soon;Kwon, Soon-Il;Kim, Seon Ae;Kweon, Hun-Joong;Yoo, Jingi;Ryu, Seulgi;Kang, In-Kyu;Kim, Jeong-Hee
    • Food Science and Preservation
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    • v.24 no.7
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    • pp.891-897
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    • 2017
  • Apple (Malus domestica) is a climacteric fruit because of its high respiration and ethylene production. Ethylene affects the fruit by decreasing its quality and storability. Md-ACS1 and Md-ACO1 genes are involved in ethylene biosynthesis in apple; the Md-ACS1-2 and Md-ACO1-1 alleles are associated with low ethylene production. We conducted an analysis to study Md-ACS1 and Md-ACO1, and to examine ethylene production and softening rate of fruit at room temperature ($20^{\circ}C$) storage in 'Fuji (FJ)', 'Golden Supreme (GS)', and 5 cultivars of Korean apples ('RubyS (RS)', 'Hongro (HR)', 'Arisoo (AS)', 'Summer King (SK)', 'Greenball (GB)'). The result showed that an increase in the number of the alleles (ACS1-2, ACO1-1) decreased the ethylene production and softening rate. The presence of ACS1-1/1, ACO1-1/2 was confirmed in GS and the highest ethylene production and softening rate was observed. Ethylene production and softening rate of SK and GB expressing ACS1-1/2, ACO1-1/2 were higher than that of HR and AS, expressing ACS1-2/2, ACO1-1/2, but lower than GS. FJ with ACS1-2/2, ACO1-1/1 showed the lowest ethylene production and softening rate among all cultivars except RS. The Md-ACS1 and Md-ACO1 DNA markers could potentially be used to estimate storability and applied in marker assisted selection the improve the efficiency of apple breeding.