• Journal of the Korean Wood Science and Technology
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• v.43 no.1
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• pp.122-134
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• 2015

This study was conducted to investigate the potential of torrefied larch wood as a raw material of pellets. First of all, larch chip was torrefied at the temperatures of 230, 250 and $270^{\circ}C$ for 30, 50 and 70 min. Secondly, moisture content, moisture absorption, higher heating value and ash content of the torrefied chip were measured to examine the effects of torrefaction conditions on the fuel characteristics of larch. Thirdly, surfaces of the torrefied chip were observed by light microscope (LM), field emission scanning microscope (FE-SEM) and SEM-energy dispersive spectroscopy (EDXS). With the increases of torrefied temperature and time, contents of lignin increased and those of hemicellulose reduced. Moisture content of torrefied larch chip was greatly lower than that of non-torrefied chip. Moisture absorption of the torrefied chip decreased as torrefaction temperature increased. As torrefaction temperature increased, higher heating value and ash content of larch chip increased. However, durability of torrefied-larch pellets was remarkably lower comparing to non-torrefied-larch pellets. When surface of larch chip was observed by LM and FE-SEM, surface color and cell wall of the chip was getting darker and more collapsed with the increases of torrefaction conditions. Through the analysis of SEM-EDXS, distribution and quantity of lignin existing on the surface of larch chip increased with the increases of torrefied conditions. In conclusion, $270^{\circ}C$/50 min might be an optimal condition for the torrefaction of larch with the aspect of fuel characteristics, but torrefaction condition of $230^{\circ}C$/30 min should be considered according to the durability of torrefied-larch pellets.

• Korean Journal of Plant Resources
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• v.22 no.5
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• pp.365-380
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• 2009

Flora of vascular plants in mountains located at Wonju-si and Hoengseong-gun areas such as Chiak-san(1,288m), Taegi-san(1,261.4m), Obong-san(1,126.2m), Eungbong-san(1,094.9m), Eodab-san(789.4m), Deokgo-san(521.2m), Deokga-san(700.5m) and Seongji-bong(791m) was investigated from April, 2008 to May, 2009, and results from the previous researches in which voucher specimens had been presented from Balgyo-san(998.4m), Oeum-san(930.4m), Baekun-san(1,037.1m) and Chiak-san(1,288m) were included in the list of vascular plants from these areas. This investigations resulted in 804 taxa consisted of 680 species, 1 subspecies, 111 varieties, and 12 forms of 383 genera under 97 families, and totally in 973 taxa (21.14% of all vascular plants in Korea) of 818 species, 1 subspecies, 138 varieties and 16 forms of 418 genera under 105 families on addition of voucher specimens in the previous researches. Forests of the investigated areas were generally mixed of Pinus densiflora and deciduous trees. The areas with comparatively excellent vegetation were valley from Guryong-sa (temple) to Biro-bong (summit) via Seryeom-pokpo (fall) in Mt. Chiak-san, and Keunseong-gol (valley) and eastern slope from Taegibungyo-teo to Naksu-dae (fall) in Mt. Taegi-san. 10 families with abundantly collected species were Compositae, Graminae, Rosaceae, Ranunculaceae, Leguminosae, Cyperaceae, Liliaceae, Saxifragaceae, Umbelliferae and Labiatae in order, and they occuied 49.12% of all collected taxa. Endemic plants found in these areas were 38 taxa including Hanabusaya asiatica, Megaleranthis saniculifolia, and Pyrus ussuriensis var. diamantica, and rare and endangered ones were 24 taxa including Hanabusaya asiatica, Viola websteri, Viola diamantica, and Patrina saniculaefolia. Specially designated plants by the Ministry of Environment were 88 taxa including 12 taxa of 5th degree such as Woodsia intermedia, Hanabusaya asiatica, Equisetum pratense, Iris koreana, Lilium cernum, Trillium tschonoskii, Magnolia kobus(cultivated), Gastrodia elata, Polypodium virginianum, Cimicifuga heracleifolia, Megaleranthis saniculifolia and Viola websteri. 47 taxa of alien plants were found. As to 609 taxa (13.23% of all vascular plants in Korea) of useful plants, 334 taxa for the edible, 269 taxa for the medicinal, 127 taxa for the ornamental, 332 taxa for the forage, 3 taxa for the industrial raw material, 31 taxa for the timber and 13 taxa for the fiber were classified, respectively.

• Food Science of Animal Resources
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• v.22 no.3
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• pp.240-246
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• 2002

The seasoned pork with soy sauce(SS) or Kochujang(SK) was manufactured using hind and fore leg as main raw material and the quality characteristics and shelf-life were investigated during storage at 5$\^{C}$ and 10$\^{C}$ after having packaged with air. The initial total aerobic plate counts(APC) of SS and SK were 5.24 and 5.75 log10 CFU/㎠, respectively. APC exceeded 7 log10CFU/cm2 after 10 days at 5$\^{C}$ and 6 days at 10$\^{C}$ far SS, and after 6 days at 5$\^{C}$ and 4 days at 10$\^{C}$ for SK, respectively. In the sensory test, the SS samples stored at 5$\^{C}$ and 10$\^{C}$ were assessed as lower than 3.0 points, the criterium of consumer acceptability, after 10 and 8 days, respectively. In the case of SK samples, the point of this time was at day 10 and 6, respectively when they were stored at 5$\^{C}$ and 10$\^{C}$. As storage time extended, pH and water content tended to decrease. Contrarily, the increase of TBA and VBN values was observed during storage and this was more pronounced at 10$\^{C}$ than at 5$\^{C}$ . The oxygen concentration in the package was 19.8 and 19.9% each for 55 and SK samples at the beginning but it was gradually decreased thereafter. On the other hand, the concentration of carbon dioxide was increased with the extension of storage. Based on the above results, the shelf-lives of seasoned pork were estimated to be 8 days for SS and SK stored at 5$\^{C}$ and 6 days for SS and 4 days for SK stored at 10$\^{C}$.

• Food Science of Animal Resources
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• v.26 no.3
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• pp.297-305
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• 2006

This study was conducted to evaluate the quality characteristics of low-fat emulsion type sausages containing 0% tomato powder (C), 5.0% ground raw tomato paste (T1) and 0.5% freeze dried tomato powder (T2) during storage at $5{\pm}1^{\circ}C$ for 30 days. The crude protein content of T2 was significantly lower (p<0.05) than that of the other sausage types. Moisture, crude fat and crude ash contents of the sausages during storage were not affected by the addition of tomato. The pH and shear force ($kg/cm^2$) values of C were significantly higher (p<0.05) than those of T1 and T2. There was no significant difference among the different sausages in cooking loss, ranging from $13.00{\sim}14.98%$. The WHC values of T1 and T2 were significantly higher (p<0.05) than that of C. The values of TBARS were significantly (p<0.05) increased for ail sausages following storage. The TBARS value (mg MA/kg) of C was significantly higher (p<0.05) than those of T1 and T2 at 15 days of storage, however T1 was significantly higher (p<0.05) than the other sausages after 30 days of storage. The meat color values tended to decrease with increased storage time. Microorganism analysis revealed that all sausage types did not reach $4.4log_{10}CFU/g$ until 30 days of storage. The texture, brittleness, Hardness, and springiness of each sausage type were not significantly different after 1 day of storage, while the cohesiveness, gumminess and chewiness of T1 and T2 were significantly higher (p<0.05) than that of C. T1 and T2 sausages had a slightly higher score regarding color, aroma, tenderness and overall acceptability, however the sensory evaluation score among the different sausage types was not significantly different (p>0.05). In conclusion, low-fat sausage with added tomato showed higher lipid oxidative stability during storage than sausage to which no tomato was added.

• Korean Journal of Food Science and Technology
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• v.27 no.3
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• pp.281-285
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• 1995

The persimmon leaf tea was produced from persimmon leaves by three different methods (conventional, steamed, fermented) and the changes of total vitamin C and superoxide dismutase(SOD)-like activity were investigated. The amount of total vitamin C was the highest in fermented persimmon leaf tea which was 47% of total vitamin C of raw persimmon leaves. The SOD-like activity of conventional and fermented persimmon leaf teas were a little higher than that of steamed. The total vitamin C of steamed persimmon leaf tea was decreased slowly as the extraction time was increased. That of fermented persimmon leaf tea was increased generally at $60^{\circ}C\;and\;70^{\circ}C$, and increased until 5min and then decreased at $80^{\circ}C\;and\;90^{\circ}C$, The optimum extraction condition of total vitamin C in fermented persimmon leaf tea was 3min and 5min at $80^{\circ}C\;and\;90^{\circ}C$, 5min and 10min at $60^{\circ}C$. The total vitamin C of conventional persimmon leaf tea was so little that could not be measured by DNP method. The SOD-like activity of conventional and steamed persimmon leaf teas were increased and that of fermented showed the trend of increasing-decreasing-increasing. Fermented persimmon leaf tea had higher SOD-like activity than conventional and steamed at all tested conditions, and the optimum extraction condition of SOD-like activity was 3min and 10min at $80^{\circ}C\;and\;90^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.411-416
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• 1996

Supercritical fluid extraction of ${\beta}$-carotene from carrot was optimized to maximize ${\beta}$-carotene (Y) extraction yield. A central composite design involving extraction pressure ($X_1$ 200-,100 bar), temperature ($X_2,\;35-51^{\circ}C$) and time ($X_1$$ 60-200min) was used. Three independent factors ($X_1,\;X_2,\;X_3$) were chosen to determine their effects on the various responses and the function was expressed in terms of a quadratic polynomial equation,$Y={\beta}_0+{\beta}_1X_1+{\beta}_2X_2+{\beta}_3X_3+{\beta}_11X_12+{\beta}_22X_3^2+{\beta}_-12X_1X_2+{\beta}_12X_1X_2+{\beta}_13X_1X_3+{\beta}_23X_2X_3,$ which measures the linear, quadratic and interaction effects. Extraction yields of ${\beta}$-carotene were affected by pressure, time and temperature in the decreasing order, and linear effect of tenter point (${\beta}_11$) and pressure (${\beta}_1$) were significant at a level of 0.001(${\alpha}$). Based on the analysis of variance, the model fitted for ${\beta}_11$-carotene (Y) was significant at 5% confidence level and the coefficient of determination was 0.938. According to the response surface of ${\beta}$-carotene by cannoical analysis, the stationary point for quantitatively dependent variable (Y) was found to be the maximum point for extraction yield. Response area for ${\beta}$-carotene (Y) in terms of interesting region was estimated over $10,611{\mu}g$ Per 100 g raw carrot under extraction.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.382-388
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• 1994

Because of its restrictive harvest from spring to summer, It is necessary to preserve raw ascidians, Halocynthia roretzi, for the purpose of processing regardless of season. We evaluated low Temperature tolerance of ascidian and conditions for cold storage to secure the quality of the stock. To retard the browning of meat rapidly occurred after sucking, ascidians were blanched for 10 seconds in 10% boiling salt solution or dipped for 60 seconds in 0.2% $NaHSO_3$ solution, respectively. The samples were stored in ice, at $-17^{\circ}C$ or $-35^{\circ}C$ for 85 days, respectively. Changes in VBN, glycogen, brown pigment formation, total carotenoid, nucleotides and their related compounds during the storage were determined, and sensory evaluation of quality was also practiced. VBN and brown pigment formation were rapidly increased. Glycogen was gradually decreased and then not detectable after 85 days in case of ice storage. Lipophilic brown pigment was higher than hydrophilic and rapidly increased during storage. The result of sensory evaluation showed that the ascidian treated in 0.2% $NaHSO_3$ was good for 85 days of storage at $-35^{\circ}C$ . Judging from the results of chemical experiment and sensory evaluation, the quality of ascidian treated in 0.2% $NaHSO_3$ and stored at $-35^{\circ}C$ was better than that of other samples.

• Journal of Conservation Science
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• v.32 no.4
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• pp.579-588
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• 2016

This study analyzed nonmetallic inclusions in iron swords with a ring pommel excavated in the Ipbuk-dong, Suwon. Scanning electron microscopy with energy dispersive spectroscopy(SEM-EDS) was used to estimate the iron-making temperature, and we compared the oxide with $SiO_2$ to investigate the heat-treatment technology in the production of iron swords with a ring pommel by investigating the artificial insertion of a slag former and the metallurgical structure. From the wustite observed in most of the specimens, it is judged that these swords were produced by heating and forging iron smelted at a low temperature using the solid reduction method. In addition, judging from the partial presence of $P_2O_5$, it is assumed that they were smelted directly with natural ore, not calcined. From the ratios of $CaO/SiO_2$ and $TiO_2/SiO_2$, it is judged that the raw material for iron-making was iron ore and that a calcareous slag former was not artificially inserted. The structure of the blade part on the front end was pure iron. From the high carbon content of the blade part on the ring pommel and the formation of a martensitic structure and pearlite colony, it is judged that they were tempered after carburizing and that the back, handle part, and ring pommel were unintentionally carburized. Judging from the structure of these specimens, it was noted that they were produced by applying artificial partial heat-treatment technology. This study attempted to present a more scientific analysis by using the method of interpretation through component analysis of nonmetallic inclusions appearing in one relic by the ratio of the oxide divided by $SiO_2$. It is judged that reinterpreting the arguments by the results of the existing analysis and research in this way can obtain different interpretations.

• Journal of Astronomy and Space Sciences
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• v.26 no.1
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• pp.89-98
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• 2009

In this study, the YLPODS (Yonsei Laser-ranging Precision Orbit Determination System) is developed for POD using SLR (Satellite Laser Ranging) NP (Normal Point) observations. The performance of YLPODS is tested using SLR NP observations of TOPEX/POSEIDON and CHAMP satellite. JPL's POE (Precision Orbit Ephemeris) is assumed to be true orbit, the measurement residual RMS (Root Mean Square) and the orbit accuracy (radial, along-track, cross-track) are investigated. The validation of POD using GPS (Global Positioning System) raw data is achieved by YLPODS performance and highly accurate SLR NP observations. YGPODS (Yonsei GPS-based Precision Orbit Determination System) is used for generating GPS based precise orbits for TOPEX/POSEIDON. The initial orbit for YLPODS is derived from the YGPODS results. To validate the YGPODS results the range residual of the first adjustment of YLPODS is investigated. The YLPODS results using SLR NP observations of TOPEX/POSEIDON and CHAMP satellite show that the range residual is less than 10 cm and the orbit accuracy is about 1 m level. The validation results of the YGPODS orbits using SLR NP observations of the TOPEX/POSEIDON satellite show that the range residual is less than 10 cm. This result predicts that the accuracy of this GPS based orbits is about 1m level and it is compared with JPL's POE. Thus this result presents that the YLPODS can be used for POD validation using SLR NP observations such as STSAT-2 and KOMPSAT-5.

• Microbiology and Biotechnology Letters
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• v.42 no.3
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• pp.267-274
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• 2014

High pressure processing (HPP) is a non-thermal method used to prevent bacterial growth in the food industry. Currently, pasteurization is the most common method in use for most milk processing, but this has the disadvantage that it leads to changes in the milk's nutritional and chemical properties. Therefore, the effects of HPP treatment on the microbiological and chemical properties of milk were investigated in this study. With the treatment of HPP at 600 MPa and $15^{\circ}C$ for 3 min, the quantity of microorganisms and lactic acid bacteria were reduced to the level of 2-3 log CFU/ml, and coliforms were not detected during a storage period of 15 d at $4^{\circ}C$. An analysis of milk proteins, such as ${\alpha}$-casein, ${\beta}$-casein, ${\kappa}$-casein, ${\alpha}$-lactalbumin, ${\beta}$-lactoglobulin by on-chip electorophoresis revealed that the electrophoretic pattern of the proteins from HPP-treated milk was different from that of conventionally treated commercial milk. While the quantities of vitamins and minerals in HPP-treated milk were seen to be comparable to amounts found in raw milk, the enzyme activity of lipase, protease and alkaline phosphatase after HPP treatment was reduced. These results suggest that HPP treatment is a viable method for the control of undesirable microorganisms in milk, allowing for minimal nutritional and chemical changes in the milk during the process.