• Korean Journal of Optics and Photonics
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• v.21 no.3
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• pp.103-110
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• 2010

A fiber-phase-noise compensating system was constructed for a 1.4 GHz reference frequency transferred through a 13-km-long fiber spool. The transfer instability was dependent on the temperature variation of the compensating system. With the room temperature variation stabilized within $0.3^{\circ}C$, the transfer instability was $4.6{\times}10^{-14}$ at 0.8 s of average time and $2.5{\times}10^{-16}$ at 1000 s of average time with the fiber phase noise compensated. However, with the room temperature changed by $3.5^{\circ}C$, the transfer instability was $6.8{\times}10^{-14}$ at 1.2 s of average time and $3.0{\times}10^{-15}$ at 1000 s of average time. From this result, the temperature stability condition for the experimental setup could be determined to obtain a transfer instability of $10^{-16}$ at 1000 s of average time.

• Food Science and Preservation
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• v.12 no.4
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• pp.372-378
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• 2005

Compare with volatile organic compounds from unirradiated and irradiated dried-red pepper that is representative spice of korea. Volatile compounds from unirradiated and irradiated dried-red pepper were extracted using simultaneous distillation-extraction(SDE) apparatus and analyzed by Gas chromatography/mass spectrometer (GC/MS). A total of 61 and 62 compounds were identified from unirradiated and irradiated dried red pepper at dose of 10 kGy. These compounds included alcohols, aldehydes, furans, hydrocarbons, ketones, N-containing compounds, terpenes and micellaneous compounds. Furfural, benzaldehyde, linalool, nerolidol, ${\alpha}$-curcumene, ${\alpha}$-zingibirene were detected as the major volatile compounds from dried-red pepper. Specially, 1,3-bis[1,1-dimethylethyl]-benzene was confirmed as a marker of irradiated dried-red pepper because is not detected in unirraiatied dried-red pepper.

• Food Science and Preservation
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• v.14 no.2
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• pp.170-176
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• 2007

In this study, extract of Ailanthus altissimawere prepared using hot water under high pressure. The extract were examined for election donating ability (EDA), superoxide dismuase (SOD)-like activity, nitrite scavenging ability (NSA), xanthine oxidase inhibition levels, and tyrosinase inhibition ability. The EDA, using the 1,1-diphenyl-2-picrylhydrazyl method of root extract was 91.25% at 1.0mg/mL. The SOD-like activity of leaf extract was highest at 49.07% and the NSA was 93.33% at pH 1.2, and 85.40% at pH 3.0. The xanthine oxidase inhibitory levels of extracts of A. altissima roots, stems, and leaves were 92.09 97.44% when the extract were tested at 2.0mg/mL. The highest tyrosinase inhibition levels obtained from loot extract were 67.38% at 2.0mg/mL and 63.97% at 0.1mg/mL.

• Food Science and Preservation
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• v.14 no.2
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• pp.124-130
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• 2007

Lettuce (Lactuca Sativa L.) is the most popular salad vegetable crop The purpose of this study was to analyze the quality of lettuce, and residual pesticides in this vegetable, during growth after transplanting. The eatable weight was 40% of the total weight at the commencement of transplanting, but had doubted at harvest after transplanting. As lettuce grew after transplanting, the pH, the sugar level, and the moisture content increased slightly, and the color tended towards yellow rather than greenThe SPDA chlorophyll measurement was 16.84 at 42 day post-ransplantation, and increased to 26.44 at 67 day after transplanting. The contents of vitamin C were 2.5mg/100g wet weight at 60 d after transplantation, but decreased to 2.2mg/100g wet weight 67 day post-transplantation. Mineral (Ca, Fe, K, Mg, and Na) levels rose after transplantation, and attained their highest levels 60 day post-transplantation. The lettuce crop was analyzed for residues of each of 48 pesticides nt 54 after transplantation, and the only such chemical detected was chlorthalonil(0.03 0.25mg/kg wet weight).

• Food Science and Preservation
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• v.14 no.2
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• pp.160-164
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• 2007

This study was performed to investigate the effects of mixing methods, storage period, and dilution ratio of Dangyuja-sugar mixture on the customer preferences for Dangyuja-tea. Most sensory characteristics such as bitterness, flavor, and taste are influenced more by mixing methods of Dangyuja-sugar mixtiue than by storage period. The Dangyuja-sugar mixture prepared by slice cutting is preferred to those prepared by operating electric mixer, The preference test showed that the appearance is not influenced by storage period but by mixing methods, whereas the tne and texture is more affected by storage period in which the 24 month storage is preferred to 12 month storage. therefore, the overall preference fer Dangyuja-tea is the on that prepared with 20% contents of Dangyuja-sugar mixture which is slice-cut and 24 month stored.

• Food Science and Preservation
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• v.19 no.4
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• pp.547-553
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• 2012

Cheongkookjang that was prepared with three kinds of soybeans [non-germinated soybean (NG), soybeans germinated for 12 hr (GS12), and soybeans germinated for 24 hr (GS24)] were investigated. The changes in the pH, total aerobes, and slime content of Cheongkookjangs that were prepared with NG, GS12 and GS24 did not significantly differ during their fermentation for 48 hr at $40^{\circ}C$. The total aerobes of the Cheongkookjang variants reached $10^8{\sim}10^9$ CFU/mL after theirfermentation for 48 hr. The total polyphenol content and DPPH-radical-scavenging activities the germionated and non-germinated soybeans did not significantly differ, but increased significantly according to the germination degree during the fermentation. The isoflavone content of the Cheongkookjang with the germinated soybean increased. The isoflavone content of Cheongkookjang variant were 0.141 mg/g (NG), 0.369 mg/g (GS12) and 0.569 mg/g (GS24); their free amino acid contents were 254.26 mg% (NG), 337.49 mg% (GS12) and 528.78 mg% (GS24); and their sensory characteristics such as their taste, color, flavor, bitter taste, texture, and overall acceptability did not significantly differ.

• Food Science and Preservation
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• v.18 no.6
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• pp.930-937
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• 2011

To develop natural preservatives or functional health foods from soybeans (Baektae and Taekwang), the antioxidant and fibrinoytic activities of the water and 70% (v/v) ethanol extract of soybeans and fermented soybean paste (Chungkukjang) were examined. The polyphenol contents of water extracts from Baektae and Baektae Chungkukjang were 189.25 mg/100 g and 814.58 mg/100 g, respectively, whereas those from Taekwang and Taekwang Chungkukjang were 210.23 mg/100 g and 834.23 mg/100 g. The polyphenol contents of the water extracts from Chungkukjang was 4.0~4.3-fold higher than those from soybean. The electron-donating abilities (EDAs) and superoxide dismutase-(SOD)-like activities of the water and ethanol extracts from Chungkukjang were higher than those of the extracts from soybean. Both extracts were found to have had fibrinolytic activity, and the highest activity was present in the water extracts of Baektae Chungkukjang. The polyphenol contents and antioxidative and fibrinolytic activities of the extracts from Chungkukjang were higher than those of the other soybean extracts. These results indicate that Chungkukjang can be used as a material for health foods or natural antioxidants.

• Food Science and Preservation
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• v.19 no.4
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• pp.492-500
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• 2012

This study was conducted to develop a sauce prepared with sweet pumpkin and Korea Doenjang. The optimum conditions for manufacturing sweet pumpkin-doenjang sauce were investigated using the response surface methodology, based on the central composition design. The amount of stock added, the thickening agent, and doenjang were used as the independent variables, and the sensory characteristics (taste, flavor, color, and overall acceptability) were used as the dependent variables to evaluate the optimum conditions for the preparation of the sauce. The optimum conditions for the maximized-responses variables in the preparation of the sauce were 448.5 g of sweet pumpkin stock, 331.5 g of the thickening agent, and 20.0 g of doenjang. The quality characteristics of sweet pumpkin-doenjang sauce that was manufactured at optimum conditions were as follow: 89.55% moisture content, 0.70% crude protein, 0.10% crude lipids, and 0.71% crude ash. The pH of the sauce was 5.96; total acidity, 0.08%; and soluble solids, 6.80$^{\circ}Brix$. The total polyphenol content of the sauce was 5.70 mg/L. The electron-donating ability and reducing power of the sauce were, 14.24% and 1.64 OD, respectively.

• Food Science and Preservation
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• v.19 no.4
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• pp.594-603
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• 2012

This study developed a high-utility type of vinegar from Rubus coreanus by optimizing its fermentation conditions. In the alcohol fermentation process, the optimal conditions for the maximization of the alcohol contents were an initial sugar concentration of 15 $^{\circ}Brix$, a temperature of $30^{\circ}C$ and 4 days. The optimal conditions for the acetic acid fermentation were 9 days of fermentation at $30^{\circ}C$ and 200 rpm, with 6% alcohol and 2% initial acidity. The sucrose, fructose, and glucose contents were 952.90, 491.01, and 386.62 mg%, respectively. The free organic acids were acetic, malic, succinic, malonic, oxalic, and lactic acids. The total free amino acid content was 104.33 ${\mu}g/mL$, with alanine, glutamic acid, ${\gamma}$-amino-N-butyric acid, and o-phospho-ethanolamine as the major amino acids. The K, Na, and Mg contents were 1,686.10, 172.50, and 69.33 ppm, respectively. The total phenolic and anthocyanin contents were 25.19 and 80.71 mg/100 mL, respectively. The DPPH- and $ABTS^{.+}$ radical scavenging activities were approximately 65 and 94%, respectively. Moreover, the vinegar's ${\beta}$-carotene bleaching activity and reducing power showed that it had strong anti-oxidant properties. These results show that Rubus coreanus vinegar has anti-oxidant properties and may be used as functional food.

• Food Science and Preservation
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• v.18 no.6
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• pp.853-858
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• 2011

Soybean-based food items have been developed as common fermented side dish sauces in South Korea, Japan, and China. Each of these countries, however, has its own fermentation method, including a microorganism-based fermentation process, the mixing of ingredients, the fermentation process, and the mixing of starch. The purpose of this study was to determine the quality characteristics of the commercial product. Fourteen kinds of rice soybean paste (Korea, 2 Japan, 12) were prepared, and their physiochemical properties (ammonium nitrogen, amino nitrogen, amylase, protease, and reducing-sugar contents) were analyzed. JRD-1 was found to contain the highest amount of amino-type nitrogen (426.45 mg%) while KRD-2 showed 316.10 mg%. For the protease activities, the following results were obtained: JRD-9, 695.10 unit/g JRD-11, 671.45 unit/g and JRD-5, 665.03 unit/g. As for the amylase activities, the results that were obtained were JRD-7, 53.65 unit/g JRD-8, 50.71 unit/g KRD-1, 46.52 unit/g JRD-1, 46.29 unit/g and JRD-11, 33.61 unit/g. This research provided information for the quality characteristics of commercial rice soybean paste.