• Journal of the Korean Society of Food Culture
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• v.12 no.1
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• pp.63-69
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• 1997

This study was carried out in order to analyzed the changes in nitrogen containing taste compounds of three different types of traditional Korean soy sauce with varing ripening period, and to investigates correlation between sensory characteristics and taste compounds contents via contents assay and sensory evaluation of soy sauce samples. Total nitrogen, ammonia type nitrogen and amino type nitrogen contents showed the highest value in Kyupjang. 17 kinds of free amino acid was detected in Chungjangs and 16 kinds of free amino acid was detected in Kyupjang. Nucleotides and their related compounds detected were hypoxanthin, xanthin, IMP, AMP, Inosine, ADP. Free amino acid and nucleotides and their related compounds contents were highest in Kyupjang. Nitrogen related compounds content of high concentration soy sauce ripened over 150 days increased similarly with Kyupjang. In the sensory evaluation of soy sauce taste, Chungjang samples acquired the highest score in the offensive taste test while Kyupjang marked highest score for sweet taste, nutty taste, taste preference. High concentration soy sauce ripend over 150 days yielded the result similar to that of Kyupjang. Sweet taste showed positive correlation with nitrogen compounds. The materials that showed positive correlation with nutty and traditional soy sauce taste and taste preference were nitrogen compound, IMP, AMP. Except for tryptophan, all free amino acid showed positive correlation with nutty and traditional soy sauce taste. Particulary, taste preference correlated to lysine, aspartic acid and glutamic acid.

• Polymer(Korea)
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• v.26 no.4
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• pp.535-542
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• 2002

We have prepared the surfactant-free nanoparticles of poly(DL-lactide-co-glycolide) (PLGA) by dialysis method and their physicochemical properties such as particle size and drug contents were investigated against various solvent. The size of PLGA nanoparticles prepared by using dimethylacetamide (DMAc), dimethylformamide (DMF), and dimethylsulfoxide (DMSO) was smaller than that from acetone. Also, the order of drug contents was DMAc>DMF>DMSO=acetone. These phenomena could be expected from the fact that solvent affects the size of nanoparticles and drug contents. The PLGA nanoparticles have a good spherical shapes as observed from scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Also, surfactant-free nanoparticles entrapping norfloxacin (NFx) have a good drug loading capacity without free-drug on the surface of nanoparticles confirmed by the analysis of X-ray powder diffraction. Release kinetics of NFx used as a model drug was governed not only by drug contents but also by particle size. Also, the biodegradation rate of PLGA nanoparticles prepared from DMF was faster than that prepared from acetone, indicating that the biodegradation of PLGA nanoparticles is size-dependent.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.4
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• pp.387-396
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• 2004

It was investigated to study the sensory and physicochemical properties of chicken consomme made with different boiling time(1, 2, 3, and 4 hr). The sensory properties were evaluated with respect to both the acceptability (color, smell, mouthfeel, taste, overall acceptability) and intensity characteristics (color, smell, clarify, taste). From the results, the 3hr treatment was most favored for smell, mouthfeel, taste and overall acceptability, from the sensory evaluation tests. According to a quantitative descriptive analysis of the sensory evaluation for the treatments, the color and smell showed higher scores by increasing the boiling time. Whereas, in clarify and taste, the 3hr treatment showed the highest values. As for the physicochemical characteristics, the pH was increased with increasing boiling time. The reducing sugars, turbidity and viscosity increased with increasing boiling time. The colorimetric lightness values L decreased, and redness a, yellowness b and color difference values ΔE increased with increasing boiling time. There were 18 free amino acids indentified ； the glutamic acid, alanine, arginine and lysine were high in the free amino acid of the chicken consomme made with different boiling times. There were 3 free sugar indentified, glucose, fructose and sucrose. The free amino acid and free sugars contents increased with increasing boiling time. There were changes in the mineral contents of the chicken consomme made with different boiling time ; with high K, Na, P, Mg, Ca and Fe contents. The mineral contents increased with increasing boiling time. Especially, the 3hr treatments was more highly increased than rest of the treatments in all characteristics. The results showed the chicken consomme made by boiling far 3hr was the most preferably in the sensory and physicochemical quality.

• Food Science and Preservation
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• v.14 no.6
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• pp.624-632
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• 2007

Changes in proximate composition, amino acid, free sugar, reducing sugar and vitamin contents of Curcuma longa L. (autumn woolgeom in Korean) and Curcuma atomatica Salib (spring woolgeom) were investigated according to picking time. Moisture, crude ash, crude protein and crude lipid were increased and non nitrogen substances was decreased by extending the picking time. Contents and ratio of total amino acid to essential amino acids was increased by extending the picking time. Free amino acid was increased by extending the picking time. Ratio of essential amino acids to total amino acids was decreased. Fructose was gradually increased, and then glucose, sucrose and total free sugars were decreased by extending the picking time. Amino acid and sugar contents of Curcuma longa. L. were higher than those of Curcuma atomatica Salib. In contents of vitamin C and $B_1$, Curcuma longa L. was decreased and Curcuma atomatica Salib was increased by extending the picking time.

• Journal of the Korean Society of Food Culture
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• v.31 no.6
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• pp.643-651
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• 2016

This study was investigated the difference in the quality characteristics of the fermented soybean roasted with different conditions for making chungyukjang. Roasted condition of soybean was decided by pre-test, which was on $140^{\circ}C$ for 21 min, $180^{\circ}C$ 9.5 min, and $220^{\circ}C$ 6 min. Fermented soybean with different roasted condition and conventionally made cheonggukjang were measured for proximate composition, color, pH, amino nitrogen, ammonia nitrogen, free sugar and amino acids. The lightness and yellowness of soybean fermented by conventional method was higher than those of the fermented soybean with roasted soybean. The contents of free sugar of fermented soybean roasted on $220^{\circ}C$ for 6 min (FS220) was the highest among the group and followed by fermented soybean roasted on $180^{\circ}C$ for 9.5 min (FS180), $140^{\circ}C$ 21 min (FS140) and conventional cheonggukjang (FS0). The contents of total free amino acid was highest on fermented soybean roasted on $140^{\circ}C$ for 21 min (FS140) and followed by fermented soybean roasted on $180^{\circ}C$ for 9.5 min (FS180), $220^{\circ}C$ 6 min (FS220) and conventional cheonggukjang (FS0).

• Journal of the Korean Society of Food Culture
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• v.11 no.3
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• pp.385-392
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• 1996

The soluble solid of red pepper was extracted by water in order to investigate changes of soluble solid content by different extraction temperature $(4{\sim}90^{\circ}C)$ and time $(1/2{\sim}3\;hrs)$, and the contents of carotenoid, capsaicinoids, free sugar, organic acid, free amino acid in soluble solid were measured. Most of soluble solid in red pepper was extracted within the first 2 hrs and $93{\sim}98%$ of total soluble solid was extracted during the first 30 min. The contents of carotenoid increased by increasing extraction time and temperature, but decreased by increasing extraction time at $60^{\circ}C$ and $90^{\circ}C$. ${\beta}$-carotene content was sharply decreased after 2 hrs at $90^{\circ}C$. The content of capsaicinoid was sharply increased between 1 hr and 2 hr. Fructose and glucose in red pepper were extracted in the range of $83.8%{\sim}96.4%$ and the contents of free sugar gradually increased by increasing extraction time and temperature. The content of organic acid was gradually increased by increasing extraction time and temperature and the greatest amount of organic acid was extracted during the first 30 min of extraction time. The content of free amino acid was decreased by increasing extraction temperature.

• Journal of Adhesion and Interface
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• v.8 no.4
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• pp.8-13
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• 2007

In this study, solvent-free waterborne polyurethanes (SWPU) were synthesized with teramethylxylene diisocyanate (TMXDI), poly(tetramethylene glycol) (PTMG) and polycarprolactone (PCL) and different mole ratio of dimethylol proponicacid (DMPA). The effect of ionic contents in the solvent-free waterborn polyurethane on thermal, mechanical properties and adhesion strength were studied. Glass transition temperature (Tg) were in range of $-70{\sim}-50^{\circ}C$ and increased as PCL contents increased in polyol. With more incorporation of PCL and DMPA contents in SWPU, tensile strength, adhesion strength and heat resistance of SWPU increased, while the elongation decreased.

• Journal of the Korean Ceramic Society
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• v.41 no.9
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• pp.647-652
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• 2004

In aqueous tape casting of alumina slurry systems, the relationships between the suspension compositions and the defects of the dried tapes were discussed. The suspensions compositions were controlled with the ratios of the solids, water and organics binder contents. The effects of the thickness of dried tape and kinds of binder system were also examined. In the defect free region, the apparent viscosity showed nearly same value due to the count balancing effect of solid and organic binder content on the apparent viscosity. When water content was constant, increasing solid led to decrease of organic binder content. The defect free region was narrowed with increasing of casting thickness. When linear type acrylic emulsion binders system (D1000 and D 1035) were used, defect free zone formed the belt type in the triangle of solid, water and organic binder content according to the line of constant water contents. However the defect free region was not found in the cross-link type emulsion binder system (D 1050).

• Journal of Nutrition and Health
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• v.20 no.6
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• pp.456-462
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• 1987

Chemical composition, free amino acid and fatty acid composition of wild and cultured cockle clam were studied. 1. The content of crude protein was higher in Anadara suberenata thanthat ini Anadara granosa. The contents of crude protein and ash increased after boiling. 2 Free amino acid composition of Anadara granosa was similar to that of Anadara suberenata. Both glutamic acid and aspartic acid among free amino acid were the most abundant in cockle clam. Next, leucine, arginine and lysine were abundant in order. They all composed of approximately 50%^ of total amino acid content. Whereas the contents of cystine and methionine were poor. 3. In cockle clam the major fatty acids consisted of C16 :0, C18: 0, C18 ;1 and C18:3 in order. The level of C16 :0 was the highest in lipids. The levels of C18 : 0 and C14 :0 were higher in Anadara granosa than those in Anadara suberenata, while the levels of C16 :0, C18 :3 and C16 : 1 were higher in Amadara suberenata than those in Anadara granosa.

• Journal of the Korean Society of Food Culture
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• v.4 no.2
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• pp.181-184
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• 1989

The compositions of total and free amino acids in parts of Omija were investigated. The most abundant amino acids in fruits, endocarps, and seeds were arginine (50.80%), lysine (14.37%), glutamic acid (14.22%), respectively. Since the amino acid scores of fruits, endocarps, and seeds were 9.4, 11.9, and 16.7, respectively, the limiting amino acid of each part were S-compound amino acids. In the composition of free amino acids, contents of lysine were highest one such as 51.78, 57.00 and 32.88% in fruits, endocarps and seeds, respectively. The contents of histidine from free amino acids were 23.62% in fruits, 22.37% in endocarps, and 26.41% in seeds.