• Food Science and Preservation
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• v.6 no.4
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• pp.481-487
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• 1999

This study was determined to change in chemical composition of Mume(Prunus mume Sieb. et Zucc) fruits during maturation. There were no differences in the soluble solid and moisture content among varieties, but the soluble solid slowly increased with maturing. The pH and ash content were slightly decreased with maturation. The green color of 'Nanko' fruits was maintained for 92days after full bloom at the greeness value of -3.81 Whereas, the chlorophyll content of 'Koume' fruits remarkably decreased and it was not suitable for the processing of immature green Mume fruits. The titratable acidity increased during maturation. The organic acids were mainly composed of malic acid and citric acid. The malic acid was significantly decreased during maturation, whereas citric acid increased. Major free sugars and sugar alcohols were sucrose, glucose, fructose, sorbitol and maltose. Sucrose content increased as the maturity proceeded, whereas glucose and sorbitol were decreased. The total contesnt of free amino acids decreased with maturation and the total free amino acids in the flesh of fruits were occupied by asparagine at the range of 60 to 78%.

• Journal of the Korean Chemical Society
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• v.33 no.4
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• pp.426-430
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• 1989

Amino alcohol-derived thiazolidinethiones [4-(S)-IPTT, 4(S)-ETT] serve as efficient chiral auxiliary in tin medicated aldol condensation. A highly enantioselective aldol-type reaction forming various ${\beta}$-hydroxy carbonyl compounds from 3-acetylthiazolidine-2-thione and achiral aldehyde is achieved via divalent tin enolate. The other advantages of these chiral auxiliaries were the ease of removal by methanolysis.

• Journal of environmental and Sanitary engineering
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• v.4 no.2 s.7
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• pp.27-32
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• 1989

In orde to investigate free sugar, sugar alcohol, amino acid and mineral contents of edible mushrooms, hentinus edodes, Auricula-Jude and Coriolus Versicolor were analyzed. 1. In each of the three mushrooms, glucose, fructose, xylose, trehalose, mannose and mannitol were identified and in the hentinus edodes and Auricula-jude, the major free sugar was trehalose, respectively and increasing sequence in amount of free sugars were mannitol, mannose, fructose, glucose, on the other hand that lowest amount was Xylose. The relatively richest were glucose, fructose, trehalose, mannose, on the other hand lower amount of sample, Coriolus Versicolor were mannitol and Xylose. 2. In each of the three samples, essential amino acids were high amounts, especially good taste component, glutamic acid was higher. 3. The mineral p Contents$(925\~115mg)$ were highest and Mg was higher amount, in hentinus edodes and Auricula-jude, K, Na, Ca, Cu, Zn, etc were identified, In Coriolus versicolor, K content was highest, on the other hand, Sequence of mineral amount was Ca, Fe and Na.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.8
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• pp.1038-1042
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• 2007

Stycla claca (SC, miduduk in Korean) and Stycla plicata (SP, omangdungi in Korean) have been consumed as one of the most tasty seafoods in the southern coast of Korea. Liquors were prepared by soaking SC (whole, tunic, or flesh part) and SP (whole) in soju (alcohol content 30%) for 4 months, and then the characteristics were evaluated. Alcohol contents of the liquors decreased with increasing amounts of SC and SP. Antioxidant activities revealed by a radical scavenging activity showed that SC, especially flesh part, exhibited higher activity than SP in the liquors. Increasing the amount of SC and SP in liquors tended to decrease lightness and redness while increasing yellowness. In a sensory test, there was no significant difference between the liquors.

• Food Science and Preservation
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• v.6 no.4
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• pp.463-468
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• 1999

The characteristics and quality of Yakju with addition of ginseng powder originated in Choongchungdo were evaluated. At result, pH was decreased at the beginning stage of two stages fermentation and then slowly increased. Total acidity were increased in the cases of all (A), (B) and (C) during the fermentation. (A) group used Nuruk, crude enzyme and powder yeast showed the highest pH of 7.08 and total acidity of 0.84 at the 4th day of fermentation. The alcohol contents of B(21.0%) and C(20.4%) used cultured yeast were higher than A(19.0%) used powder yeast at the 4th day of fermentation. Also, inhibition against alcohol fermentation by ginseng powder wasn't showed and amino nitrogen contents were higher in (A) and (C) with addition of crude enzyme. Free sugar were the highest in (A) used both Nuruk and crude enzyme such as glucose of 599.16, maltose of 129.11mg%. Free amino acids were much more in A(580.02mg%) than in B(527.48mg%) and C(538.74mg%). from the sensory evaluation, desirable color and flavor qulity for 40 ages was (A) and (B) which was used Nuruk, and that for 20 ages was (C) which was used crude enzyme. However the best taste and overall preference was (B) for 20 and 40 ages of all. Therefore to produce high quality Yauju and commercialize, studies of fermentation process in Yakju should proceed later.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.789-793
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• 1995

Chemical composition was determined to renew interest in acacia flower as food. The moisture content was 86.60%. The chemical composition showed 24.55% of protein, 8.51% of ash, 40.97% of total sugar and 160.44mg% of ascorbic acid on dry matter basis, respectively. Free sugar was mainly composed of fructose, sucrose and glucose. In fatty acid composition, the ratio of saturated and unsaturated fatty acids was 1.7 : 1. The unsaturated acids were primarily composed of polyenoic acid by more than 90%. The amino acid was distributed with a ratio 0.32 of essential to total amino acids. Important elements of acacia flower were K, Mg, Ca, Fe, and Na. Flavor components such as 24.19% of octadecanoic acid, 9.41% of benzyl alcohol, 7.05% of linalool, 5.43% of heptacosane and 4.28% of geraniol were identified as major volatile compounds of acacia flower.

• Korean Journal of Food Science and Technology
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• v.27 no.6
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• pp.964-971
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• 1995

Volatile flavor compounds and free amino acids in untreated and hydrolysate pen shell by-product produced with APL 440 protease were compared by vacuum simultaneous steam distillation-solvent extraction/gas chromatography/mass spectrometry. A total of 109 volatile flavor compounds were detected in hydrolysate (65 compounds) or the 109 volatile flavor compounds were detected in untreated pen shell by-product (88). These compounds were composed of aldehydes(16), ketones(17), alcohols(31), nitrogen containing compounds (16), aromatic hydrocarbon compounds(8), esters(3), and miscellaneous compounds (17). Levels of aldehydes and aromatic hydrocarbons decreased after hydrolysis, whereas levels of nitrogen containing compounds increased 3 times than in untreated pen shell by-product. Taurine, known to be having a physiological function, was accounted for 31.25% of total amino acids in hydrolysate.

• Korean Journal of Food Science and Technology
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• v.33 no.3
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• pp.353-360
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• 2001

Physicochemical characteristics of kochujang prepared with addition of garlic and onion, were investigated for 22 weeks of fermentation to obtain information on improving the quality of traditional kochujang. Moisture contents of kochujang increased during fermentation, but total nitrogen contents decreased slightly. The pH and titratable acidity of kochujang changed a little by addition of garlic or onion. Total sugar contents of kochujang decreased rapidly after 4 weeks, but reducing sugar contents increased until 2 weeks of fermentation. As the ratio of garlic increased, reducing sugar contents decreased. Ethanol contents increased during fermentation as mixing ratio of onion increased. Amino nitrogen contents of kochujang increased as mixing ratio of garlic or onion increased, but ammonia nitrogen contents decreased. Water activities of kochujang decreased slightly during fermentation, but consistency increased until 18 weeks. The color values of garlic or onion added kochujang were low in the L-values, but a- and b-values increased. Results of sensory evaluation showed garlic added$(2{\sim}4%)$ kochujang were more acceptable than onion added kochujang due to more favorable taste and flavor.

• The Korean Journal of Pesticide Science
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• v.10 no.1
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• pp.66-68
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• 2006

New synthetic method of 2-mercaptobenzoxazoles and 2-mercaptobenzimidazoles was established using elemental sulfur, dichloromethane, inorganic base and catalysts in alcohol solvents. This reaction condition gave products in high yields.

• Korean Journal of Food Science and Technology
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• v.52 no.5
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• pp.524-528
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• 2020

The aim of this study was to enhance the use of wheat bran in lactic acid bacteria (LAB) fermentation. LAB fermentation of wheat bran and the flavor components and amino acids of fermentation products were analyzed using gas chromatography-mass spectrometry (GC/MS) and high-performance liquid chromatography (HPLC). The results showed that total flavor components increased by 93% and 73% in the animal-based LAB mixture (T2) and plant-based LAB mixture (T3), respectively, after fermentation. Among these components, 2,3-butanedione (diacetyl), known for its buttery flavor, was detected at concentrations of 18.44 ng/g (T2) and 16.95 ng/g (T3). Levels of hexanal and nonanal, which causes off-flavor components in wheat bran, dramatically decreased after T2 fermentation; similarly, levels of total free amino acids decreased by 37.6% (T2) and 36.7% (T3) after fermentation. This may explain why some components were bound to volatile compounds during LAB fermentation. These results suggest that LAB-fermented wheat bran is a potential value-added food material.