• Journal of the Korean Home Economics Association
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• v.25 no.1
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• pp.59-67
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• 1987

It these experiments, five kinds of Korean made coffee and three kind of foreign made coffee were analysed using gas chromatography after steam distillation. The results were as following: 1. In general the sample contained light aroma(carbohydrate derivatives), medium aroma(purin derivatives) and heavy aroma(furan dervatives). 2. More light aroma and medium aroma were found in freezing dried coffee than in spraying dried coffee. 3. Korean sample contained lignter aroma than that of foreign ones.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.3
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• pp.420-426
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• 1995

Volatile compounds in raw oyster and oyster hydrolysate produced with protease were compared by vacuum simultaneous steam distillation-solvent extraction/gas chromatography/mass spectrometry. Sixty-two volatile compounds were detected in both samples. Of these, 57 were positively identified, composed mainly of aldehydes(12), ketones(9), alcohols(14), nitrogen-containing compounds(9), acids(6), terpenes(4), and miscellneous compounds(8). Levels of acids decreased after hydrolysis, whereas several other compounds such as aldehydes, ketones, and nitrogen containing compounds increased. Pyrazines, found in high abundance, were only detected in oyster hydrolysate.

• Journal of the Korean Society of Tobacco Science
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• v.16 no.1
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• pp.20-25
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• 1994

The volatile components were extracted from root of Cnidium officinale M. by SDE(Simultaneous steam distillation and extraction) apparatus and analyzed by GC/M.5 and GC retention index matching. The experimental results revealed the presence of over 22 volatile components. Major components were cnidilide (35.1%), neocnidilids (13.4%), ligustilide (23.2%). The essential oils were separated by silica gel column chromatography(Merck 70-230mesh), and 4 fractions among 12 fractions separated had a, good aroma character.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2001.05a
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• pp.112-116
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• 2001

In the paper, desalination technology for a barge mounted plant is presented. Desalination system on a barge needs high efficiency, smaller space, and stability. Therfore 4-effect distillation system (capacity of 50ton/day) is designed and constructed. During operation, detailed investigation of different opereation parameters is carried. This paper discusses about product water flowrate and recover ratio with different steam flow rate and feed water rate.

• Journal of the Korean Society of Tobacco Science
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• v.6 no.1
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• pp.25-31
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• 1984

The volatile aroma components were isolated from Korean flue-cured tobacco (N.C. 2326) by using a vacuum steam distillation method. Individual aroma components were identified by GCIMS and comparison of gas chromatowaphic retention time with those of the authentic samples. Sensory analysis showed that a vacuum steam-distilled product of Flue-cured tobacco had a typical haylike, floral and fruity aroma. Among 62 compounds identified, major compounds included neophytadiene, benzyl alcohol, ethyl acetate, phenyl ethyl alcohol, ethyl alcohol, ethyl formate, acetic acid, solanone, 2-acetyl pyrrole, $\beta$-ionone epoxide, 2, 4-heptadienal (2 isomers), megastigmatrienone (4 isomers), furfural and total amounts of 13 compounds were about 80%.

• Korean journal of food and cookery science
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• v.1 no.1
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• pp.33-39
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• 1985

The volatile sulfur components from two varieties of radishes ('Taeback' and 'Altali'), obtained by steam distillation and solvent ($CCl_4$) extraction, were isolated and charac-terized by GC/MS analysis. The GC profile of the volatile sulfur com-pounds in the steam distillates from two types of radishes was quite similar. 4-Me-thylpentyl, 3-methylthiopropyl, 4-methylthio-3-butenyl, 4-methylthiobutyl and 5-methyl-thiopentyl isothiocyanates, 5-methylthio-4-pentenenitrile, 1-methylthio-3-pentanone, and dimethyl sulfides were commonly identified. In the $CCl_4$ extract, 4-methylsulfinyl-3-bu-tenyl isothiocyanate was obtained as another major constituent. Whereas 4-methylthiobutyl isothiocyanate was found to be a predominent component in the steam distillate, 4-methylthio-3-butenyl isothiocyananate was a major one in the $C1_4$ extract.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.4
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• pp.451-460
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• 2013

The purpose of this study is to investigate the volatile compounds of Korean traditional gochujang from various districts. The volatiles from each traditional gochujang are being extracted by simultaneous steam distillation extraction (SDE), and analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). Twenty compounds are identified as major volatile components which include 8 esters, 4 alcohols and 4 acids. The most traditional gochujang possesses more volatile components rather than commercial gochujang products. Most acids come from fatty acids and the alcohols derive from the oxidative degradation of linolenic acid. The most abundant volatile compounds for both traditional and commercial gochujang include 10 compounds such as 2-methyl-1-propanol, hexanal, 2-methyl-1-butanol, octanoic acid ethyl ester, as well as the various type of acids and esters. They represent most of the total GC peak areas, respectively. From the results, the characteristics of the flavors for traditional gochujang from each district are not clear but have shown various components than the commercial products.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.679-682
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• 1994

The volatile sulfur compounds in raw and dried garlic (Allium sativum L.) under various temperatures (50, 60, 70 and $80^{\circ}C$ ) were separated, identified by GC and GC/MS. In hexane extracts of raw garlic, 8 volatile sulfur compounds were identified and 11 compounds were identified in steam distillation extracts. The volatile sulfur compounds of raw and dried garlic were mostly composed of diallyl disulfide, diallyl trisulfide, allyl methyl trisulfide. According to the increase of drying temperature total amounts of volatile sulfur compounds in the hexane extracts decreased to $40{\sim}75$$, and in the steam distillation extracts decreased to $10{\sim}20%$. The amounts of diallyl disulfide, allyl methyl trisulfide decreased more than other volatile sulfur compounds, but diallyl trisulfide comparatively decreased lower.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.5
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• pp.513-522
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• 2013

In the present work, a numerical study of a horizontal falling film evaporator in a multi-effect distillation (MED) plant is performed. Tube bundles in the evaporator are described as porous media, and a volume-averaged method is applied. To calculate the fluid flow and phase change in the evaporator due to heat transfer in the system, FLUENT and user-defined functions (UDF) are used. To observe the performance of the evaporator under different operational conditions, tests are conducted for a steam mass flux ranging from 0.5 to 2.5 $kg/m^2s$ in the horizontal tube, for mass fraction of the noncondensable gas in the tube inlet ranging from 0% to 1%, and for film Reynolds numbers ranging from 100 to 1,000 for the falling film. The evaporation rate increases with the steam mass flux and Reynolds number. In contrast, the evaporation rate decreases by 0.87% with a 1% increase in the mass fraction of the noncondensable gas in the tube.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.822-827
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• 2007

The aroma characteristics and antioxidative activity of volatile compounds in heat-treated garlic (Allium sativum L.) were evaluated. The garlic was heated to various temperatures (100, 110, 120, and $130^{\circ}C$) for different lengths of time (1, 2, and 3 hr). The volatile compounds of heated garlic were extracted by simultaneous steam distillation extraction (SDE). Aroma compound profiles were analyzed by gas chromatography/mass spectrometry (GC/MS) and antioxidative activity was measured by 2,2-diphenyl-2-picrylhydrazyl (DPPH) assay and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) cation decolorization assay. The major aroma compounds were sulfur compounds such as dimethyl disulfide, 2-propen-1-ol, methyl-2-propenyl disulfide, dimethyl trisulfide, diallyl disulfide, methyl-2-propenyl trisulfide, and di-2-propenyl trisulfide. DPPH radical scavenging activity (EDA, %) and the ascorbic acid equivalent antioxidant activity (AEAC) of volatile compounds in heated garlic increased significantly with the increase of temperature and time (p<0.001). The EDA (%) and AEAC of raw garlic were 26.8%/10 mg garlic and 39.05 mg ascorbic acid equivalent per g sample. After heat treatment, the highest values were 40.50%/10 mg garlic for EDA (%) and 46.43 mg ascorbic acid equivalent per g sample for ABTS.