• 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.

• Korean journal of food and cookery science
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• v.2 no.2
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• pp.16-20
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• 1986

The major pungent component from Korean radish roots was purified by reverse phase high performance liquid chromatography (RPHPLC), and characterized as 4-methylthio-3-butenyl isothiocyanate on the basis of the sensory test (pungency), UV spectrum and mass spectrum analysis. The purified isothiocyanate moved as a single peak(retention time, 5.2 min) in RP-HPLC analysis, and as a single spot(Rf, 0.9) in TLC analysis.

• Korean Journal of Food Science and Technology
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• v.18 no.6
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• pp.475-478
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• 1986

RP-HPLC (Reverse phase-high performance liquid chromatography) assay which was introduced to measure quantitatively the amount of 4-methylthio-3-butenyl isothiocyanate in the radish root, proved to be convenient, accurate and reproducible, showing a good linearity between 10 n moles/ml and 120 n moles/ml (r=0.9997). The results of this assay showed that while the isohtiocyanate was hydrolyzed slowly in the basic medium, it decomposed rapidly in the acidic aqueous medium. On the other hand, the isothiocyanate was relatively stable in the organic solvent (65% acetonitrile). Also, it was found that intact root of Korean radish contain 210-420 ${\mu}moles/100g$, based on the measurement with radish homogenate (pH 8.5, 1 min).

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.3
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• pp.315-319
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• 2003

Bioactive organosulfur phytochemicals were isolated from fresh broccoli using methlylene chloride as an extract solvent and identified by GC/MSD analyses. Major organosulfur phytochemicals of broccoli extract were found to be isothiocyanates, which constitute 40.42% of total phytochemicals. The isothiocyanates from broccoli extract were identified to be 3-butenyl, 4-methyl thiobutyl, 4-methylthio-3-butenyl, 5-methylthiopentyl, 2-phenylethyl, 3-methyl sulfinyl propyl, and 4-methylsulfinylbutyl isothiocyanates, of which major isothio cyanates were 3 butenyl isothiocyanate and 4-methylsulfinylbutyl isothiocyanate, constituting about 38.55% of total isothiocyanates present in the solvent extract. Also, nitrites, corresponding to products from enzymatic hydrolysis of glucosinolates were identified as 4-methylthiobutyl, 5-methyl thiopentyl, 2-phenylethyl and 4-methylsulfinylbutyl nitrile. In addition, three sulfides were identified as dimethyl disulfide, dimethyl trisulfide and dimethyl tetrasulfide.

• Korean Journal of Food Science and Technology
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• v.24 no.4
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• pp.361-366
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• 1992

Studies were carried out on the factors responsible for the change of pungency in 'Kagdugi'. During fermentation, the pH in 'Kagdugi' decreased to around to 4, while acidity increased continuously. In accordance with the decrease of pungency, the content of 4-methylthio-3-butenyl isothiocyanate (MTB-NCS) in the homogenate of 'Kagdugi' decreased gradually and on 3rd day, the optimum period for good flavor, below 5% of that in the homogenate of fresh radish. The decrease of MTB-NCS formation was accompanied by the gradual loss of 4-methylthio-3-butenyl glucosinolate (MTB-glucosinolate), which was found to disappear more rapidly than total glucosinolate. Also, the ascorbic acid-dependent myrosinase activity was observed to decline gradually with the fermentation time, although the ascorbic acid content varied above the concentration required for maximal enzyme activity. Thus, it was suggested that the decline of MTB-NCS may be related to the gradual losses of MTB-glucosinolate content and myrosinase activity which are both susceptible to the effect of acidic pH.

• The Korean Journal of Food And Nutrition
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• v.14 no.1
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• pp.20-27
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• 2001

The consumption of radish ( Rhaphanus sativus L.) sprout, which is Cruciferae family, is increasing because of its pungent flavor and taste. Its volatile components were analyzed by SDE (simultaneous steam distillation & extraction) method and P&T(purge & cryogenic trapping) method. As a solvent, diethyl ether and diethyl ether : pentane mixture(2:1, v/v) were used in SDE method, and diethyl ether in P&T method. Analyzing by GC and GC-MS, the major component was sulfur compounds (19 species, peak area 76.6%) with diethyl ether, sulfur compounds(15. 44.0%) and hydrocarbons(23, 23.8%) with diethyl ether-pentane mixture in SDE method. Also, hydrocarbons(25, 84.1% ) was major component in P& T method. The major volatile component of fresh radish sprout were n-heptane, methyl pentane and that of boiled radish sprout were 4-methylthio-3-butenyl isothiocyanate, methyl mercaptane, 2,3-dimethyl disulfide. Low molecular volatile components were detected more by P& T method, but types and relative quantities of volatile components were measured less comparing to SDE method.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.6
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• pp.1201-1207
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• 1999

To utilize the leaves of broccoli, the shape of which was similar with that of kale leaves, as a vegetable juice, the extracts from two types of vegetable leaves were subjected to the analyses of proximate com ponents, volatile sulfur compounds, vitamin C and minerals. The sensory evaluation of the juices, prepared from kale and broccoli leaves, were performed by duo trio test and scoring test. Among eight varieties of broccoli, four varieties('Pilgrim', 'Greenbelt', 'Salinas' and 'Shasta')were not significantly different from kale(p<0.05), based on the duo trio sensory test. Sulfur and nitrogen compounds present in the dichloromethane extracts of kale and broccoli leaves 'Pilgrim' were identified as 3 butenyl, allyl, butyl and 4 methylsulfinylbutyl isothiocyanate(sulforaphane), 4,5 epithiovalero, 4,5 epithio 3 hydroxyvalero, benzenepropane, 3 hydroxy 4 propene, 4 methylthio butane, 3 hydroxy 3 phenylpropane, 5 methy lsulfinylpentane, 4 methoxyphenyl 3 hydroxypropane nitrile and dimethyl trisulfide by GC/MSD analysis. Proximate components were observed to be relatively similar between kale and broccoli leaves. Vitamin C and sugar content were higher in broccoli leaves(125∼180mg% and 8∼12°Brix) than in kale(101mg% and 7oBrix). In mineral analysis by AA and ICP Mass, 'Pilgrim' showed a higher content of K, Fe, Mn, Zn and Se. In separate experiment, sensory scores of bitter taste and astringent taste were lower and scores of over all taste and over all acceptability, higher in broccoli('1243') juice than those in kale juice.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.762-771
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• 1996

Chemical and sensory characteristics of kakdugi which was prepared with various radish cultivars and harvesting seasons were analyzed during 7-day storage. Average pH of small radish cultivar kakdugi was higher than that of large ones, and total acidity was lower in small ones. Reducing sugar content was the highest in kakdugi of autumn radish. Organic acids such as lactic, succinic and fumaric acid analyzed by GC increased until the third day of fermentation, whereas volatile isothiocyanates analyzed by GC/MS continued to decline. There was a significant difference in flavor characteristics of large radish kakdugi across seasons, in contrast to no significant difference in those of small radish kakdugi except sweet taste and reducing sugar content in which interaction existed between season and cultivar. Score of overall acceptability was higher in small radish than large ones with Dongja showing the highest score of overall acceptability. Overall acceptability of autumn Dongja kakdugi was positively correlated with radish kakdugi odor and sour odor, respectively, but negatively with total acidity, lactic acid content, sweet taste and pungency, respectively. By multiple regression analysis, overall acceptability in spring Dongja kakdugi is expressed as a function of overall acceptability = -0.1115 + 1.2519 savory taste + 1.5159 malic acid -0.0054 total isothiocyanate + ${\varepsilon}$.