• Korean Journal of Food Science and Technology
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• v.18 no.2
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• pp.118-123
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• 1986

Soy milk prepared from soy protein concentrate was fermented with Lactobacillus acidophilus, L. bulgaricus, L. casci, Streptococcus lactis or S. cremoris. Growth and acid production of each organism in soy milk and flavor of soy yogurt beverages were investigated. Volatile compounds in soy milk and soy yogurts were also determined. Among the five organisms tested, L. bulgaricus produced most amount of acid in soy milk while S. cremoris produced least amount of acid in soy mile. Sensory evaluation showed that the flavor of soy yogurt beverages was inferior to that of milk yogurt beverage and the flavor of soy yogurt beverage prepared by L. bulgaricus was better than that of other soy yogurt beverages. Soy milk fermented with L. bulgaricus was more acceptable than unfermented soy milk. Lactic fermentation reduced n-hexanal in soy milk while it produced diacetyl that was not detected in unfermented soy milk.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.3
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• pp.121-128
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• 1989

Volatile compounds were collected by simultaneous distillation extraction and carbon dioxide method, and analyzed by GC and GC-MS. The neutral fraction obtained from the whole steam volatile concentrate 55 kinds of components, phenolic fraction had 4 kinds of components, basic fraction had 13 kinds of components and 10 kinds of components were in acidic fraction. Alcohols, propanols, butanols, octanols, dodecanols etc. and aldehydes, pentanals, hexanal, 2-methyl-1-propanal, heptenal etc. were highly increased after boiled and roasted. And these compounds were contributed to formation of filefish flavor. The molecular ion peak of phenolic fraction was generally appeared in the range 100 to about 160. From the basic fraction, 2-methylpyrazine, 2,5-dimethylpyrazine, 2-ethyl-3,5-di-methylpyrazine and 2-methylpyridine were identified. The contents of basic compounds and furans obtained from the neutral fraction were increased at the higher heating temperature. The flavor of acidic fraction was influenced by the low molecular as isovaleric and valeric acid.

• Food Science and Preservation
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• v.10 no.1
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• pp.70-74
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• 2003

The distribution of mesophilic and thermophilic bacteria in milled rice was not different according to growing land and variety of rice. However, The number of these bacteria were abundant in milled rice of lower milling degree or longer storage period. The growth of thermophilic bacteria in cooked rice of electric rice cooker was rapidly increased during storage of lower temperature below 75 $^{\circ}C$. Thermophilic bacteria were not appeared just after cooking. After cooked rice was stored far 18∼24 hon thermophilic bacterial growth was rapidly increased by changing spore to vegetative cell. The positive relation between cell number of thermophilic bacteria and occurrence of off-odor was slightly observed. The number of thermophilic bacteria in upper cooked rice of oven and was higher than those in inner and lower cooked rice. Major volatile compound of milled rice cooked and stored in electric rice cooker was hexanal oriented from rice. After long storage, it was confirmed that furan was major volatile compound as off-odor.

• Food Science and Preservation
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• v.17 no.1
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• pp.151-159
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• 2010

Changes in volatile organic compounds were investigated during storage after electron beam irradiation. Grapes were irradiated at 0.25, 0.5, 0.75, and 1.0 kGy and stored for 1 month at $4^{\circ}C$. Butanol, hexanal, [E]-2-hexenal, hexanol, and 3-methyl-butanol were the major volatile organic compounds of grapes. The types of volatiles in irradiated grapes were similar to those of non-irradiated samples but concentration differed among treatments. Some volatile compounds decreased during storage, whereas others, especially the esters, increased. Concentration of most volatile compounds were higher in pre-stored grapes than in post-stored fruit (thus, during the 30 days after irradiation by e-beam). Consequently, concentration of volatile organic compounds either increased or decreased after e-beam irradiation but these changes did not correlate with irradiation dose.

• Applied Biological Chemistry
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• v.27 no.1
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• pp.14-20
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• 1984

Volatiles from Mallus pumila Miller Var. Fuji, Ralls Janet and Jonathan during maturity were examined. The volatiles of apples were collected by the headspace trapping method using. Tenax GC and identified by gas liquid chromatography and GC-mass spectrometry. Among over 34 GLC peaks, 23 esters, 9 alcohols and 2 aldehydes were identified. The quantity of volatiles produced was increased in proportion to the degree of maturity, and 1-butanol, isobutyl butyrate, 2-pentanol, ethyl valerate and hexanal were major.

• Journal of the Korean Society of Food Culture
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• v.20 no.2
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• pp.214-220
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• 2005

Seasoning oil (SO) for Chinese dish was manufactured from the combination of Maillard reaction for methionine and xylose with autoclaving method. Volatile compounds were determined by GC, GC-MSD for this SO and 3 kinds of seasoning jajang samples which was obtained from restaurant. From this SO 61 kinds-404.92ppm volatile compounds were separated and identified. And from 3 samples of restaurant, 39 kinds-333.52ppm, 42 kinds-330.01ppm, 42 kinds-393.18ppm obtained respectively. Major volatile components of SO were diallyl disulfide, pentane, diallyl trisulfide, t,t-2,4-decadienal and zinngiberene. Those contents were 40.15ppm, 32.32ppm, 19.57ppm, 15.06ppm and 13.23ppm, respectively. Major volatile components in 3 kinds samples were pentane, propenal, hexanal, t-2-heptanal, 2,4-heptadienal, t,t-2,4-decadienal and unknown components. The volatile components of SO were very similar to 3 samples,

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.342-347
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• 1999

Kiwifruit pulp was separated into insoluble pulp and serum by centrifugation at 14,000 rpm for 10 min. The serum portion was concentrated at $30{\sim}50mmHg\;and\;50{\sim}55^{\circ}C$ with aroma recovery. Vapor generated at the early stage of vacuum evaporation was condensed and taken as aroma fractions: $E-I\;(0{\sim}10%),\;E-II,\;(10{\sim}20%)$. The volatile flavor compounds in kiwifruit pulp were collected by dynamic headspace technique and analyzed by GC and GC/MSD. The yield of serum separated from kiwifruit pulp was 70.1% and insoluble pulp fraction contained aroma compounds more than that of the serum. Twenty-six aroma compounds, including (E)-2-hexanal and ethyl butanoate were detected. The efficiency of the aroma recovery was reduced as the recovery time was extended, as indicated by the less peak numbers and kiwifruit areas of aroma fractions.

• Journal of Life Science
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• v.20 no.3
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• pp.350-355
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• 2010

This study was carried out in order to characterize the flavor of Pueraria radix-green tea. To make a new tea with good flavor and functional properties, Pueraria radix was mixed with green tea. Volatile flavor compounds of Pueraria radix-green tea were extracted by simultaneous distillations and extraction methods using a Likens and Nickerson's extraction apparatus. The concentrated extract was analyzed and identified by GC and GC-MS. Forty-nine compounds including $\beta$-selinene, $\beta$-caryophyllene, hexanal and nonanal were isolated and identified from Pueraria radix. Sixty-four compounds including nerolidol, linalool, linalool oxide and phenylethyl alcohol were isolated and identified from green tea. Eighty-two compounds including linalool, $\delta$-cadinene, limonene, $\beta$-caryophyllene and $\beta$-ionone were isolated and identified from Pueraria radix-green tea.

• Food Science of Animal Resources
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• v.33 no.2
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• pp.214-220
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• 2013

The effects of different cations on its composition and flavor characteristics of pidan white and yolk produced with duck egg in comparison to its fresh egg were investigated. Mineral content such as calcium, magnesium, sodium and potassium were significantly increased in pidan yolk irrespective of its cations in pickle solution in comparison to the fresh yolk (P<0.05). It confirmed the migration of minerals from the pickling solution to the egg. However, calcium and magnesium was found lower in 0.2% $PbO_2$ treated pidan. Less pidan flavor compounds were generated in pidan white produced with the aid of 0.2% $PbO_2$. It confirmed that binding of lead prevent the maillard reaction in the pidan treated with $PbO_2$. Benzaldehyde, ketones, alcohol and acid found in the pidan white treated with 0.2% $ZnCl_2$ reveals that volatiles are generated most likely from maillard reaction. However, pidan yolk of both 0.2% $PbO_2$ and 0.2% $ZnCl_2$ showed higher generation of volatiles more likely from yolk lipids. Butanal, pentanal, hexanal, and heptanal are of those aldehydes found in 0.2% $ZnCl_2$ treated pidan yolk whereas hexanal is the only aldehyde detected in 0.2% $PbO_2$ treated pidan yolk. Thus, cations in the pickling solution affect the flavor characteristics of pidan white and yolk.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.770-774
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• 2002

Effect of surfactant micelles on lipid oxidation was determined in soybean oil-in-water (O/W) emulsions. The concentration of ferric irons to continuous phase in the O/W emulsions was measured as a function of various Brij type and concentrations. The concentration of ferric iron in the continuous phase increased with increasing surfactant micelles concentration $(0.5{\sim}2.0%)$ and storage time $(1{\sim}7\;days)$. At pH 3.0, the concentration of continuous phase iron was higher than at pH 7.0. Lipid oxidation rates, as determined by the formation of lipid hydroperoxides and headspace hexanal, in the O/W emulsions containing ferric iron decreased with increasing surfactant micelle concentration $(0.5{\sim}2.0%)$. These results indicate that surfactant micelles concentration could alter the physical location and prooxidant activity of iron in soybean O/W emulsions.