• Food Science and Preservation
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• v.18 no.5
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• pp.803-810
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• 2011

This study was performed to evaluate the quality of the commercial brown-rice vinegars of South Korean and Japanese origins, which were prepared via static acetic-acid fermentation. The major free amino acids of Korean brown-rice vinegars were proline, glutamic acid and phenylalanine, while those of the Japanese were proline, valine, phenylalanine, lysine, ${\gamma}$-aminobutyric acid, alanine and isoleucine. The ${\gamma}$-aminobutyric acid (GABA) and total amino acids (3686.37~4212.27 mg%) contents were found to be significantly higher in the Japanese than in the Korean brown-rice vinegars. The key volatile compounds of the Korean brown-rice vinegars, analyzed with GC-MS, were acetic acid, benzaldehyde, phenethyl alcohol and phenethyl acetate while those of the Japanese brown-rice vinegars were acetic acid, ethyl acetate, ethyl alcohol, isoamyl acetate, phenethyl acetate and benzaldehyde. The volatile patterns of the Korean and Japanese commercial brown-rice vinegars were effectively distinguished from each other using an electronic nose, through which it was also elucidated that the volatiles profiles were similar among the Japanese vinegars but were different among the Korean vinegars.

• Analytical Science and Technology
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• v.26 no.3
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• pp.199-204
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• 2013

In this study, the reproducibility of blood alcohol concentration (BAC) - time profile for the same individuals were investigated. Five Korean males were made to drink 55.5 g of ethyl alcohol (neglecting body weight) in the form of undiluted Soju (22% v/v), Korean popular liquor, within 30 min and each drinking sessions were performed for five times. Two kind of side dishes, a sliced raw fish and a sweet and sour pork, were served alternately along with alcohol. The peak BAC reaching time, the maximum BAC and the reduction rate of BAC of an individual varied greatly even though the dose and drinking time interval were not changed. Also, the food taken along with alcohol varies the shape of BAC - time profile. From the repetitive drinking sessions we can know that the BAC - time profile of an individual is not a reproducible one even though the dose, kind of liquer, drinking time and food were maintained constantly. It means that any assumption of blood alcohol concentration of an individual at a previous time stage based on the alcohol dose can not be justified because of large fluctuation of BAC-time profile of an individual.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1177-1179
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• 1996

A static headspace gas chromatographic (HSGC) technique was used to quantify toluene and other solvents (methanol, isopropyl alcohol, methyl ethyl ketone and ethyl acetate) in food packaging films. Comparison of retention times and coefficient variations for standard solvents showed consistent retention time and good reproducibility. Therefore, this method using static HSGC proved to be superior in rapidity and reproducibility, and is thought to be adaptable to analysis of a large number of samples. The methanol content was $N.D.\;(not\;detected){\sim}0.939\;mg/m^2$, toluene $N.D.{\sim}1.403\;mg/m^2$, melthyl ethyl ketone $N.D.{\sim}0.932\;mg/m^2$, total solvent content was $N.D.{\sim}2.433\;mg/m^2$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.956-963
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• 1995

Twenty esters, 14 alcohols, 5 aldehydes, 5 ketones, 5 lactones, 2 S-containing compounds and 1 hydrocarbon are identified by GC-MS from volatile compounds in a glucose solution containing Yeat-Carbon-Base medium fermented for 64 hrs by Saccharomyces bayanus at pH 3.5, $25^{\circ}C$, 400rpm and 35L/h of aeration for 24hrs. Under the different conditions of conservation(1~4), ethyl 2-hydroxy-4-metjhylpentanoate, ethyl succinate, nonanol and phenylacetaldehyde are produced during conservation of fermented solution. 17 esters increased during conservation at $13^{\circ}C$ for 12 weeks and the increase of ethyl 9-hexadecenoate is important among 13 esters increased during conservation at $35^{\circ}C$ for 24hrs. During conservation, aldehydes increased at $35^{\circ}C$, but decreased at $13^{\circ}C$ and the great increase of isobutanal, benzaldehyde and phenylacetaldehyde is observed at $35^{\circ}C$. Alcoho and lactones increased but ketones decreased during conservation.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1144-1150
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• 1997

Volatile flavor components of soybean koji kochujang made from a glutinuous rice by improved method were analyzed by using a purge and trap method during fermentation, and identified with GC-MSD. Fifty-six volatile flavor components including 16 alcohols, 15 esters, 7 acids, 4 aldehydes, 5 alkanes, 3 ketones, 1 benzene, 1 alkene, 2 phenol and 2 others were found in improved kochujang. The number of volatile flavor components detected immediately after making kochujang were 32 and increased to 46 components after 30 day of fermentation. The most number 55 of volatile flavor components were found after 90 day of fermentation. Thirty-one kinds of volatile flavor components were commonly found through the fermentation period 9 alcohols such as 2-methyl-1-propanol, ethanol, 3-methyl-1-butanol, 8 esters such as methyl acetate, ethyl acetate, 2-methylpropyl acetate, 3 aldehydes such as butanal, acetaldehyde, furfural and 11 othesrs. Although the various types of peak areas (%) of volatile flavor components were shown in kochujang during the fermentation days, ethanol. ethyl acetate, ethyl butanoate, 2-methylpropyl acetate, 2-methyl-1-propanol and 3-methyl-1-butanol were mainly detected during fermentation. Those might be the major volatile flavor components in kochujang made by improved method. Peak area of ethanol was the highest one among the volatile flavor components at immediately after mashing and 90 day while ethyl acetate showed the highest Peak area after $30{\sim}60$ day of fermentation and 3-methyl-1-butanol showed the highest peak area after $120{\sim}150$ day of fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.12
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• pp.2042-2048
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• 2013

This research was carried out to compare the physicochemical characteristics of Korean traditional spirits brewed with Phellinus linteus by different Nuruks. The spirits were produced by atmospheric distillation of rice mash added with 1~5% P. linteus and fermented by traditional and improved Nuruks. Traditional Nuruk facilitated more alcohol production than improved Nuruk during the initial fermentation time. The alcohol contents of rice mash with P. linteus ranged from 15.8 to 18.9%. Predominant volatile compounds were i-amyl alcohol of fusel oils and ethyl acetate of ester compounds in P. linteus added spirits. The spirits prepared by traditional Nuruk showed higher contents of i-butanol, n-butanol, and i-amyl alcohol than those by improved Nuruk. More ethyl acetate was produced in the spirits prepared by improved Nuruk than those by traditional Nuruk. The contents of methyl alcohol were less than 50 mg/L in P. linteus added spirits.

• Korean Journal of Food Science and Technology
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• v.17 no.1
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• pp.8-14
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• 1985

In order to give the unique flavour of traditional Doenjang (Korean-style soybean paste) to commercially manufactured soybean paste, the addition of Bacillus licheniformis and Saccharomyces rouxii was tried and their influences were investigated. The addition of B. licheniformis and S. rouxii in soybean paste decreased the content of reducing sugars. By the addition of B. licheniformis, the contents of amino type nitrogen and titrable acidity were increased. The content of ammoniacal nitrogen was reduced and ethyl alcohol production was increased by the addition of S. rouxii. The viable counts of molds showed the decreasing tendency during the aging and it was accelerated by the addition of B. licheniformis and S. rouxii. Acetaldehyde, acetone, ethylacetate, methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol and isopropyl alcohol were detected from the vapor of all tested ripen soybean pastes, while in a traditional Doenjang, isoamyl alcohol and isobutyl alcohol were not. The B. licheniformis and S. rouxii added sample showed richest free amino acid content. In organoleptic test the B. licheniformis and S. rouxii added sample showed the most excellent overall acceptability.

• Korean Journal of Food Science and Technology
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• v.24 no.3
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• pp.272-278
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• 1992

Takju, a Korean traditional wine, was prepared by using nuruk and Koji which were inoculated with Aspergillus kawachii and Aspergillus shirousamii. Those chemical composition such as alcohols and organic acids were determined with gas chromatography to investigate the variation of its content by the fermentation. Alcohol such as methyl, ethyl, n-propyl, i-butyl, i-amyl alcohol were detected in the most takju mash samples. Alcohol contents in the groups fermented with KNR and SNR were slightly higher than KKR, SKR groups. Lactic acid were concentrated and organic acids such as pyruvic, oxalic, malonic, succinic, maleic, malic, ${\alpha}-keto$ glutaric acid were also detected in the most samples. The pH was lowest in the KKR group. The total acid content was slightly decreased at the later fermentation and was highest in KKR. The content of minerals were highest in the WNR and BNR groups. Throughout fermentation the content of potassium and magnesium varied greatly with the tested groups.

• Polymer(Korea)
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• v.27 no.4
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• pp.358-363
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• 2003

Dispersion polymerization of acrylamide was carried out in the media of ethyl alcohol/water mixtures using hydroxypropyl cellulose and ammonium persulfate as steric stabilizer and initiator, respectively. The effects of concentrations of initiator and steric stabilizer, amount of monomer, polymerization temperature, ethyl alcohol/water ratio, and purification of monomer and nitrogen purge on the particle size of the latices and molecular weight of the polymers were investigated. The average particle diameter increased with increasing concentration of initiator, water content in ethyl alcohol/water media, and polymerization temperature, but decreased with monomer and stabilizer concentrations. The viscosity average molecular weight increased with increasing concentrations of monomer, steric stabilizer, and water content in dispersion media, but decreased with initiator concentration and polymerization temperature. The PAM polymers prepared with the purified monomer and the nitrogen purging before the reaction showed the highest molecular weight. In this study, PAM latices of 0.5∼2.4 $\mu\textrm{m}$ with 20000∼335000 in M$\_$v/ were prepared and the resulting PAM latices were all dissolved in water instantly.

• The Korean Journal of Physiology
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• v.2 no.1
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• pp.73-78
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• 1968

The changes of urinary excretion after alcohol drinking on 6 normal subjects sweated in a hot chamber were studied. The results are summarized as follows: 1. The urinary minute flow is increased rapidly to maximum about 60 minutes after intake of alcohol, and this is supposed to be originated from the antidiuretic suppressive action on osmoreceptor by ethyl alcohol. 2. Free water clearance and osmolarity of the urine showed the maximal and minimal values respectively at the sane time when the urinary flow is maximal. 3. The concentrations of Na, K and Cl were roughly proportionate to the urinary osmolarity and the minimal values after drinking were diluted to more than 10-fold than those before drinking, but the minute amounts of these ions is decreased only slightly during tile diuresis. 4. The concentrations of urea were decreased less than 10-fold but the minute amounts were rather increased slightly. 5. The diuresis could not excrete whole quantity of fluid intake in the period of 2 hours, and considerable amount of water was still retained in the body.