• 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.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.6
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• pp.731-739
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• 2006

The text of 'Jeungbosallimgyeongjae' was reviewed to study the manufacture of vinegar and to investigate the changes made to the manufacturing process over time, other works such as 'Eumsigdimibang(1670s)', 'Sallimgyeongjae(1715)', 'Gyuhapchongseo(1815)', 'Juchan(1800년대경)' and 'Chosun-mussangsinsikyorijaebeop(1930)', 'Chosun-eumsikmandeneubeop(1946)' were compared. In both 'Eumsigdimibang', and 'Sallimgyeongjae' there are only three statements on vinegar manufacturing theory. For 'Sallimgyeongjae' these statesments are recorded specifically in the 'Chison' section. This book contains the following topics: the proper number of days for vinegar fermentation vinegar storage theory, how to maintain the vinegar in the pot, and nine vinegar manufacturing theories. 'Gyuhapchongseo' discusses the proper or improper number of days to ferment vinegar, and offers four general theories on vinegar manufacture. 'Ju-Chan' is a book of recipes from the latter era of the Chosun Dynasty. There are three statesments on 'yangchobang' recorded in this book. 'Chosun-mussangsinsikyorijaebeop' contains a general summary on vinegar that includes the theory of vinegar production, the right number of days for fermenting vinegar, clues for maintaining the vinegar in the pot, the method for making vinegar from spoiled alcohol, and finally, how to keep vinegar from molding The book also includes 11 statesments on the theory of vinegar manufacture. In 'Chosun-eumsikmandeneubeop', there are two statesments on vinegar manufacturing theory recorded. To study the use of vinegar in cooking as well as the change in manufacturing theories over time, we selected 'Eumsigdimibang', 'Sallimgyeongjae', 'Gyuhapchongseo', 'Chosun-mussangsinsikyorijaebeop' for a comparative analysis with the book 'Jeungbosallimgyeongje'. From this comparison of the texts we were able to learn the scientific nature of traditional foods. In addition, current vinegar manufacturing practices are changing the originally enjoyed flavors ghat are found with traditional vinegars. By the investigation of historic recipe book 'Ju-Chan,' and given the regular use of vinegar on cooking, we have found the means to reproduce the relished tastes of the past.

• Journal of Applied Biological Chemistry
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• v.52 no.3
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• pp.93-102
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• 2009

Polyunsaturated fatty acids (PUFA), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have significantly beneficial effects on health in relation to cardiovascular, immune, and inflammatory conditions and they are involved in determining the biophysical properties of membranes as well as being precursors for signaling molecules. PUFA biosynthesis is catalyzed by sequential desaturation and fatty acyl elongation reactions. This aerobic biosynthetic pathway was thought to be taxonomically conserved, but an alternative anaerobic pathway for the biosynthesis of PUFA is now known to contain analogous polyketide synthases (PKS). Certain fish oil can be a rich source of PUFA although processed marine oil is generally undesirable as food ingredients because of the associated objectionable flavors that are difficult and cost-prohibitive to remove. Oil-seed plants contain only the 18-carbon polyunsaturated fatty acid alpha-linolenic acid, which is not converted in the human body to EPA and DHA. It is now possible to engineer common oilseeds which can produce EPA and DHA and this has been the focus of a number of academic and industrial research groups. Recent advances and future prospects in the production of EPA and DHA in oilseed crops are discussed here.

• Journal of Food Hygiene and Safety
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• v.23 no.2
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• pp.91-97
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• 2008

Kimchi is a representative traditional food in Korea and a type of vegetable product that is the unique complex lactic acid fermentation in the world. It can be considered as a unique fermented food generated by various flavors, which are not included in raw materials, that can be generated by mixing and fermenting various spices and seasonings, such as red pepper powder, garlic, ginger, and salted fish, added to Chinese cabbages. Functionalities in Kimchi have been approved through several studies and the probiotic function that is mainly based on lactic acid bacteria including their physical functions in its contents has also verified. Studies on the verification of the safety of Kimchi including its physiological functions have been conducted. In particular, the function of lactic acid bacteria, which is a caused of the fermentation of Kimchi. Although the lactic acid bacteria contributed to the fermentation of Kimchi is generated from raw and sub-materials, the lactic acid bacteria attached on Chinese cabbages has a major role in the process in which the fermentation temperature and dominant bacteria are also related to the process. The salt used in a salt pickling process inhibits the growth of the putrefactive and food poisoning bacteria included in the fermentation process of Kimchi and of other bacteria except for such lactic acid bacteria due to the lactic acid and several antimicrobial substances generated in the fermentation process, such as bacteriocin and hydrogen peroxide. In addition, the carbon dioxide gas caused by heterolactic acid bacteria contributes to the inhibition of aerobic bacteria. Furthermore, special ingredients included in sub-materials, such as garlic, ginger, and red pepper powder, contribute to the inhibition of putrefactive and food poisoning bacteria. The induction of the change in the intestinal bacteria as taking Kimchi have already verified. In conclusion, Kimchi has been approved as a safety food due to the fact that the inhibition of food poisoning bacteria occurs in the fermentation process of Kimchi and the extinction of such bacteria.

• Journal of the Korean Society of Food Culture
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• v.27 no.6
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• pp.659-665
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• 2012

This study investigated the effect of salt preference on dietary habits and the body composition of university students. The subjects were divided into two groups: 85 students who dislike salt (salt-dislike (SD) group) and 104 students who like salt (salt-like (SL) group). We found that the SL group showed a higher preference for sweet, sour, spicy, and bitter flavors compared to the SD group. There was no significant difference in the frequency of eating breakfast according to the salt taste preference. The meal speed of the SL group was significantly higher than the SD group (p<0.01) and the body mass index of the SL group ($22.59kg/m^2$) was higher than SD group ($21.04kg/m^2$). The fat mass of the SL group (15.30 kg) was higher than the SD group (12.80 kg) (p<0.01). Salt preference and snack intake frequency had a significant and positive correlation with fat mass. The frequency of eating breakfast, and meal speed also showed a significant and positive correlation with subcutaneous fat. In conclusion, the SL group eats relatively more, speedily and frequently intakes snacks and carbonated drinks, likely resulting in higher body and subcutaneous fat. These results suggest salt preference is related to food choice, influences unreasonable eating habits, and possibly changes body composition. Taste preferences should therefore be considered for dietary consulting and nutritional education.

• The Korean Journal of Food And Nutrition
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• v.25 no.4
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• pp.1008-1015
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• 2012

Sulgidduk is a kind of basic steamed rice cake in Korea. Multifunctional portable grinder was used for making sulgidduk and investigated the characteristic changes of rice powder for deciding the proper particle size of rice powder. Operation times for grinding the water absorbed swelled rice were 10, 20, 30 and 40 seconds. Moisture contents of rice powder and sulgidduk showed an increasing tendency with an increase of operation times for grinding. Springiness showed significant differences according to the operation times. Cohesiveness was decreased severely after 40 seconds grinding. Chewiness showed high after 20 seconds grinding in all groups; however, decreased after 40 seconds grinding and showed similar chewiness of the control group. Fracturability also showed severe increased tendency after 20 seconds grinding and decreased after 30 seconds grinding. Strength and hardness showed significant differences; they were increased until 30 seconds and severely decreased after 40 seconds grinding. L values showed significant differences in all the groups ($p{\leq}0.05$). The a and b values did not show any differences in all groups. Overall sensory evaluations, such as colors, flavors and texture, were increased with operation times for grinding and showed significant differences among the groups (p<0.05). As a result of this study, 40 seconds grinding times were the best condition for making sulgidduk, using by multifunctional grinder.

• The Korean Journal of Food And Nutrition
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• v.25 no.4
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• pp.903-910
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• 2012

This study was conducted to examine the applicability of muffins and the optimal ratio of batter mixture by adding mugwort with various functions and physiological active substances. In result of examining the quality characteristics of muffins after adding frozen-dried mugwort powder by 0%, 1%, 3%, 5%, or 7%, the moisture retaining capacity of muffin batter was lowest with MPM0, the control group, and the deposition was highest at $17.94m{\ell}$ with MPM0. The pH value of muffin batter was highest at 8.62 with MPM0 and moisture decreased significantly (p<0.001) when more mugwort powder was added to the sample. The brightness increased significantly (p<0.001) when the amount of frozen-dried mugwort powder decreased and redness and yellowness decreased when the addition of mugwort powder increased. The height and volume of mugwort muffins were lowest at 4.75 cm and $135.69m{\ell}$ with MPM7 with the greatest value of frozen-dried mugwort powder. The loss at baking of mugwort muffins was lowest at 2.27% with MPM7. The hardness of mugwort muffins was highest with MPM7 with the highest mugwort powder content. Coagulation and resilience was highest at 0.64 with the MPM0 control group and the chewiness increased significantly (p<0.001) with greater amount of frozen-dried mugwort powder. The appearance of mugwort muffins was highest at 6.1 with MPM5 and the most preferable color and flavors were found with MPM3. Tenderness was highest with the MPM0 control group. Overall preferability was highest with MPM3 with 3% frozen-dried mugwort powder. When adding frozen-dried mugwort powder to muffins, the 3% and control groups mostly showed the highest values, whereas the 5% group and higher groups showed lower values.

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.443-448
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• 2005

Isoflavone content of soymilk prepared with germinated soybean significantly increased. Soymilk prepared with Shinpaldal-2 germinated far 12 hr showed maximum 5.552 mg/g isoflavone. Solid content in soymilk increased from 5.68 to 6.02% for Shinpaldal-2 and from 5.30 to 6.10% for Seomoktae with 24 hr germination. 'L' values of soymilk increased, whereas 'a' and 'b' values decreased. Viscosity of soymilk decreased, while stability increased as germination time increased up to 24 hr, Organoleptic flavor properties of soymilk improved, showing decrease in benny and increase in savory flavors. Acceptance test showed soymilk prepared with 12 hr germinated Shinpaldal-2 showed highest acceptance, while Seomoktae soymilk showed least.

• Korean Journal of Microbiology
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• v.49 no.3
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• pp.286-291
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• 2013

Soybean pastes with 8% (w/w) salinity were prepared instead of soybean paste with 14% (w/w) salinity to meet the growing demands of Korean's low sodium diet. After aging, white films had appeared on the surface of all low-salted soybean pastes [8% (w/w) salinity] unlike high-salted soybean pastes [14% (w/w) salinity]. All of eight microbes isolated from the surface film were identified as Pichia kudriavzevii. Eleven Bacillus strains with good characteristics of fermentation were isolated from traditionally fermented soybean pastes in order to preserve their unique flavors and aromas after aging, and as a result of analyzing the biochemical characteristics and 16S rRNA sequences, those were identified as B. subtilis, B. licheniformis, and B. methylotrophicus. All of the Bacillus isolates had antagonistic activities against 8 isolates of the film-forming yeasts and harbored the genes for synthesis of antimicrobial surfactants including lichenysin and/or surfactin.

• Journal of Microbiology and Biotechnology
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• v.20 no.4
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• pp.767-774
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• 2010

In this study, the problems of high caloric content, increased maturation time, and off-flavors in commercial beer manufacture arising from residual sugar, diacetyl, and acetaldehyde levels were addressed. A recombinant industrial brewing yeast strain (TQ1) was generated from T1 [Lipomyces starkeyi dextranase gene (LSD1) introduced, ${\alpha}$-acetohydroxyacid synthase gene (ILV2) disrupted] by introducing Saccharomyces cerevisiae glucoamylase (SGA1) and a strong promoter (PGK1), while disrupting the gene coding alcohol dehydrogenase (ADH2). The highest glucoamylase activity for TQ1 was 93.26 U/ml compared with host strain T1 (12.36 U/ml) and wild-type industrial yeast strain YSF5 (10.39 U/ml), respectively. European Brewery Convention (EBC) tube fermentation tests comparing the fermentation broths of TQ1 with T1 and YSF5 showed that the real extracts were reduced by 15.79% and 22.47%; the main residual maltotriose concentrations were reduced by 13.75% and 18.82%; the caloric contents were reduced by 27.18 and 35.39 calories per 12 oz. Owing to the disruption of the ADH2 gene in TQ1, the off-flavor acetaldehyde concentrations in the fermentation broth were 9.43% and 13.28%, respectively, lower than that of T1 and YSF5. No heterologous DNA sequences or drug resistance genes were introduced into TQ1. Hence, the gene manipulations in this work properly solved the addressed problems in commercial beer manufacture.