• Microbiology and Biotechnology Letters
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• v.34 no.3
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• pp.244-249
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• 2006

In order to select the best strains to have the feasibility of Cheonghju brewing, 10 wild type yeast strains from 300 different types of Nuruk were investigated on their ethanol resistance, resistance to glucose and flocculation. The amounts of alcohol, organic acids, and volatile compounds, Brix, pH were also examined for the alcoholic beverages made with the 10 selected strains. Almost all strains showed alcohol production activities in the medium containing 18%(v/v) ethanol and 29%(w/v) glucose. The strains 90-2 showed a higher flocculation activity than other strains. Strains 54-3, 90-2 and 91-5 produced more alcohol than control strain (7.42%(w/w)) when fermented with wild type yeast strains. In addition, alcoholic beverages containing low acetic acid also showed low levels of total acidity. GC/MS analysis of the product showed 4 alcohols, 11 esters and 1 acid as volatile compounds. Selected strains were tentatively identified as Phichia sydowiorum (91-5), Zygosaccharomyces cidri (192-2 and 271-4), and as Saccharomyces cerevisiae (18-2, 54-3, 90-2, 91-2, 98-2, 99-5 and 272-7) by BIIOLOG method.

• Food Science and Preservation
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• v.23 no.1
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• pp.117-126
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• 2016

This study was performed to provide information for improving the quality characteristics of tangerine peel Soksungjang. Tangerine peel Soksungjangs were prepared with 10% tangerine peel powder by addition of different koji such as Rhizopus oligosporus (RS, RTS) and Aspergillus oryzae (AS, ATS). As a result, the moisture content was not changed and crude protein content decreased during fermentation in all samples. The pH of RS (Soksungjang manufactured with Rhizopus oligosporus koji) and RTS (Soksungjang manufactured with Rhizopus oligosporus koji and 10% tangerine peel powder) was not changed, whereas pH of AS (Soksungjang manufactured with Aspergillus oryzae) and ATS (Soksungjang manufactured with Aspergillus oryzae koji and 10% tangerine peel powder) decreased rapidly after 10 days of fermentation. The acidity values of all the samples increased during fermentation. The major free sugars were glucose, fructose, and maltose; while, the major organic acids were citric acid, succinic acid, acetic acid, and lactic acid in all the samples. The amino nitrogen content and protease activity were highest in the AS and ATS. Conversely, the reducing sugar content and ${\alpha}$-amylase activity were highest in the RS and RTS. The major free amino acids in all samples were glutamic acid, lysine, leucine, and arginine. Sixty kinds of volatile flavor compounds were identified from all samples; the majority of which were 21 alcohols, 14 hydrocarbons, 5 esters, and others identifies as acids, ketones, and aldehydes.

• Clean Technology
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• v.18 no.2
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• pp.191-199
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• 2012

In order to reduce or remove off-flavor and volatile organic compounds (VOCs) from Laminaria japonica effectively, continuous treatment process by supercritical carbon dioxide (SC-$CO_2$) was applied. After freeze-drying, Laminaria japonica powdered with $710{\mu}m$ was used. Experiments were carried out at temperature range from 35 to $55^{\circ}C$, and pressure range from 10 to 25 MPa for evaluation of SC-$CO_2$ treatment effect. Flow rate of carbon dioxide used in this reseach was constantly fixed at 26.81 g/min. Before and after treatment of SC-$CO_2$, off-flavor and VOCs from Laminaria japonica were analyzed by gas chromatography-mass spectrometry detector (GC-MSD). Total 47 VOCs emitted from Laminaria japonica were identified before treatment of SC-$CO_2$, major components of seaweed smell (ordor) in Laminaria japonica were identified as alcohols, aldehydes, ester and acids, ketone, halogenated compounds and hydrocarbon. Off-flavor and VOCs in all experimental conditions was reduced or removed after SC-$CO_2$ treatment. Among the experimental conditions, the highest removal yield was at 25 MPa and $55^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.36-44
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• 1999

Samjangs which were prepared using magjang, traditional doenjang, and mixture of traditional doenjang and magjang were stored. Characteristics of the stored samjangs were investigated. Maximum titratable acidity was shown in traditional doenjang after 30 day of storage. Total sugar in samjangs decreased while reducing sugar increased to $11.45{\sim}12.35%$ from $8.44{\sim}9.29%$ after 40 days. Amino type nitrogen predominantly increased to $337.3{\sim}381.1\;mg%$ after 40 days from $48{\sim}53\;mg%$ of initial period of preparation. Among the free amino acids the content of glutamic acid $(202.6{\sim}464.6\;mg/100g)$ was highest and others were not too much changed. Forty two components including 7 alcohols, 4 esters, 13 acids, 6 aldehydes, 5 phenols, 3 pyrazines and others were found in samjangs. Ethanol, acetic acid ethyl ester and 2-phenylethanol were found in all treatments and ethanol, acetic acid ethyl ester, phenylacetaldehyde, butanoic acid, acetic acid, 3-methyl butanoic acid and 2,4-hexadienoic acid might be major volatile components considering of high peak area. 2-Phenylethanol, butandioic acid ethyl ester, butanoic acid and 2-methyl-2-butenoic acid were higher than other components in samjang with magjang while ethanol, acetic acid, 2,4-hexadienoic acid were in samjang with traditional doenjang and 3-methyl butanoic acid, acetic acid ethyl ester and methyl pentanoic acid were in the mixed treatment.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.154-163
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• 2005

Chemical and flavor components of Bulro Kugi (Lycium chinense Mill) fruit leaf, and root were compared. Fructose and glucose were detected in fruit and leaf, and sucrose in root, respectively. Citrate was the highest among organic acids in fruits, and malate in leaf and root Capsaicin was detected in leaf and root. Volatile flavor compounds were extracted by simultaneous distillation and extraction method using Likens and Nickerson's extraction apparatus. Concentrated flavor extract was analysed, and 128 compounds, including 22 acids 15 alcohols, 12 aldehydes, 8 esters, 10 furans, 26 hydrocarbons, 4 phenols, 2 pyrroles, 1 pyrazine, and 28 miscellaneous components. were identified by GC and GC-MS. Main volatile compounds were hexadecanoic acid and 2-furancarboxaldehyde in hot-air dried fruit, hexadecanoic acid and 1-hexadecene in fresh fruit, 3, 7, 11, 15-tetranethyl-2-hexadecan-1-ol and hexadecanoir acid in leaf, and hexadecanoic acid in root.

• KSBB Journal
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• v.21 no.6 s.101
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• pp.405-409
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• 2006

Bokbunja (Rubus coreanus Miquel) is a wild berry belonging to Rosaceae genus of which application areas have been expanded due to many health effects. Bokbunja berry contains carbohydrates, protein, fats and dietary fibers as major components and various flavonoids such as tannins, volatile components including organic acids, alcohols and hydrocarbons as minor ones. Those active compounds attribute to the following health effects: increase in immune function and antioxidant activity, rise in hormone secretion, suppression of the growth of type B hepatitis virus, and control of weight gain. To utilize the above activities, many products have been developed by using Bokbunja berry extracts in the area of foods, liquors, and cosmetics. Recently, pure compounds have been isolated from the extracts for the development of medicines. In this mini review, the state-of-the-art of Bokbunja researches and applications including papers and patents is summarized.

• The Korean Journal of Food And Nutrition
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• v.31 no.5
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• pp.703-711
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• 2018

This study was carried out to investigate quality characteristics of Korean domestic commercial meoru wines, 8 kinds of wines were purchased from the Korea Wine Festival in 2016 and we compared the characteristics and physiological activity of 8 domestic wine. The results of this study have shown that the alcohol contents of wines ranged from 9.8 to 14.3%, pH of wines ranged from 3.86 to 4.22 and the total acidity of wines ranged from 0.56~0.75%. The hue value of meoru wines ranged from 0.81 to 1.02, The brightness of meoru wines ranged from 0.77 to 5.55, the redness from 3.97 to 31.16, and the yellowness from 0.99 to 5.63. The organic acid analysis of wine revealed lactic acid content at 4.281~9.606 mg/mL, followed by malic acid, tartaric acid, and acetic acid. The concentrations of total polyphenol and anthocyanin contents in the samples were investigated by spectrophotometric methods. Total polyphenol contents of the M8 (172.24 mg%) wine was higher than those of the other wines and total anthocyanin contents represented from 356.69 to 601.33 mg/mL. The DPPH radical scavenging activity of meoru wines was between 57.23 to 73.98%. Volatile flavor component analysis of meoru wines identified 7 alcohols, 16 esters, 5 acids, 3 terpenes and 4 other compounds.

• The Korean Journal of Food And Nutrition
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• v.33 no.3
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• pp.279-286
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• 2020

In this study, the properties of the substances fermented soybean producted by manufacturing with several Aspergillus strains were investigated. The five soybean cultivar that includes miso, jinpung, pyeongwon, cheonga and chamol were used in this experiment. The pH and total acidity were 6.30~6.66%, and 0.27~0.48%, respectively with differences depending on the samples. The color values for L value, a, and b value were 60.28~69.80, 0.64~3.68, and 11.48~31.21, respectively. The amylase activities, protease activities, and amino-type nitrogen of the jinpung samples were the highest among all cultivars. The mold counts the fermented soybean products by cultivars were 6.18~9.14 log CFU/g, and miso was the highest. Free amino acid and organic acid contents were highest in the jinpung and showed different composition depending on each sample. A total of 18 volatile aroma-compounds, including two acids, four alcohols, four ketones, three phenols, one furan, three pyrazines, and one miscellaneous compounds. In conclusion, it is expected that manufacturing A. oligze inoculation fermented soybean products using jinpung cultivar will improve quality.

• Journal of Microbiology and Biotechnology
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• v.28 no.8
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• pp.1260-1269
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• 2018

Production of good Koji primarily depends upon the selection of substrate materials and fermentative microflora, which together influence the characteristic flavor and aroma. Herein, we performed comparative metabolomic analyses of volatile organic compounds (VOCs) and primary metabolites for Koji samples fermented individually with Bacillus amyloliquefaciens and Aspergillus oryzae. The VOCs and primary metabolites were analyzed using headspace solid phase microextraction (HS-SPME) followed by gas chromatography time-of-flight mass spectrometry (GC-TOF-MS). In particular, alcohols, ketones, and furans were mainly detected in Bacillus-fermented Koji (Bacillus Koji, BK), potentially due to the increased levels of lipid oxidation. A cheesy and rancid flavor was characteristic of Bacillus Koji, which is attributable to high content of typical 'off-flavor' compounds. Furthermore, the umami taste engendered by 2-methoxyphenol, (E,E)-2,4-decadienal, and glutamic acid was primarily detected in Bacillus Koji. Alternatively, malty flavor compounds (2-methylpropanal, 2-methylbutanal, 3-methylbutanal) and sweet flavor compounds (monosaccharides and maltol) were relatively abundant in Aspergillus-fermented Koji (Aspergillus Koji, AK). Hence, we argue that the VOC profile of Koji is largely determined by the rational choice of inocula, which modifies the primary metabolomes in Koji substrates, potentially shaping its volatolome as well as the aroma characteristics.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.202-210
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• 2004

Doenjang, traditional Korean soybean paste without soysauce and soondoenjang that was not isolated soysauce from soybean paste were thermally processed by the addition of dry anchovy, garlic, red pepper powder and green onion. The volatile flavor components generated from doenjang soup and soondoenjang soup were studied and compared with the change in the various flavors. It was confirmed that some difference of the flavor components was found in two type of soups. Doenjang soup contained a plenty of aldehydes and ketones that revealed the savory flavor. The major flavor components in the soondoenjang soup were sulfur containing compounds that appeared the highest ratio than any other types of flavors and 10 pyrazines. On the sensory evaluation, a great number of pyrazins may be considered as a characteristic of the savory flavor of soondoenjang soup, however, it was not give the reliable result. Stepwise multiple regression analysis of two type of soups indicated that aldehydes, alcohols, ketones were contributory flavor components for overall smell preference and quality preference.