• Journal of Sericultural and Entomological Science
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• v.51 no.2
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• pp.164-172
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• 2013

This study was carried out to investigate functional quality characteristics of extract obtained after sugar-leaching for 12 weeks (SLE) and extract obtained after lactic acid fermentation for 8 weeks (LFE) of mulberry leaves. The yield, sugar content, pH, and total acidity of SLE were 27%, 43 $^{\circ}Brix$, 4.6, and 0.45%. The yield, sugar content, pH, and total acidity of LFE were 166%, 33 $^{\circ}Brix$, 3.6, and 1.17% respectively. The lactic acid bacteria viable numbers ($1.2{\times}10^{10}$ CFU/ml) of LFE were more than those of SLE ($2.8{\times}10^2$ CFU/ml). The LFE expressed activities of hydrolytic enzymes (amylase, cellulase, pectinase, protease), but SLE did not express. The contents of acetic acid, citric acid, and malic acid of SLE were higher than those of LFE, but lactic acid content of LFE was higher than that of SLE. The main free sugars of SLE were glucose (200.93 mg/g), fructose (236.32 mg/g), and sucrose (18.41 mg/g), but LFE did not detect all free sugars. The contents of polyphenol, anthocyanin, and piperidine alkaloid of LFE were higher than those of SLE. ${\alpha}$-Glycosidase activities were inhibited 3.4% and 16.2% by SLE and LFE. These results suggest that lactic acid fermentation extraction is an effective method to increase the yield and contents of functional quality of mulberry leaves extract.

• Food Science and Preservation
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• v.18 no.1
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• pp.46-52
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• 2011

Wild grape juice was fermented by Gluconacetobacter hansenii TF-2 isolated from tea fungus, to develop a new acidic beverage (fermented wild grape beverage, WGB). Broth was prepared by fermentation of 11~17% (v/v) juice, and sweetened with sucrose (initial sucrose level: $10^{\circ}$ Brix). Fermentation was initiated by addition of 5% (w/v) seed gel (the pellicle of the tea fungus) which had been previously cultured in the same medium (freshjuice broth), and fermentation proceeded in the dark at $29{\pm}1^{\circ}C$ for about 15 days. The major acids produced were succinic acid, malic acid, and acetic acid. After 15 days of fermentation, the organic acid content (principally succinic acid) was 49.6 ppm in WGB 11 and 77.4 ppm in WGB 17. The free sugar content of WGB was 1063.6-1082.5 mg/mL, composed of unfermented fructose, glucose, and sucrose, in that order. The microbial inhibitory effects of the fermented beverage were most apparent when Gram-negative bacteria (Escherichia coli and Salmonella typhimurium) were tested; the inhibition rate was 34.46-88.00%. The new fermented beverage thus displays effective antimicrobial activity against some species of bacteria.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.5
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• pp.660-665
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• 2008

The aim of this work was to investigate the microbiological and physicochemical properties of the rice sourdough for Jeungpyun prepared by mixed culture of Saccharomyces cerevisiae (S. cerevisiae) and Leuconostoc mesenteroides (L. mesenteroides) strains. The rice sourdough was fermented with S. cerevisiae and L. mesenteroides strains in rice dough for 24 hours at $30^{\circ}C$. Growth of L. mesenteroides strain was decreased after inoculation, however, it increased again after 18 hours of dough fermentation, and the growth of S. cerevisiae showed a typical growth pattern. Also, total aerobic microorganisms counts in rice sourdough were decreased due to the produced organic acids and ethanol during dough fermentation. These products led to a favorable fermentative quotient (FQ; molar ratio between lactic to acetic acid) value of $1.9{\sim}3.2$ and more stable fermentation for rice sourdough formation. The expansion ratio and viscosity were considerably increased by mixed cultivation of S. cerevisiae and L. mesenteroides strains. Addition of the brown rice at 10% (w/w) to dough preparation increased the relative expansion ratio to the highest value.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.4
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• pp.566-571
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• 2002

Volatile flavor compounds in Alaska pollack sik-hae during fermentation at 5$^{\circ}C$ were analyzed by liquid-liquid continuous extraction (LLCE) and gas chromatography/mass spectrometry (GC/MS) methods. Sixty five volatile compounds were detected in Alaska pollack sik-hae during fermentation. These compounds were composed mainly of 11 S-containing compounds, 13 alcohols, 13 acids, 4 aldehydes, 4 ketones, 6 terpenes,4 aromatic compounds and 10 miscellaneous compounds. Among these, 9 S-containing compounds (3-(methylthio)-1-propene, dimethyl disulfide, diallyl sulfide, methylallyl disulfide, methyl-(E) -propenyl disulfide, dimethyl trisulfide, 2 diallyl disulfide isomers and diallyl trisulfide), 2 acids (acetic acid and butanoic acid), 2 ketones (2, 3-butanedione and 6-methyl-5-hepten-2-one) and 2 esters (ethyl formate and ethyl acetate) were significantly increased during fermentation (p<0.05), and these compounds were suspected to affect on the odor of Alaska pollack sik-hae.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.9
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• pp.1295-1303
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• 2013

The aim of this study was to determine the effect of different physical forms and urea treatment of rice straw on feed intake, rumen fermentation, and milk production. Four, multiparous Holstein crossbred dairy cows in mid-lactation with initial body weight (BW) of $409{\pm}20kg$ were randomly assigned according to a $4{\times}4$ Latin square design to receive four dietary treatments. The dietary treatments were as follows: untreated, long form rice straw (LRS), urea-treated (5%), long form rice straw (5% ULRS), urea-treated (2.5%), long form rice straw (2.5% ULRS) and urea-treated (2.5%), chopped (4 cm) rice straw (2.5% UCRS). Cows were fed with concentrate diets at a ratio of concentrate to milk yield of 1:2 and rice straw was fed ad libitum. The findings revealed significant improvements in total DM intake and digestibility by using long and short forms of urea-treated rice straw (p<0.05). Ruminal pH was not altered among all treatments (p>0.05), whereas ruminal $NH_3$-N, BUN and MUN were found to be increased (p<0.01) by urea-treated rice straw as compared with untreated rice straw. Volatile fatty acids (VFAs) concentrations especially those of acetic acid were decreased (p<0.05) and those of propionic acid were increased (p<0.05), thus acetic acid:propionic acid was subsequently lowered (p<0.05) in cows fed with long or short forms of urea-treated rice straw. The 2.5% ULRS and 2.5% UCRS had greater microbial protein synthesis and was greatest when cows were fed with 5% ULRS. The urea-treated rice straw fed groups had increased milk yield (p<0.05), while lower feed cost and greater economic return was in the 2.5% ULRS and 2.5% UCRS (p<0.01). From these results, it could be concluded that 2.5% ULRS could replace 5% ULRS used as a roughage source to maintain feed intake, rumen fermentation, efficiency of microbial protein synthesis, milk production and economical return in mid-lactating dairy cows.

• Journal of Life Science
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• v.14 no.1
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• pp.67-71
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• 2004

Oriental melon vinegar was prepared by two stage fermentations of alcohol and acetic acid. In the alcohol fermentation using oriental melon residual products, alcohol content showed 7.43% in 17$^{\circ}$ brix of initial sugar concentration and 80 h of fermentation time. In the acetic acid fermentation using oriental melon alcohol, acidity showed 5.25% in 250rpm of agitation rate and 200 h of fermentation time. The cultivation esults of oriental melons using its vinegar are as follows. Quantity and quality of samples treated with 500, 1,000 and 2,000 times of oriental melon vinegar were higher than that of control : weight, quality, sugar content and goods production rate were higher to degree of 33∼42 g/piece, 370 ∼460kg/10a, 0.6∼.9$^{\circ}$ Brix, 2∼5%, respectively. Coods production yield of samples treated with 500, 1,000 and 2,000 times of oriental melon vinegar was higher (400∼610 kg/10a) than that of control. The results of control of powdery mildew on oriental melons using oriental melon vinegar as the diluted solution with 500 and 1000 times were identical for control value that used by agrochemical. Powdery mildew were exterminated by 2nd treatment of the diluted solution. In case of aphids, the diluted solution with 500, 1,000 and 2,000 times of oriental melon vinegar exterminated thoroughly by 2nd treatment.

• Journal of the Korean Wood Science and Technology
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• v.38 no.6
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• pp.561-567
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• 2010

In this study, we evaluated optimal conditions for ethanol production of the spruce hydrolysate (SH) obtained from diethyl oxalate pretreatment. Fermentable sugar concentration in SH was 29.04 g/${\ell}$ except arabinose. Monosaccharides obtained from the oligomer degradation were mainly mannose (39.26 g/${\ell}$) and galactose (12.83 g/${\ell}$). Concentration of 5-HMF and furfural which are inhibitors on ethanol fermentation were 0.09 g/${\ell}$ and 0.04 g/${\ell}$ respectively. Concentration of acetic acid and total phenolic compounds in SH were 1.4 g/${\ell}$ and 2.83 g/${\ell}$. Ethanol production using hydrolysate was 11.7 g/${\ell}$ at optimal pH 6.0 after 48 h. Specific ethanol production was 0.15 (g/(${\ell}^*h$)) at pH 5.0 and 5.5. while that was 0.24 (g/(${\ell}^*h$)) at pH 6.0. Specific ethanol production has difference depend on initial pH for fermentation. Ethanol production was 14.3 g/${\ell}$ after 48 h when xylanase 20 IU was added in SH for degradation of oligomer during fermentation. It implied that ethanol production increased by 22.2% compare with control (without xylanase).

• 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.

• Applied Biological Chemistry
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• v.45 no.3
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• pp.138-144
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• 2002

In order to improve the quality of foxtail millet wine, zymological properties by isolated strains from Nuruk were investigated. Saccharomyces sp Y5-1 as brewing yeast, Aspergillus sp. M6-3, Aspergillus awamori 6970, and Aspengillus usamii mut. shirousamii 6959 (KCTC) as saccharifying molds were used, respectively. Acid content, soluble solids, color (b) and alcohol contents were increased during fermentation. Ethanol concentration of millet wine made with Nuruk by Aspergillus awamori 6970 and Aspergillus usamii mut. shirousamii 6959 were higher than the other, 10.6 and 10.1% respectively. Citric acid was only detected on $1{\sim}2$ day starting fermentation. Oxalic acid, lactic acid and acetic acid of millet wine were high in the wine made of Nuruk by Aspergillus usamii mot. shirousamii 6959, Aspergillus awamori 6970 and traditional Nuruk, respectively. During fermentation, glucose and xylose was higher than the others. Xylose was increased, but most of other sugar were decreased during fermentation. Acetone, ethyl acetate, methanol, ethanol, n-propanol, iso-buthanol and iso-amyl alcohol were detected In the wine made with Nuruk by Aspergillus awamori and Aspergillus usamii mut. shirousamii, iso-imyl alcohol and ethanol were high. On sensory evaluation, the wine made with Nuruk by Aspergillus usamii mut. shirousamii was the best on color and taste.

• Food Science and Preservation
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• v.22 no.1
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• pp.100-107
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• 2015

This study was conducted to develop a high-acidity vinegar production (over TA 10%) technology using grape juice to reduce the importation of high-acidity vinegar. The manufacturing condition's effect on the quality of high-acidity vinegar using pure grape juice without the addition of other nutrients for fermentation was investigated. Twelve percent acidity in vinegar was obtained from grape wine with 6% alcohol content. The acetic-acid yield from grape wine decreased when the wine's initial alcohol content was high, which extended the induction time. The pH value was similar in all the treatment groups. The sugar content of the 1st-stage fermentation (1st AAF) was proportional to the initial alcohol content whereas in the 2nd-stage fermentation (2nd AAF), the sugar content was highest in the 6%-alcohol treatment. The major organic acids of the high-acidity grape vinegar included tartaric acid, malic acid, and citric acid. The acid content of the high-acidity initial alcohol group was higher than that of the low-acidity initial alcohol group due to the alcohol content added by the fed-batch and acetic-acid yield difference. The ethyl alcohol content was 364~6,091 ppm (the main alcohol while the others had only traces in all the groups). In conclusion, it was possible to manufacture 12% high-acidity vinegar without the addition of an external nutrient source to grape wine containing 6% initial alcohol content. Finally, a complementary study will be required to shorten the fermentation period through the fed-batch-style addition of alcohol for the purpose of industrialization.