• Korean Journal of Food Science and Technology
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• v.54 no.2
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• pp.228-234
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• 2022

Various types of tea have been cultivated to obtain different flavors and enhance their functional properties. The objective of this study was to investigate the physicochemical properties of γ-aminobutyric acid (GABA) teas produced from commercial Korean green, white, and black teas. The concentration of total minerals was reduced in GABA green tea and GABA white tea but was improved in GABA black tea. The essential, non-essential, and total free amino acid contents were remarkably increased in the GABA teas. The amino acid GABA content was increased by 561.00 and 294.20 times in GABA white tea and GABA black tea, respectively. The antioxidant potential was not reduced, although the total polyphenol and total flavonoid contents decreased in GABA green tea and GABA black tea. The results indicated that the overall nutritional value of commercial green, white, and black teas could be improved by processing them into GABA teas.

• Korean journal of food and cookery science
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• v.31 no.6
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• pp.773-780
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• 2015

Lactic acid fermentation of black raspberry (Rubus occidentalis) juice was carried out by using the Lactobacillus plantarum GBL17 strain. The sterilized black raspberry juice was fermented using the L. plantarum GBL17 strain at $30^{\circ}C$ for 72 hours after which the total acidity increased and the pH value decreased. In addition, the highest total acidity content (2.38%) was reached, the lowest pH value (3.22) was observed, and the sugar content decreased by $9.8^{\circ}Brix$ after the 72 hour fermentation. The number of viable cells rapidly increased up until 24 hours, after which it gradually decreased. HPLC analysis of the organic acids showed 14.51 mg/g of lactic acid content in the fermented black raspberry juice, which was not detected in the non-fermented black raspberry juice (control). The content of fructose and glucose slightly decreased after fermentation. The total polyphenol and flavonoid contents of the fermented black raspberry juice increased significantly after fermentation. The DPPH radical scavenging activity of fermented black raspberry juice (70.92%) was higher than that of the control (62.96%). After lactic acid fermentation, there was no significant increase in ABTS radical scavenging activity. These results confirm that lactic acid bacteria, such as L. plantarum GBL17, showed generally higher activities with a potential as a functional beverage.

• Journal of the Korean institute of surface engineering
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• v.36 no.4
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• pp.317-323
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• 2003

The effect of additives such as complexing agents, stabilzers and boric acid on the bath stability and the deposition rate of electroless black Ni-Zn plating has been examined. The deposits obtained became black and showed an amorphous structure. The significant increasing in the deposition rate was not found when only glycine and citric acid were used as complexing agents. The deposition rate increased up to 3 and 4 times by adding malic acid and glycolic acid as an additional complexing agent, respectively. The stabilizers and the boric acid, however, had little influence on the deposition rate.

• Korean Journal of Agricultural Science
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• v.37 no.2
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• pp.261-266
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• 2010

In this study, we determined lipid content, total fatty acid composition, trans fatty acid(tFA) content, and acid value of twenty black-bean-sauce noodles collected in Seoul city area. Total lipid contents of twenty samples were determined to be 3.33~9.23% on wet base. Total unsaturated fatty acids were from 47.83% to 83.18%(mainly oleic and linoleic acid). Total saturated fatty acids ranged from 16.06% to 51.48%. Besides, tFA contents in total lipid of samples were ranged from 0.38% to 1.39%, equivalent to 20 to 80mg per 100g of black-bean-sauce noodles. Acid values of lipids extracted from samples ranged from 0.56 to 2.88.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.2
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• pp.182-191
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• 2012

Black rice bran powder has potential medical uses and functionality. In this study, we assessed the antioxidant activity and quality characteristics of cookies containing various concentrations (0, 1, 3, 5, 7, and 9%) of black rice bran powder. To analyze quality characteristics, proximate composition, fatty acid composition, amino acid composition, bulk density and pH of the dough, spread factor, loss rate, leavening rate, color, texture profile analysis, and sensory evaluations were measured. Black rice bran cookies (7%) contained more crude protein ($10.67{\pm}0.33$%) compared to control ($5.84{\pm}0.06$%). The total unsaturated fatty acid contents of the control and 7% black rice bran cookies were 30.44 and 30.81%, respectively. The amino acid content of 7% black rice bran cookie was higher than that of control. Bulk density of the dough, moisture, spread factor, total polyphenol content, and DPPH free radical scavenging activity of the cookies significantly increased with increasing content of black rice bran powder, whereas pH of the dough, loss rate, leavening rate, and L values of the cookies decreased. Additionally, consumer acceptability scores for the 7% black rice bran cookie group ranked significantly higher than those of the other groups in terms of appearance, taste, flavor, texture, and overall preference. Taken together, the results of this study suggest that black rice bran powder is an effective ingredient for increasing the consumer acceptability and functionality of cookies.

• Korean Journal of Agricultural Science
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• v.45 no.4
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• pp.799-809
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• 2018

This study was performed to compare the physicochemical characteristics between imported dry-cured Hams from black and white pigs available in the domestic market. The black dry-cured hams contain higher moisture and ash contents than that of white hams, whereas the black dry-cured hams had lower fat contents than that of the black ones (p < 0.05). The hams from black ones had lower lightness ($L^*$) and yellowness ($b^*$) values than those from the white ones (p < 0.05). Moreover, the pH values and salt contents of the hams from the black ones were higher than those from the white ones (p < 0.05). Moreover, the black ones had a higher water holding capacity (WHC) than that of the white ones (p < 0.05). The thiobarbituric acid reactive substances (TBARS) values of the black ones were lower than those of the white ham samples (p < 0.05). For texture profile analysis, hardness, gumminess, chewiness, cohesiveness and shear force values were significantly lower in the black ones than in the white samples (p < 0.05). Saturated fatty acids in the white ones were higher than in the black ones, whereas unsaturated fatty acids in the black ones were higher (p < 0.05). Free amino acids such as aspartic acid and glutamic acid in the black ones were higher than in the white ones (p < 0.05). The shrinkage of muscle fiber was stronger in the white ones. Considering the meat quality parameters of ham, the black ones showed a superior meat quality. In general, this research can be used as fundamental information for the mass production of dry-cured hams in Korea.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.42-45
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• 2005

Accurate prediction of the fate and transport of contaminants in soils and sediments is very Important to environmental risk assessment and effective remediation of contaminated soils and sediments. The fate and transport of contaminants in subsurface are affected by geosorbents, especially carbonaceous materials including black carbon. Various physical and chemical treatment methods have been developed to separate different kinds of carbonaceous materials from soils and sediments. However, the effects of these separation methods on the properties of remaining carbonaceous materials including sorption capacity and linearity are unclear. The objective of this study is to determine if the chemical and thermal treatment methods previously used to separate different carbonaceous material fractions affect the properties of carbonaceous materials including longer term sorption capacity of hydrophobic organic contaminants. The results indicate that treatments with hydrochloric acid (HCl)/hydrofluoric acid (HF), trifluoroacetic acid (TFA), sodium hydroxide (NaOH) may not affect the sorption capacity of black carbon reference materials such as char and soot, however, treatments with acid dichromate $(K_2Cr_2O_7/H_2SO_4)$ and heat $(375^{\circ}C)$ for 24 hours in sufficient of oxygen) decrease the sorption capacity of them. The results of longer term sorption isotherm indicate that 2 days might be enough for trichloroethene (TCE) to equilibrate apparently with treated black carbon reference materials. The results suggest that acid dichromate and heat treatments may not appropriate method to investigate sorption properties of black carbon in soils and sediments.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.12-16
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• 2002

In this study, the physicochemical properties of warty black and glutinous rice flours were compared. Crude protein content of waxy black rice flour (9.01%) was higher than than of glutinous rice flour (7.54%). Most mineral contents of waxy black rice flour were higher than those of glutinous rice flour. The major fatty acids in the waxy black and glutinous rice flours were oleic acid (38.57% and 36.95%) and linoleic acid (38.60% and 39.10%). The major detected amino acids of both samples were aspartic acid, glutamic acid and arginine. Water binding capacity of waxy black rice flour (93.26%) was higher than that of glutinous rice flour (87.42%) . Swelling powers and solubilities of waxy black rice flour were lower than those of glutinous rice flour in according to increasing temperatures. Maximum absorbance wavelength (λ$_{max}$) and absorbance at 625 nm were similar between both samples. X-ray diffraction patterns of both samples showed traditional A type as Peaks 2$\theta$ at 15.1$^{\circ}$, 17.1$^{\circ}$, 18.0$^{\circ}$and 23.2$^{\circ}$. The relative crystallinities of waxy black and glutinous rice flours were 0.40 and 0.41, respectively.

• Journal of Nutrition and Health
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• v.19 no.3
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• pp.190-198
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• 1986

The result of the analytical experimental by HPLC on amino acid which is contained in such samples as white-raw-sesame, white-roast -seasame, black -raw -sesame, black-roast-sesame, raw-perilla seed and roast-perilla seed is as follows ; In the six smaples, the amino acid contents in raw seeds were all higher than those in roasted seeds, and the contents of alutamic acid and lysine were more reduced in roasted seeds than in raw seeds. All the amino acid contents except threoninewere highest in raw perilla seed. The amino acids which the six samples contain to a higher degree were in order of glutamic acid (18 %-21%), threonine(16%-19%), glycine (8%-9%), leucine(77.5%), aspartic acid (7%-7.4%), while methinine (1-2%) was contained least in all six samples followed by Isoleucine(3%).

• Korean Chemical Engineering Research
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• v.54 no.6
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• pp.753-761
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• 2016

Liquid-liquid extraction (LLE) can be used for the recovery of acetic acid from black liquor prior to bioethanol fermentation. Recovery of value-added chemicals such as acetic-, formic- and lactic acid using LLE from Kraft black liquor was studied. Acetic acid and formic acid have been reported to be strong inhibitors in fermentation. The study elucidates the effect of three reaction parameters: pH (0.5~3.5), temperature ($25{\sim}65^{\circ}C$), and reaction time (24~48 min). Extraction performance using tri-n-octylphosphine oxide as the extractant was evaluated. The maximum acetic acid concentration achieved from hydrolyzates was 69.87% at $25^{\circ}C$, pH= 0.5, and 36 min. Factorial design was used to study the effects of pH, temperature, and reaction time on the maximum inhibitor extraction yield after LLE. The maximum potential extraction yield of acetic acid was 70.4% at $25.8^{\circ}C$, pH=0.6 and 37.2 min residence time.