• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.266-271
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• 2007

The pH, acidity, color, reducing sugar, total sugar, alcohol, and organoletic characteristics of Takju containing puffed rice powder (0, 25, 50 and 75%) were investigated during fermentation for 10 days. After drastic decrease at Day 1, the pH increased gradually until Day 5 and then tended to decrease after Day 6. A lower concentration of puffed rice powder resulted in a greater pH reduction (p<0.05). Acidity increased quickly with days, especially for the 0% after Day 6 (p<0.05). After a sudden rise at Day 1, the Hunter ‘L’ value tended to decrease with days of fermentation. At the same day, the 75% showed the lowest Hunter ‘L’ value, however, it had the highest Hunter ‘a’ value except on Days 0, 3 and 10 (p<0.05). After a rapid reduction in reducing sugar on Day 3, no differences were observed in the samples (p<0.05). The 75% tended to be higher in reducing sugar. Total sugar decreased rapidly at Day 2, and then either remained unchanged or decreased after Day 3. With the exception of Day 4, the 75% had higher amounts of total sugar than the others at the same day (p<0.05). The Highest alcohol contents [13.0-16.4% (v/v)] occurred on Day 6. Higher alcohol concentrations were observed with higher puffed rice powder (p<0.05). In the sensory evaluation, no differences were detected between the 0% and those with puffed rice powder added (p<0.05).

• Journal of the East Asian Society of Dietary Life
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• v.18 no.6
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• pp.981-988
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• 2008

This study was conducted to develop functional black soy sauce with (S2) and without (S3) an outer skin and then compare these products to a control soy sauce (S1). In addition, the effects of different fermentation periods on the pH, buffering power, titratable acidity, total acidity, salt content, and browning and Lab value were evaluated. Furthermore, the antioxidative activities of the black soy sauce were compared to those of the control soy sauce based on the total phenolic compounds and free radical scavenging activity, including the 1,1-diphenyl-2-picryl-hydrazil (DPPH) scavenging activity and the thiobarbituric acid value (TBA value). The pH and buffering power of S2 were lower than of S1 and S3, while the titratable acidity and total acidity were higher. The salt content of all samples decreased after 60 days of fermentation, after which it increased slightly for up to 180 days. Additionally, the browning intensity of all samples increased as the fermentation periods increased, with the browning intensity at 420 nm of S1 being the highest followed by S3 and S2. After 150 days of fermentation, the L value of S1 was higher than that of S2 and S3, but the while a value of S2 was higher than those of S1 and S3 and was increased as the fermentation periods. Moreover, the b value of S1 was the highest at the end of the fermentation period, followed by the b values of S3 and S2. The amount of total phenolics in S1 was greatest, followed by S2 and S1. Conversely, the DPPH radical scavenging activity of S2 was the highest, followed by S3 and S1. Finally, the TBA value increased rapidly from day 30 to day 180 of the fermentation period, and the TBA value of S2 was lower than those of S1 and S3.

• Journal of Ginseng Research
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• v.4 no.2
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• pp.121-132
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• 1980

In order to study the effect of Korean ginseng (Panax ginseng C. A. Meyer) components on acetic acid fermentation, ginseng extracts, sucrose, total can de saponins were added to the basal niedium respectively and surface culture was carried out at 30$^{\circ}C$. Lag ime, total acidity of the fermentation broth inhibitors and the degrees of inhibition were determined in tile course of fermentation . 1. Acetic acid fermentation was not inhibited by the addition of less than 1.93% of sucrose but the degree of inhibition was increased slightly by the addition of sucrose more than that. 2. Ginseng extract inhibited acetic acid fermentation slightly, and the degree of inhibition was similar to that of sucrose. Lag time was about 72 hours when a 20% of ginseng extract was added to the basal medium while that of the control was 22hours. 3. The free saponins inhibited acetic acid fermentation considerably, and the degree of inhibition of the saponins was about 400 folds of that of ginseng extracts. An increase of total acidity of the broth which contained 2.905% of the saponins was not observed even after one month. 4. It was presumed that some other components except saponins and sucrose in ginseng extracts counter the inbition effect of saponins on acetic acid fermentation

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.5
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• pp.319-323
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• 2014

This study investigates the prediction of soil chemical properties (organic matter (OM), pH, Ca, Mg, K, Na, total acidity, cation exchange capacity (CEC)) on 688 Korean soil samples using the visible-near infrared reflectance (VIS-NIR) spectroscopy. Reflectance from the visible to near-infrared spectrum (350 to 2500 nm) was acquired using the ASD Field Spec Pro. A total of 688 soil samples from 168 soil profiles were collected from 2009 to 2011. The spectra were resampled to 10 nm spacing and converted to the 1st derivative of absorbance (log (1/R)), which was used for predicting soil chemical properties. Principal components analysis (PCA), partial least squares regression (PLSR) and regression rules model (Cubist) were applied to predict soil chemical properties. The regression rules model (Cubist) showed the best results among these, with lower error on the calibration data. For quantitatively determining OM, total acidity, CEC, a VIS-NIR spectroscopy could be used as a routine method if the estimation quality is more improved.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.2
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• pp.159-167
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• 2017

In this study, quality characteristics of yakju fermented with byeo-nuruk prepared using rice, wheat, and water were investigated. Five different mixture ratios were considered for byeo-nuruk preparation. A comparative analysis of commercial yakju and byeo-nuruk yakju was also performed. The results showed no significant differences in pH, total acidity, and total soluble solids of byeo-nuruk yakju immediately following fermentation. The byeo-nuruk yakju alcohol content increased with increasing wheat proportion. Lactic and succinic acid were the major organic acids of byeo-nuruk yakju, and the major volatile components were isoamyl alcohol and linalool. Yakju prepared using material D had the highest volatile component content and high preference evaluation scores for taste and overall acceptability. Compared to commercial yakju, byeo-nuruk yakju had less total acidity, soluble solids, and volatile acids, whereas its pH level and amino acid content were higher. No significant differences were observed between commercial yakju and byeo-nuruk yakju in terms of sensory evaluation.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.6
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• pp.582-590
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• 2004

The purpose of this study was to investigate the effect of maesil(Prunus mume) on Dongchimi fermentation. Dongchimi with 0, 2, 4 and 6%(w/v) maesil was fermented at 10℃ for 45 days. The pH of Dongchimi decreased slowly in all samples during fermentation. Total acidity of Dongchimi increased gradually during fermentation and total acidity of Dongchimi with maesil was higher than that of control. Redox potentials decreased until 30 days of fermentation but increased thereafter. Reducing sugar content increased in the initial stage of the fermentation periods, and then it decreased gradually, the reducing sugar content of Dongchimi with maesil was higher than that of control. The content of total vitamin C was much higher in Dongchimi with maesil. In color measurement, lightness value decreased gradually, redness and yellowness values increased gradually during fermentation but decreased thereafter. The content of hot water soluble pectin(HWSP) decreased as the fermentation proceeded but the content of hydrochloric acid soluble pectin(HCISP) and sodium hexametaphosphate soluble pectin(NaSP) increased.

• Korean journal of food and cookery science
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• v.19 no.5
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• pp.624-630
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• 2003

The physicochemical properties and antioxidant activities of commonly consumed espresso and regular coffees, at coffee shops in downtown Seoul, were investigated. Moreover, the characteristics between chain type coffee shops and owner shops were compared using t-tests. The serving temperature and volume of espresso were lower than those for regular coffees. Whereas, the pH and total acidity of espresso were higher than those for regular coffees. Coffees from chain shops, in particular, had a significantly higher pH and lower total acidity than those from owner shops. The L, a and b values of the regular coffees were higher than those of the espresso coffees. With the exception of the a value of regular coffees, all the color values of the coffees from owner shops were higher than those from the chain shops. The intensity of the brownness, soluble solid contents and total phenolic contents of the espresso coffees were about 7∼8, 8∼9 and 4 times higher, respectively, than those of regular coffees. In addition, the free radical scavenging capacities and antioxidant activities of the espresso coffees, using a chemiluminescence assay, were higher than those of regular coffees. Espresso coffees from chain shops, especially, had higher activities of free radical scavenging than those from owner shops. In conclusion, the characteristics of coffees from chain shops were significantly different from those from owner coffee shops.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.801-807
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• 2016

In Western countries, kimchi, the Korean traditional fermented cabbage, is considered to be a healthy. However, it is one of the main sources of the high sodium content of the Korean diet. In order to decrease the sodium content, we manufactured a low-sodium kimchi (LK, salinity 1.0%) and 4 additional low-sodium kimchi starters in which each of 4 lactic acid bacteria (Lb. sakei 1, Lb. sakei 2, Lb. palntarum and W. koreensis) were added. The LKL1 to LKL4 samples were prepared by adding 4 single LAB starters, each with an inoculum size of $10^6CFU/g$, when the cabbage was mixed with kimchi sauce. The kimchi starters were fermented at $10^{\circ}C$ until reaching 0.5% acidity, and then stored at $-1.5^{\circ}C$ until reaching 0.75% acidity. The pH and acidity of the starter kimchi changed more rapidly in the early phase of fermentation (up to 0.75% acidity) than control low-sodium kimchi. After the acidity of the kimchi starters reached 0.75% it remained constant. As the fermentation progressed, the total aerobic and lactic acid bacteria concentrations in the kimchi starter with added Lb. sakei 1 were the same as in the control low-sodium kimchi. The low-sodium kimchi fermentation of the kimchi starter with added Lb. palntarum progressed differently due to a difference in acid resistance. The kimchi starter with added Lb. sakei 2 had an overall liking score that was slightly higher than that of the control low-sodium kimchi due to a lower off-flavor.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.6
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• pp.695-702
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• 2017

This study was carried out to investigate the effects of seed vinegar on antioxidant activity and antimicrobial activities of concentrated blueberry vinegar (CBV). Of the nine strains of yeast and six strains of acetic acid bacteria provided by the Microbial Institute for Fermentation Industry, each strain of yeast (Saccharomyces cerevisiae SRCM 100610, showing the highest ethanol content) and acetic acid bacteria (Acetobacter pasteurianus SRCM 101342, showing the highest total acidity) was selected for production of CBVs. Sugar content, pH, total acidity, total phenolic content (TPC), and browning intensity (280 nm and 420 nm) in CBVs using concentrated blueberry juice were $11.05{\sim}12.70^{\circ}Brix$, 2.63~2.98, 1.65~5.72%, 3.03~4.24 mg/mL, 0.95~1.50, and 0.11~0.20, respectively. Sugar content and total acidity of CBVs increased upon addition of seed vinegar, whereas pH, TPC, and browning intensity decreased. Of all CBVs with various additions of seed vinegar, the control showed the lowest $EC_{50}$ values in DPPH radical scavenging assay, ABTS radical scavenging assay, and reducing power (23.80, 19.48, and 79.21 dilution factor, respectively), whereas the 40% seed vinegar group showed the highest clear zone diameter values for Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and Bacillus cereus (4.31, 4.59, 5.81, and 3.97, respectively). Antioxidant activities of CBVs were closely correlated with their TPC, browning intensity at 280 nm, pH, and total acidity values, showing correlation determination coefficient ($R^2$) values higher 0.82. However, antimicrobial activities of CBVs were closely correlated with their pH and total acidity values, showing higher $R^2$ values more than 0.92. These results suggest that CBVs using concentrated blueberry juice, S. cerevisiae SRCM 100610, and A. pasteurianus SRCM 101342 may be useful as potentially functional foods for enhancing health.

• The Korean Journal of Food And Nutrition
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• v.34 no.6
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• pp.641-649
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• 2021

The objective of this study was to evaluate the quality characteristics of mozzarella cheese added wine concentrate. Mozzarella cheese was produced with different additives of wine concentrate which were 0~5%. The pH and the total acidity of the Cheese were analyzed. We also examined the radical scavenging activities for the antioxidant effect of samples and evaluated for their total polyphenol, and total flavonoid contents. The pH of Meoru wine cheese (6.28~6.37) was significantly higher and total acidity tended to decrease compared to that of the control. L^* (lightness) of the wine cheese decreased with increasing amounts of wine concentrates whereas a^* (redness) tended to increase. In the texture profile analysis, Meoru wine cheese showed higher values of hardness, gumminess, and chewiness. The ABTS radical scavenging activity of Meoru wine cheese showed the highest value when wine concentrate amounts were 2%. The DPPH radical scavenging activity was significantly increased in cheese added with wine concentrate. Total polyphenol contents and total flavonoid contents of Meoru wine cheese tended to increase with increasing amounts of wine concentrate. This research result highlights the positive influence of wine concentrate addition in cheese. Also, these results are expected to impact the experience programs in farm wineries.