• Food Science and Biotechnology
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• v.18 no.6
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• pp.1398-1403
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• 2009

Present study deals with variations of physicochemicals including $\gamma$-aminobutyric acid (GABA), $\gamma$-oryzanol, free sugar, lipoxygenase activity, fat acidity, and germination rate from Korean brown rice cultivars. With increase of storage time and temperature, GABA, $\gamma$-oryzanol, lipoxygenase activity, and fat acidity increased, whereas free sugar and germination rate was reduced. Among cultivars, 'Gopumbyeo' exhibited the highest contents in GABA and $\gamma$-oryzanol during 12 weeks storage at $25^{\circ}C$ (GABA: $28.6{\pm}5.6{\rightarrow}170.4{\pm}4.6\;mg/100\;g$, $\gamma$-oryzanol: $6.1{\pm}0.7{\rightarrow}6.7{\pm}0.4\;mg/g$) and 'Ilpumbyeo' significantly decreased in free sugar during 12 weeks storage at $10^{\circ}C$ ($1,423.7{\rightarrow}1,058.4\;mg/100\;g$). Moreover, 'Taebongbyeo' exhibited the highest quality owing to low lipoxygenase activity, low fat acidity, and high germination rate. In free sugar compositions, sucrose exhibited the highest content (>70%), followed by fructose (>7%), raffinose (>5%), glucose (>3%), and maltose (>2%) during storage. Based on our results, changes of physicochemicals in stored brown rice may be important information in processing food and functional properties.

• Food Science and Preservation
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• v.3 no.1
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• pp.83-92
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• 1996

This study was conducted to estimate the shelf-life of 'Fuji' apples (Malus domestica Borkh) after CA storage. Apples stored In 1%O2+3%CO2, 2%O2+3%CO2 and 3%O2+3%CO2 at 2$^{\circ}C$ and 4$^{\circ}C$ for 8 months were stored in air at 10$^{\circ}C$, 80-85% RH for 16days. As a result of objective analysis, apples stored at 2$^{\circ}C$ wert mort effective in retarding the loss of weight flesh firmness, titratable acidity and peel color than those stored at 4$^{\circ}C$, but not the loss of soluble solid. Among storage atmospheres, 1%O2+3%CO2 at 2$^{\circ}C$ was more effective in retarding the loss of flesh firmness and green color than other atmospheres. Shelf-life of apples kept at 2$^{\circ}C$ estimated above 16 days. The contents of acetaldehyde and ethanol were not observed tn make large difference between storage conditions, but ethanol content of apples stored in 3%O2+3%CO2 at 4$^{\circ}C$ was Increased slightly for 16 days. According to sensory evaluations, apples stored at 2$^{\circ}C$ were significantly harder, juicier and more acid than chose stored at 4$^{\circ}C$. Particularly, high scores of apples stored in 1% and 2%O2+3%CO2 at 2$^{\circ}C$ Persisted for 16 days. Juiciness, hardness acidity and sweetness were related to the flesh firmness and titratable acidity. Overall acceptability was closely related to juiciness and hardness.

• Journal of Microbiology and Biotechnology
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• v.23 no.1
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• pp.76-84
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• 2013

A polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) technique followed by sequencing of the 16S rDNA fragments eluted from the bands of interest on denaturing gradient gels was used to monitor changes in the bacterial microflora of two commercial kimchi, salted cabbage, and ingredient mix samples during 30 days of fermentation at $4^{\circ}C$ and $10^{\circ}C$. Leuconostoc (Lc.) was the dominant lactic acid bacteria (LAB) over Lactobacillus (Lb.) species at $4^{\circ}C$. Weissella confusa was detected in the ingredient mix and also in kimchi samples throughout fermentation in both samples at $4^{\circ}C$ and $10^{\circ}C$. Lc. gelidum was detected as the dominant LAB at $4^{\circ}C$ in both samples. The temperature affected the LAB profile of kimchi by varing the pH, which was primarily caused by the temperature-dependent competition among different LAB species in kimchi. At $4^{\circ}C$, the sample variations in pH and titratable acidity were more conspicuous owing to the delayed growth of LAB. Temperature affected only initial decreases in pH and initial increases in viable cell counts, but affected both the initial increases and final values of titratable acidity. The initial microflora in the kimchi sample was probably determined by the microflora of the ingredient mix, not by that of the salted cabbage. The microbial distributions in the samples used in this study resembled across the different kimchi samples and the different fermentation temperatures as the numbers of LAB increased and titratable acidity decreased.

• Food Science and Preservation
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• v.23 no.5
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• pp.727-737
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• 2016

This study was carried out to determine the descriptive sensory profile of oriental melon. The sensory profile of oriental melons (cultivated in Seonju, Kyungsangbuk-do) were used quantitative descriptive analyses and twelve trained panel developed the total forty sensory attributes related appearance, aroma, texture etc. Six appearances attributes and two aromas attributes were derived from whole oriental melon with skin. Five aromas, six tastes and six textures were derived from the mesocarp of oriental melon. And also, oriental melons were analyzed for pH, titratable acidity, solid soluble contents and weight. The weight, titratable acidity and soluble solid content of oriental melons showed significant differences according to samples. And also, in the sensory attributes of these samples by trained panel and consumer test, there were significant differences between organic cultivated samples and conventional cultivated samples. Based on principal component analysis of sensory attributes data by trained panel and consumer, oriental melons were primary separated along the first principal component, which accounted for 27.73% (trained panel test) and 19.82% (consumer test) of total variance (trained panel test; 58.36%, consumer test; 46.18%) between the samples farm, cultivation method, total acidity, sweet aroma, bitterness, etc. Generally, whole oriental melon with skin showed significant differences in the sensory attributes according to cultivation method and farms. But, the mesocarp and endocarp part showed not certainly differences in the sensory attributes between organic cultivated samples except conventional cultivated samples.

• Korean Journal of Food Science and Technology
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• v.54 no.4
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• pp.455-461
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• 2022

In this study, kombucha was prepared using saccharified rice solution to assess this possible means of increasing rice consumption. Chucheong rice yielded the highest starch content (80.40±1.33%) when used to produce saccharified rice solution. The resultant saccharified rice solution showed the highest 10.42 °Brix at 90 min of saccharification. Chamdream rice yielded the highest acidity at 0.38%, and Kawaji No.1 yielded the lowest at 0.24%. Organic acid analysis on the 15th day of fermenting kombucha made with different rice varieties indicated an acetic acid content of 111.70±1.09 ppm in Chamdream, and 46.86±1.00 ppm in Dongjinchal. Comparison of enzymes used in saccharified rice kombucha fermentation revealed that α-amylase resulted in the highest acidity (1.06%), and β-amylase yielded the lowest acidity (0.58%). Kombucha with green tea yielded the highest acidity (1.09%), and kombucha with rooibos tea yielded the lowest (0.37%). Polyphenol analysis indicated that the amount of polyphenol increased the most (1,623.75 ppm to 3,989.00 ppm) on day 0 of fermentation with green tea. Organic acid analysis revealed that the acetic acid content of kombucha supplemented with green tea increased from 172.89 ppm on day 0 of fermentation to 2,649.11 ppm on day 15. Kombucha with 2.0% added alcohol had the highest acidity (1.32%), and kombucha with 0.5% alcohol had the lowest (0.97%). Taken together, these results confirm that it is possible to make kombucha using saccharified rice solutions.

• Korean journal of food and cookery science
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• v.27 no.6
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• pp.773-781
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• 2011

Coffee beans are processed from coffee cherries by either natural, pulped natural, or washing. The aim of the present study was to evaluate the physiochemical and sensory characteristics of espresso coffees processed by different methods. The color of the washed coffee sample presented the highest value of lightness while the natural coffee sample presented the highest value of redness and yellowness. The biggest difference in brewed coffee, whether natural, pulped natural, or washed, was in the TDS content, which was higher in natural coffee and lower in washed coffee. Sensory descriptive analysis and acceptance test for espresso coffee using a 15 cm line scale were carried out by 12 trained panelists. Natural coffee had the highest cherry-like flavor and sweetness taste while washed coffee had the highest citrus flavor and acidity taste. An important attribute of espresso coffee is body, and natural coffee presented strong body while washed coffee presented a low body attribute. In conclusion, significant differences were observed among the three processing methods of green coffee. Pulped natural coffees presented intermediate physiochemical and sensory characteristics compared to washed and natural coffee. Natural coffees are appreciated for their increased body, and washed coffees are appreciated for added citrus flavors and acidity espresso coffee blends.

• Journal of Environmental Science International
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• v.2 no.4
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• pp.337-346
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• 1993

The amount of inorganic ions such as $Na^+$, $K^+$, $Ca^{2+}$, $Mg^{2+}$, $NH_4^+$, $Cl^-$, $NO_3^-$, and $SO_4^{2-}$ in the precipitation at hongwon area were analyzed during the period of February 1991 - June 1993. Ammonium ion was analyzed using Messier and indophenol methods. Cations were determined by atomic absorption spectroscopy, and ion chromatography was used for anions. For the entire period of study, there was no particular ion which has significant]y high correlation coefficient with hydrogen ion. The correlation between $NO_3^-$, and $SO_4^{2-}$ was 0.6, which suggests that these ions may be from the same source. Most cations have high correlation with each other. In the seasonal analysis, the nitrate and sulfate ions have high correlations with the acidity in the fall and winter. The rain waters of Taeahn area showed usually high concentrations of the ions, even though the pH was much higher than that of Chongwon area. It is considered that the ions came as neutral salt in Taeahn, while $NO_x$ and $SO_x$ contributes largely to the acidity of rains in Chongwon.

• 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.

• Korean Journal of Food Science and Technology
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• v.20 no.5
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• pp.631-636
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• 1988

Quality of five kinds of honey, from acacia, bush clover, chestnut, rape and polyflower sources, were evaluated by physicochemical methods in respect to some chemical constituents. The average values for the tested honeys were: moisture, 19.5%; fructose, 33.74% , glucose. 35.03%; sucrose, 4.67%; hydroxymethylfurfural, 6.17mg,/kg; total nitrogen, 0.027%, proline, 23.67mg%; lactone, 4.09meq/kg; free acidity, 11.37meq /kg; and total acidity, 15.46meq/kg.

• 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.