• Journal of the Korean Society of Food Science and Nutrition
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• v.11 no.1
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• pp.25-30
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• 1982

To evaluate the quality of commercial dehydrated tea-products, the relationships between particle sizes, densities, moisture absorption & desorption and color appearance were studied by using Hunter-lab tristimulus colorimeter and spectrophotometer. Among the tea-products was held no significant relation between particle sizes and color appearance but red ginseng extract powder (RGEP) was included L, a and b values when was reduced particle size. appearance color of tea-products indicated red-orange color, L, a and b values were ranged 32.7 to 48.0, 4.0 to 10.0 and 5.6 to 18.0, respectively, densities of tea-products ranged 0.232 to 0.898 g/ml and increased L values, Hunter's a/b ratio values was included in 0.61 to 0.90. Color stability in this products was well agreed with decrease of total color difference value ($\Delta$E) and chromaticity difference value ($\Delta$C) of the Hunter-lab color data.

• Journal of Life Science
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• v.11 no.6
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• pp.568-573
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• 2001

Sea lettuce(Monostrima nitidum) were treated with several alkali agents on condition with water blanching at 9$0^{\circ}C$ for 10 min., and followed by drying and powdering, thus, the power samples treated and the not treated were then allowed to be stored at $25^{\circ}C$, dark place for 5 months. The sea lettuce powder samples were evaluated for green color intensity and volatile flavor at a month intervals. The green intensity of the samples were measured by using Hunter-lab colorimeter, therefore, the decoloration of greenness were seen in both of the samples treated and the not treated, but there were slight inhibitory effects on decoloration in the treated with alkali agents, especially in the treated with KHCO$_3$.The volatile flavor of the samples were collected by simultaneous distillation-extraction, and then the 31 flavor compounds were separated on HP-5 capillary column(25m$\times$0.25mm i.d) and identified by using GC-MS. From these results, it was presumed that the characteristic impact flavor compounds were $\beta$-cyclocitral, $\beta$-cyclohomocitral, ionene, $\alpha$-ionone and $\beta$-ionone. The total content of the characteristic impact flavor compounds decreased in the samples treated with alkali agents more alkali agents more than in the not treated, but lee decrease was observed in the treated with KHCO$_3$.

• Journal of the Korean Society of Food Culture
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• v.7 no.2
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• pp.105-112
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• 1992

The general properties(size, shape, fruit constituents) of ten different varieties of dried red pepper and the proximate chemical composition, carotenoids content and Hunter color values of their powders were examined in order to establish an objective instrumental method to evaluate the consumer acceptability of red pepper powder. The results of instrumentally measured color values were compared with the sensory acceptability data obtained from 100 housewives in Korea. Red carotenoid consisted of 68-85% of total carotenoids, while ${\beta}-carotene$ content showed close relationship with the sensory color preference. The values of Hunter color system, L,a,b and axL, showed significant relationships with the sensory color preference. Especially, axL value had close relationship with both color preference and pungency intensity of red pepper. Therefore, we suggest the consumer acceptability of red pepper powder can be determined instrumentally by axL value of colorimeter. Sensory acceptability=0.02001(axL)-12.5774

• Journal of the Korea Furniture Society
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• v.19 no.3
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• pp.156-162
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• 2008

Three major domestic softwoods, Korean red pine, Korean pine and larch, were heat-treated at $220^{\circ}C$ and for various treatment times for color changing. A new heat treatment equipment was developed for this study and was revealed working well for changing the colors of the three softwoods. The color difference index of 15 was obtained after 8 hours for Korean red pine and Korean pine, and 10 hours for Larch. The correlations of brightness, redness and yellowness with treatment time were different between species.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.224.1-224
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• 2003

The production of black rice in Korea has been increasing, as more Koreans are tending to blend black rice with medium-grain rice for serving. This increased production creates an opportunity for developing new products. In this study, the properties of sponge cakes produced from a blend of black rice flour (BRF) and wheat flour (WF) are investigated. Black rice sponge cakes (BRSC) were produced with constant process variables (e.g. baking temperature, fermentation time and BRP content (10, 20 & 30%)). Proximate compositions, farinogram, amylogram and extensogram analyses of BRSC were determined by AACC method. BRSC color was expressed to Hunter L, a and b values using a colorimeter. Sensory properties were evaluated by a trained 5-member panel. Moisture contents in BRSC decreased with increasing contents of BRF, while ash and protein contents were increased. Farinograph and amylograph data did not differ significantly between treatments, while extensograph data decreased with increasing BRF contents. With increasing BRF contents, Hunter L value decreased, while Hunter a value increased. When using 20% of BRP, sensory scores of BRSC were the highest in color, flavor and taste. In conclusion, 20% of BRF would be the optimum amount for producing sponge cake with BRP and WF.

• Food Science and Biotechnology
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• v.16 no.3
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• pp.374-380
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• 2007

Chemical and sensory profiles of 5 Korean commercial rice wines (yakju) were developed using descriptive, physicochemical, and volatile analyses. Color, 6 aroma, and 5 taste attributes of these rice wines were evaluated by a panel of 13 judges. Sample wines were analyzed for titratable acidity, ethanol content, pH, Hunter colorimeter value, organic acids, and free sugars. Volatile analysis of the samples revealed the presence of 2 acids, 7 alcohols, 19 esters, and 5 miscellaneous compounds. Based on principal component analysis of the descriptive data, rice wines were primarily separated along the first principal component, which accounted for 57% of the total variance between the rice wines with high intensities of 'color' and 'sweet aroma' versus 'ginseng' aroma.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.1
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• pp.55-60
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• 2009

This study was conducted to measure tea surface colors using the visible bands ($400{\sim}700$ nm) with near-infrared spectroscopy (NIRS). The surface colors of 117 tea products were measured with a colorimeter. The $a^*/b^*$ (CIE color scale) or a/b (Hunter color scale) ratios in different tea products accounted for about 99.7% of the variation in fermentation degree (FD), indicating that the $a^*/b^*$ (a/b) ratio is a very useful trait for assessing fermentation degree. Also tea powders were scanned in the visible bands used with NIRS. Calibration equations for surface colors and fermentation degree were developed using the regression method of modified partial least-squares (MPLS) with internal cross validation. The equations had low SECV (standard errors of cross-validation), and high $R^2$ (coefficient of determination in calibration) values with $0.779{\sim}0.999$, indicating that the whole bands ($400{\sim}2500\;nm$) with NIRS could be used to rapidly measure traits related to surface color, fermentation degree and other chemical components in tea products with high precision and ease at a time.

• Korean Journal of Food Science and Technology
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• v.34 no.2
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• pp.164-169
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• 2002

Five kinds of red wine from three different grape varieties, such as Gerbong (G), Campbell (C), Moru (M), Gerbong+Moru (70:30, GM), and Gerbong+Campbell(70:30, GC) were prepared in the year of 2000. The total phenolic content and color changes were monitored using hunter colorimeter and spectrophotometry methods during wine processing. The total phenolic content of Gerbong (G), Campbell (C), Moru (M), Gerbong+Moru(70:30, GM), and Gerbong+Campbell(70:30, GC) were 712.6 mg/L, 3472.9 mg/L, 2209.4 mg/L, 2019.4 mg/L, and 1184.5 mg/L, respectively. Between total phenolic content and hunter colorimeter value (L, a, and b) of red wine showed no significant difference, but that of spectrophotometry color value (hue and intensity) were significantly different (p<0.001). The total phenolic content, hue, and intensity values represented significantly different between grape varieties (p<0.01, p<0.001). the hue showed a negative correlation relationship $(r^2=0.8660,\;p<0.0001)$, and that of intensity was a positive $(r^2=0.8304,\;p<0.0001)$ between total phenolic contents. The total phenolic content of red wine could be estimated simply using these equations, $Y_{Total\;phenolic\;content\;(mg/L)}=3319.3-X_{Hue}/2208.36,\;and\;Y_{Total\;phenolic\;content\;(mg/L)}=1230.97-X_{intensity}/98.93$

• Korean Journal of Food Science and Technology
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• v.18 no.5
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• pp.389-392
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• 1986

To evaluate a pigment of the flower of cockscomb, Cclosia critata. as a natural food colorant, jelly-po, candy and sherbet were chosen as model foods and colorized to red with the pigment of the flower. Color changes were evaluated by analyses with Hunter color difference colorimeter. Lovibond tintometer and UV-visible spectrophotometer. Also sensory evaluation was carried out. The results obtained indicated that the red pigment of the flower had a good potential as food colorant, when it is utilized under the certain limited conditions: low water activity such as candy or low temperature. Data obtained indicated good correlation between instrumental analyses and sensory evaluation as well.

• Korean journal of food and cookery science
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• v.13 no.1
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• pp.16-22
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• 1997

This investigation was undertaken for the purpose of studying the quality and sensoryptability of Jangduck during storage containing various levels of glutinous rice flour. Composition of experiment Jangduck made with different components and contents. A standard samples of Jangduck were soybean paste : glutinous rice flour : ground beef : green onion : garlic : toasted white sesame=100 : 10 or 20 or 30 : 30 : 10 : 5 : 2 (％) and measured acceptability by 15 days. Jangduck estimated for texture characteristics through acceptability. The acceptability of Jangduck was by both objective and subjective methods. Objective measures were made utilizing the Rheometer and Hunter colorimeter. Sensory evaluated was done by a panel of 10 judges. The data analysis revealed following as for estimate of texture changes during storage by Rheometer, the hardness tended to increase as the addition level of glutinous rice flour and beef till 30 days. Hardness decreased slightly after 30 days of storage. Elasticity and cohesiveness tended to increase as the addition level of glutinous rice flour till 15 days and decreased slightly from 16 days to 60 days later By color value of Jangduck, Lightness tended to increase as the addition level of beef during storage periods. Redness tended to increased as addition level of beef before storage and decreased 15 days later. Yellowness increasde than others from days later to 15 days later as the addition level of glutinous rice flour. The result of sensory evaluation revealed that Cl [soybean paste : glutinous rice flour : ground beef : green onion : garlic : toasted white sesame=100 : 30 : 30 : 10 : 5 : 2(％)] produced the best quality in most sensory characteristics during storage.