• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.3
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• pp.466-470
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• 2001

Response surface methodology was used for monitoring extraction conditions, based on quality properties of old pumpkin extracts. Hunter's color L value of extracts was maximized at 101℃, 2.6 hr and decreased gradually after maximum point. The polynomial equation for Hunter's color L value showed 10% of significance level and 0.8799 of R². Hunter's color a value was minimized at 117℃, 3.9 hr and R² of polynomial equation was 0.9852 within 1% significance level. Hunter's color b value and ΔE value increased as the extracting temperature and time increased. Extraction yield of old pumpkin was maximized at 110℃, 4 hr and increased in proportional to the extracting temperature and time, but decreased after 113℃ and 2 hr. Viscosity of pumpkin extracts were maximized at 120℃, nearly 3 hr. R² of polynomial equations for yield, viscosity and sugar content were 0.9532, 0.9812 and 0.8869, respectively. Optimum ranges of extraction conditions for quality properties of old pumpkin were 102∼109℃, 2.5∼3.5 hr, respectively. Predicted values at the optimum extraction condition agreed with experimental values.

• Food Science and Preservation
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• v.20 no.4
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• pp.532-538
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• 2013

This study was done in order to monitor the quality properties of the granule using Bokbunja (Rubus coreanus Miquel) extracts. In order to prepare the granule depending on operational parameters such as content of Bokbunja extract ($X_1$, 0.4~1.2 g), sugar content ($X_2$, 6~10 g) and citric acid content ($X_3$, 0.1~0.3 g), a response surface methodology was applied to monitor the optimum recipes on the organoleptic properties and Hunter's color. The optimum recipe on the organoleptic color showed extract content of 0.96 g, sugar content of 7.05 g and citric acid content of 0.232 g. The optimum recipe on the organoleptic flavor showed extract content of 0.86 g, sugar content of 6.04 g and citric acid content of 0.215 g. The optimum recipe on the organoleptic taste showed extract content of 0.92 g, sugar content of 6.39 g and citric acid content of 0.251 g. The optimum recipe on the overall palatability showed extract content of 0.86 g, sugar content of 6.65 g and citric acid content of 0.272 g. The response surface of the Hunter's color b value was similar to the response of the overall palatability; therefore, the optimum conditions accepted by the consumers were 0.8 g Bokbunja extract content and 0.6 g sugar content in the Hunter's color a value of 6.0.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.47-52
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• 1999

Comparative effects of phosphine fumigation and gamma irradiation were evaluated on the qualities of white ginseng prepacked in a commercial laminated film in terms of water absorption, Hunter color parameters(L, a, b) and organoleptic properties(overall color/appearance, flavor) during 6 months of storage at ambient(20oC, 70% RH) and accelerated(40oC, 90% RH) conditions. Moisture content of packed white ginseng(initial 8.44%) linearly increased with storage period, thereby reaching to about 10% (r=0.9966) in ambient and more than 15%(r=0.9886) in accelerated conditions, respectively, at the 6th month of storage. The storage at severe conditions resulted in remarkable changes in Hunter's color values, decrease in whiteness(L) and increase in redness(a) and yellowness(b), while both treatments, phosphine and irradiation less than 5kGy, did not cause any significant changes in color parameters. Phosphine fumigation was shown detrimental to overall flavor of white ginseng(p<0.01), however or ganoleptic qualities of stored samples were effectively maintained by irradiation less than 5kGy(p< 0.05). As the index on the guality of white ginseng stored at severe conditions its organoleptic quality was highly correlated with moisture content(r= 0.9777) and Hunter color values(over 0.9), suggesting the critical values of 15.5% moisture and 72.56, 7.15, 21.45 in Hunter's L, a, b values, respectively.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.938-944
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• 1999

Response surface methodology (RSM) was used for monitoring the changes of Hunter's color and organoleptic colors of roasted doraji tea with variations in threonine concentration of soaking solution and roasting condition. In soaking and roasting processes based on the central composite design with variations in threonine concentration of soaking solution, roasting temperature and roasting time, coefficients of determinations $(R^{2})$ of the models were above 0.87 (p<0.05) in Hunter's color parameters and organoleptic color. Hunter's color L value of roasted doragi tea was maximized in 0.09% threonine concentration of soaking solution, $142.37^{\circ}C$ and 21.94 min in roasting condition. Hunter's color a value of roasted doragi tea was maximized in 1.24% threonine concentration of soaking solution, $154.01^{\circ}C$ and 28.59 min in roasting condition, minimized in 1.67% threonine concentration of soaking solution, $137.61^{\circ}C$ and 24.62 min in roasting condition, Hunter's color b value of roasted doragi tea was maximized in 1.10% threonine concentration of soaking solution, $154.72^{\circ}C$ and 27.12 min in roasting condition. The maximum quality of organoleptic color of roasted doragi tea was soaked in 1.25% threonine concentration, and roasted at $141.81^{\circ}C$ for 34.14 min.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.5
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• pp.735-740
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• 2014

The study investigated the roast color formation properties of ginseng upon soaking in threonine/sucrose solution followed by roasting. To determine operational parameters, including threonine concentration ($X_1$, 0.1~0.9%), sucrose concentration ($X_2$, 1.0~3.0%), and roasting temperature ($X_3$, $130{\sim}170^{\circ}C$), response surface methodology was applied to monitor color properties, including brown color intensity, Hunter's colors, and organoleptic color. Coefficients of determinations ($R^2$) of the models were above 0.8758 (P<0.05) in terms of brown color intensity and Hunter's color parameters. Brown color intensity of roasted ginseng extract was maximized in 0.70% threonine and 2.32% sucrose soaking solution under roasting conditions of 25 min at $166.03^{\circ}C$. a values of roasted ginseng were maximized in 0.74% threonine and 2.19% sucrose soaking solution under roasting conditions of $165.40^{\circ}C$. b values of roasted ginseng were maximized in 0.61% threonine and 2.28% sucrose soaking solution under roasting conditions of $159.16^{\circ}C$. The maximum organoleptic color score of roasted ginseng extract was 7.27 in 0.53% threonine and 1.01% sucrose soaking solution under roasting conditions of $146.96^{\circ}C$.

• The Korean Journal of Food And Nutrition
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• v.14 no.1
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• pp.59-64
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• 2001

Treating pork loins with lactic acid cultures (Lactococcus lactis subsp. ATCC 11454 grown in 10% milk solids) during storage at 4$^{\circ}C$ were studied. 2-Thiobarbituric acid (TBA), color. and drip loss evaluations of refrigerated pork loins were assessed. Pork loins were immersed in solutions containing 0∼10% individual lactic acid cultures for 0∼5 min. Pork loins treated with 3.96 log units of lactic acid cultures after storage of 1 days as 4$^{\circ}C$ had no significant difference (P > 0.05) TBA values compared to those of controls. Pork loins treated with 3.96 log unitss of lactic acid cultures during storage of 9 days at 4$^{\circ}C$ had no significant difference (P > 0.05). Hunter color L* and b* values compared to those of controls. However, pork loins treated with 4.10 and 4.23 log unitss of lactic acid cultures after storage of 1 and days at 4$^{\circ}C$ had a significant difference (P < 0.05) Hunter color a* values compared to those of controls. Pork loins treated with 4.10 and 4.23 log unitss of lactic acid cultures after storage of 4 days at 4$^{\circ}C$ had a significant difference (P < 0.05) drip loss values compared to those of controls.

• Korean journal of food and cookery science
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• v.2 no.1
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• pp.45-53
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• 1986

This study was conducted to investigate the effects of the properties of sugar (20％, 30%) and starch (l5％, 20%, 25％) to Angdo on Angdo Pyun's preference, texture and color_ Textural characteristics were examined through sensory evaluation, Rheometer. Color test by Color and color difference meter. The properties through sensory evaluation were appearance, color, flavor, hardness, thickness and acceptability. With Rheometer, compression force, work ratio, adhesive work and gumminess were measured. With Color and Color difference meter, L, a ana b were measured. The results were as follows: 1. Sensory evaluation indicated that with the increase of starch addition, the Angdo Pyun maintained a worse apperance and got hardened and thickened. As the amount of suger increased, the Angdo fyun maintained better in color and flavor as well as its acceptability. 2. Rheometer measurement indicated that a compression force, work ratio, adhesive work and gumminess tended to increase, as the starch proportion increased. As the amount of sugar increased, the Angdo Pyun maintained a greater adhesive work, work ratio and gumminess. 3. Color and Color difference meter indicated that figure L ana a tended to increase and b, ΔE and ΔC decrease, as the starch proportion increased. 4. In the analysis of correlation between hardness and compression force, it was found that they are highly related. In view of the above results, it came to the conclusion that Angdo Pyun with the addition of 30％ sugar and 15％ starch could give the best result among the groups studied.

• 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.

• The Korean Journal of Food And Nutrition
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• v.22 no.1
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• pp.63-68
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• 2009

Powders prepared from three different varieties Korean Ginsengs(white, red and black) are readily available ingredients and are consumed daily by many Korean as a functional food material. These variants of Ginsengs are known to exert a variety of physiological effects. Therefore, in this study, we assessed the physiochemical characteristics of Korean Ginseng Dasik prepared with different 3 types of Ginseng powder. We conducted a sensory evaluation analysis, and assessed the mechanical characteristics, Hunter's color values, and general compositions of 3 types of Korean Ginseng Dasik stored at room temperature(20$^{\circ}C$). The results of our sensory evaluation showed that there were significant differences in the color, taste and overall quality of the samples(p<0.05), but there were no significant differences in odor or texture. With regard to the mechanical properties of the samples, we noted significant differences in he Hardness, Cohesiveness, Gumminess and Chewiness of the samples(p<0.05), but no differences in springiness were detected. The luminance of the black Ginseng Dasik was significantly less than that of the red, white, and control samples(p<0.05), We noted significant differences in Hunter's b values, but no significant differences in Hunter's a values among the samples were detected. No significant differences in the general compositions of the samples were noted. In conclusion, red Ginseng Dasik among the samples evaluated herein, has the most commercial value.