• Food Science and Biotechnology
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• v.18 no.3
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• pp.682-688
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• 2009

Changes in lipophillic pigments concentration and its relation to color of fresh green tea liquor during heat treatment were studied. The results showed liquor greenness decreased markedly with extension of incubation time at $55^{\circ}C$, while the brightness and yellowness changed a little. Significant increase in 'a' and 'b' values of tea liquor was observed at $95^{\circ}C$. Color change of liquor at $55^{\circ}C$ was accompanied by a decrease in the level of chlorophylls, lutein and neoxanthin, and an increase in the pheophytins and ${\beta}-carotene$ levels. However, all pigments except ${\beta}-carotene$ decreased with time extension at $95^{\circ}C$. Significant correlation was found between pigments and color difference index. The browning of fresh green tea liquor was attributed to vicissitudes of lipophillic pigments during heat treatment, especially to the change of chlorophylls/pheophytins ratio. Result also showed addition of $Zn^{2+}$ at 1.6 ${\mu}mol/L$ could partially alleviate the decrease in greenness during heat treatment.

• Journal of Conservation Science
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• v.35 no.2
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• pp.153-158
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• 2019

The traditional sizing treatment for the Hanji is performed to give the following functions. Those are to stabilize the paint of the painting, to prevent the paint of painting and moisture from smearing into the painting itself, to prevent the paint of the painting and moisture from passing to the lining paper, and to make the colors of painting match the surrounding.This study analyzed a result of the effect of Hanji sizing characteristic according to glue and alum mixing ratio and applying times, affects to pigments of painting and fastness of Hanji using accelerated aging test. As a result of color measurement of sizing treated Hanji, the concentration of glue and the number of application increased, the brightness and the $L^*$ value decreased but the yellowness index increased.

• Food Engineering Progress
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• v.14 no.2
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• pp.127-134
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• 2010

This study was to develop high-nutritious energy bar from extruded hemp obtained by extrusion process. Mixture of rice flour and defatted hemp was extruded at a barrel temperature of 110 and 130$^{\circ}C$, and moisture content of 20 and 25%. Properties of extrudates such as bulk density, expansion index, breaking strength, apparent elastic modulus, water absorption index (WAI), water solubility index (WSI) have been analyzed. The antioxidant potential was determined by the DPPH-radical scavenging assay. The expansion index was the highest in rice-hemp extrudate at 130$^{\circ}C$ barrel temperature and 20% moisture content among the other hemp-added extrudates. The WAI was increased with increase in moisture content, while the WSI was increased with increase in barrel temperature. The peak viscosity of rice extrudate had higher valule than those of extrudate added with hemp. DPPH scavenging activity of rice-hemp extrudate at 130$^{\circ}C$ barrel temperature and 20% moisture content showed the highest value. Sensory properties, moisture content and color were assessed for quality of energy bar. The color values of the energy bar indicated decreasing L (lightness) and b (yellowness), and increasing a (redness) after 30 days storage at ambient condition. The highest overall acceptable was the energy bar added with rice-hemp extrudate at 130$^{\circ}C$ barrel temperature and 20% moisture content.

• Food Science and Preservation
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• v.20 no.6
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• pp.894-898
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• 2013

This study was performed to provide the basic data for the prediction of the usefulness of onion with cold tolerance cultivated in Kangwon. The physicochemical properties and antioxidant activity of freeze-dried and hot-air-dried (40 and $60^{\circ}C$) onions were investigated. The moisture content of the raw onion was 90.55%. The crude protein and crude fat contents of the freeze-dried onions were slightly higher than those of the hot-air-dried onions ($40^{\circ}C$ and $60^{\circ}C$). As for the color values, the freeze-dried onion powder was highest in lightness (77.19), and the $60^{\circ}C$ hot air-dried onion was highest in redness (6.09) and yellowness (24.60). Moreover, the color difference (${\Delta}E$) between the freeze-dried and hot-air-dried ($40^{\circ}C$ and $60^{\circ}C$) onion powders was significant. The brown index was lower in the freeze-dried onion than in both hot-air-dried onions. The total phenol content and the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging activity of both hot-air-dried onions were higher than those of the freeze-dried onion. These results indicate that the freeze-drying methods protected the physicochemical properties of the onion powder, whereas the hot-air-drying method enhanced the antioxidant activity and the total phenol content of the onion powder.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.6
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• pp.863-870
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• 2011

In this study, muffins containing Bokbunja, popularly known as a psychological activator and functional material, was made, and its preference levels and qualitative characteristics were evaluated. We measured the height and weight of muffins containing Bokbunja powder. Height decreased when the volume of Bokbunja powder increased (p<0.001). When weight was measured, there was no meaningful difference between the samples, although the Bokbunja powder-containing samples were heavier than the samples not containing Bokbunja powder. When we measured the weight and specific volume of the muffins containing Bokbunja powder, the specific volume decreased when the amount of Bokbunja powder increased (p<0.001). The moisture and pH levels of the muffins not containing Bokbunja powder were 17.04% and pH 8.59, respectively. As the volume of Bokbunja powder increased, the moisture level of Bokbunja muffin increased while the pH decreased, and there was a significant difference (p<0.001). As a result of measuring the colors of muffins, the brightness of the muffins containing Bokbunja powder decreased, and the muffins showed decreased yellowness index and increased redness. In measuring the texture of Bokbunja muffins, hardness decreased as the volume of Bokbunja power increased (p<0.001). Further, springness of the muffins decreased as the volume of Bokbunja powder increased, and there was a significant difference (p<0.001). The chewiness of the muffins not containing Bokbunja powder was higher than any other muffin sample, and there was a significant difference between the samples (p<0.001). Further, the cohesiveness of the decreased as the volume of Bokbunja powder increased (p<0.001). Bokbunja muffins showed a lower gumminess index than those not containing Bokbunja powder (p< 0.05). When the sensual qualities of the muffins were measured, the color, flavor, taste, and softness of all of the samples showed significant differences (p<0.001), and the muffins containing 8% Bokbunja powder showed the highest sensual quality indexes. When the general preference level for the muffins was measured, the muffins containing 8% Bokbunja powder showed the highest index, 7.03${\pm}$0.96. Based on this result, the ideal volume of Bokbunja powder when making muffins is 8%.

• Journal of Life Science
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• v.14 no.4
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• pp.553-559
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• 2004

To improve quality as a food source and functional properties of traditional fermented soybean paste (Doenjang), the Korean herb medicines (group I ∼ IV) extracted at 121$^{\circ}C$ for 2.5 hours were used as brine sources. Capsule Meju were fermented in cool brines with three different concentration (group A, B and C) of the extracts at room temperature for 3 months in large earthenware jars. The effect of traditional soybean Doenjang (refer as DHM below) supplemented with the extract of herb medicines on the food quality and chemical characteristics were examined. General composition of DHM (moisture 58.2%∼61.9%, pH 5.32∼5.56, total acidity 3.07∼3.70 ml, salt 11.7∼13.9%) did not differ from those of control (moisture 61.9%, pH 5.50, total acidity 3.25 ml, salt 12.6%). Concentration of reducing sugar, crude protein, crude lipid and amino type nitrogen were higher in DHM than those of control without addition of the extracts. Water insoluble-brown index showed no difference by the extracts. However, the former had higher water soluble-brown index than the latter, and within the DHM, groups I and II were higher than groups III and IV. Lightness values (L) of Hunter color index in groups I and II were 24.32 and 31.04, respectively. Redness values (a) of all DHMs were lower than that of control. Yellowness value (b) of groups III and IV were similar to that of control group, and Hunter b values of group I and II were lower than that of control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.4
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• pp.473-480
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• 2017

The aim of this study was to investigate the effects of gluten and moisture contents on the physical properties of extruded soy protein isolate. Extrusion conditions included various moisture (45, 50, and 55%) and gluten contents (20, 40, and 60%) at a fixed screw speed and die temperature of 250 rpm and $140^{\circ}C$, respectively. Specific mechanical energy input decreased as gluten content increased from 20 to 60%. Hydration ratio was highest ($293.23{\pm}13.68%$) at gluten and moisture contents of 20 and 55%, respectively. Lightness and yellowness increased as gluten content increased from 20 to 60% while redness decreased as gluten content increased. Color difference was the highest at low gluten and moisture contents. Integrity index was the highest ($71.15{\pm}0.93%$) at gluten and moisture contents of 60 and 45%, respectively. Nitrogen solubility index was not significantly affected by moisture content and was lowest ($22.46{\pm}1.11%$) at gluten and moisture contents of 60 and 55%, respectively. In conclusion, higher gluten and lower moisture contents were effective for texturization of soy protein isolate.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.3
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• pp.397-404
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• 2008

The purpose of this study was to help promote the consumption of rice by substituting rice powder for wheat flour in bread preparation and examining the effect of rice powder particle size in baked rice bread samples. Several experiments were carried to analyze and compare the quality characteristics of prepared samples of wheat flour and rice powder breads. The loaf volume index of the wheat flour bread was 6.34, and the indices of the rice powder bread samples, which were made from powder milled through 20, 35, and 45 mesh (S1, S2 and S3), were 5.37, 5.56, and 5.85, respectively. These data indicated that the loaf volume index of the rice powder bread was lower than that of the wheat flour bread, but the volume of the rice powder bread increased as the particle size of the rice powder became finer. According to texture analysis results using a rheometer, the hardness value of the wheat flour bread was $1.34{\times}10^3\;g/cm^2$, and values of S1, S2, and S3 were $1.74{\times}10^3\;g/cm^2$, $1.57{\times}10^3\;g/cm^2$, and $1.47{\times}10^3\;g/cm^2$, respectively. Therefore, S3, which was made from the finest powder among the rice powder samples, showed the lowest level of hardness. No significant differences were observed for springiness, cohesiveness, and gumminess among the bread samples. However, the wheat flour and rice powder breads had significant differences for bread crumb color. The L-value of S3(76.20) was similar to that of the wheat flour bread(77.22). but the L-values of S1(70.30) and S2(71.21) were lower than that of the wheat flour bread. In terms of redness and yellowness, the values of the rice powder breads were significantly different from those of the wheat flour bread. In terms of overall preference, the sensory evaluation results indicated that S3 was significantly the more preferred and the wheat flour bread was the least preferred among the bread samples. This study also investigated texture changes and mold occurrence in bread samples stored at $25^{\circ}C$ for 5 days. From the 3rd day of storage, bread texture became harder in all samples however, S3 showed the least level of change among the rice powder breads. The occurrence of mold began to increase abruptly from the 4th day of storage, and S2 and S3 showed mold numbers that were 2-fold greater than those of S1 and the wheat flour bread.

• Food Science and Preservation
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• v.17 no.3
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• pp.351-357
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• 2010

To decrease the intake of animal fat and cholesterol, changes in the physico-chemical characteristics of pork Boston butts cooked by different methods (boiling, steaming, baking, and frying) were investigated. Cooking weight loss and the drain rates of moisture, lipids, and cholesterol were highest during frying. The pH value increased during all cooking processes tested. The refractive index of meat fat increased markedly upon frying. The hardness, gumminess, and chewiness of meat were notably increased by frying. Springiness was not significantly affected by any cooking process, and cohesiveness was slightly increased by all cooking methods evaluated. The CIE $L^*$ (lightness) value was markedly increased upon steaming, and the CIE $a^*$ (redness) value decreased notably with boiling or steaming. The CIE $b^*$ (yellowness) value decreased slightly with either boiling or steaming, and was slightly increased when baking or frying was used. The fatty acid composition did not significantly change after cooking, except when meat was fried.

• Culinary science and hospitality research
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• v.21 no.3
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• pp.104-115
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• 2015

This study investigated the quality of muffins prepared with various concentrations of mealworm. Samples of muffins were prepared with the addition of 0, 1, 2, 4, 6 and 8% mealworm powder to the flour of basic formulation. The weight of muffins decreased as the concentration of the mealworm powder increased. The height indices of muffins containing mealworm powder were higher than that of the control. The volume index of the MW2(2%) muffin was the highest. The pH of muffins containing mealworm powder was higher than that of the control, although moisture content lower. Lightness and yellowness decreased with an increase in the mealworm powder concentration, but redness increased. No significant difference in hardness was found from increased powder concentration. The total polyphenol content and antioxidative activity measured by 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity of muffins significantly increased as the concentration of the mealworm powder increased. Muffins containing 1~8% mealworm powder had acceptable sensory properties, such as flavor, taste, and overall acceptability. The results of this study suggest that mealworm powder is a good ingredient for consumer acceptability and functionality of muffins.