• Journal of the Korean Crystal Growth and Crystal Technology
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• v.33 no.5
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• pp.174-180
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• 2023

Porcelain (white ware, celadon ware) coated with a ferrous sulfate and ferrous/cobalt sulfate was sintered at 1250℃. The specimens were investigated by HR-XRD, FE-SEM, HR-EDS, and UV-vis spectrophotometer. Through X-ray rietveld quantitative analysis, quartz and mullite were found to be the main phases for white ware, and mullite and plagioclase were found to be the main phases for celadon ware. When the pigment of ferrous/cobalt sulfate was applied, were identified as an andradite phase for celadon ware and a spinel phase for the white ware, and the amorphous phase, respectively. The L^* value, which was the brightness of the specimen, was 72.01, 60.92 for white ware and celadon ware, respectively. The ferrous and ferrous/cobalt pigment coated porcelain had L^* values of 44.89, 52.27 for white ware and celadon ware, respectively; with a^* values of 2.12, 1.40, an d at b^* values of 1.45 and 13.79. As for the color of the specimens, it was found that the L^* value was greatly affected by the white ware, and the b^* value differed greatly depending on the clay. It was thought to be closely related to the production of the secondary phase such as Fe₂O₃ and andradite phase produced in the surface layer.

• Applied Biological Chemistry
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• v.47 no.4
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• pp.409-413
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• 2004

We have studied quality changes of fully ripe fruit of Korean native pumpkin 'Yangsan' regarding the following parameters: pH, sugar content, weight, water content, contents of crude protein and amino acids during 60 days storage at room temperature. As the results, there was no changes in sugar contents according to the storage period, but pH was changing to a little acidic direction with slight decrease in weight and water content. Contents of total crude proteins and comprising amino acids were increased during the storage period. The main contents of amino acids of the Korean native pumpkin, Yangsan, were glutamic acid (15.5%), aspartic acid (10.1%), lysine (8.7%), valine (7.5%), leucine (7.1%) and alanine (6.6%), which were not highly influenced during storage period. Additionally we have investigated the content of free amino acids and color changes during processing of Yangsan under high temperature at $121^{\circ}C$ and high pressure at $1\;kg/cm^2$. In fully ripe fruits, a total of 29 kinds of free amino acids were detected including 8 kinds of essential amino acids (histidine, isoleucine, leucine, lysine, phenylalanine, methionine, threonine and valine). More than 35% of total free amino acids were aspartic acid (20.3%) and asparagine (15.4%); ornithine, citrullin, and arginine, which are related to Ornithine cycle, were also detected in fully ripe fruits. But when treated with high temperature and high pressure, glutamic acid and arginine were decreased rapidly whereas ammnonium chloride was relatively increased. Moreover "b" value as yellow color indicator was decreased from 17.45 to 9.14 while treated for 60 minutes with high temperature and pressure, caused by the degradation of ${\beta}-carotene$ and other yellowish pigments in Yangsan.

• Korean Journal of Poultry Science
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• v.12 no.1
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• pp.7-16
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• 1985

Present experiment was undertaken to compare the effects of two dietary fats whose free fatty acid content was quite different on performances and on meat quality of broilers. Yellow grease or animal fat (trade name) containing 15 or 38.6% free fatty acid, respectively, was added to the broiler starter and finisher diets at levels of 3.0 and 5,0%, respectively. A total of 108, day old, male Maniker(Chunho) broiler chicks was alloted to 3 dietary treatments with 3 replications per treatment and 12 chicks per replication Though control diet was not supplemented with fat, the three dietary groups were made isocaloric and isonitrogenous. All the chicks were ad libitum fed the test diets for 8 weeks. Feed intake and body weight were measured every other week. Shank color was measured at the end of feeding trial by Roche Color Fan. To evaluate meat quality, 7 chicks of mean body weight were selected from each treatment group after the trial. Measurements were made for abdominal fat content, organoleptic scores for thigh and breast, and for contents of total lipids, free fatty acids, iodine values and peroxide values of the breasts. During the period from 0 to 4 weeks of age, the broilers fed the diets added with fats performed the same as those fed the control diet. However, the body weight gam (25%), feed intake (10.8%) and feed efficiency (11.3%) of chicks fed the fat-supplemented diets, during the finisher period (5-8 weeks), appeared significantly improved compared to those of control group (p＜0.05). During overall period of 8 weeks, body weight gain, feed intake, and feed efficiency of chicks fed the diets added with fats were, on the average, 16.2. 8.8 and 6.8%, respectively, better than, those of control Monwhile the performance between the chicks fed diets added with the two different fat sources appeared to be of the same tendency. Though the shank pigmentation was not statistically different among the treatments, the chicks fed the fat-supple ented diets tended to have slightly less pigments than the control. Organoleptic scores of thigh or breast of chicks fed the animal fat diet were of the same range as those of the other two groups. The contents of total lipids, free fatty acids, iodine values and peroxide values of breasts from broilers fed the various diets appeared to be in the same ranges among the treatments. The values for control, yellow grease and animal fat groups were 7.77, 6.66 and 6.32% for total lipids, 9.23, 9.7 and 9.31mg oleic acid/g fat for free fatty acids, 65.36, 63.89 and 59.25g/ 100g fat for iodine values, and 9.62, 10.46 and 8.79 meq/kg fat for peroxide values, respect vely. Changes of free fatty acids contents of breast during a storage for 10 da s at 4$^{\circ}C$ were also not different among the dietary groups. From the observations n. this experiment, it seems possible to conclude that the animal fat containing 38.6% free fatty acid can be used as efficiently as yellow grease in broiler diets without any adverse effects on meat quality.

• Applied Chemistry for Engineering
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• v.31 no.1
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• pp.43-48
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• 2020

Fe₂O₃ nanoparticles with the mixed structure of cubic and nanorod were synthesized by precipitation, hydrothermal, sol-gel method, etching process and heat treatment. Fe₂O₃/TiO₂ core-shell (CS) of type Fe₂O₃@TiO₂ composite was fabricated on a 20 nm nanolayer of TiO₂ coated on the surface of Fe₂O₃ nanoparticles. Fe₂O₃/TiO₂ yolk-shell (YS) composite was prepared by chemical etching and heat treatment of Fe₂O₃/TiO₂ CS nanoparticles. Physical properties of Fe₂O₃, Fe₂O₃@TiO₂ CS and Fe₂O₃@TiO₂ YS nanoparticles were characterized by FE-SEM, HR-TEM and X-ray diffraction. The solar reflectance, commission internationale de l'Elcairage (CIE) color coordinate and heat shield temperatures of Fe₂O₃, CS and YS type Fe₂O₃@TiO₂ pigments filled with poly acrylate (PA) paints were investigated by UV-Vis-NIR spectrometer and homemade heat shield temperature measuring device. The Fe₂O₃@TiO₂ YS red pigment filled PA composite exhibited excellent near infrared light reflecting performance and also reduced the heat shield temperature of 13 ℃ than that of Fe₂O₃ filled counterparts.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.9
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• pp.1325-1332
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• 2015

Lettuce (Lactuca sativa) is an important dietary leafy vegetable that is primarily consumed as a fresh or salad material. It has a number of cultural varieties with green and/or red color. Carotenoids and anthocyanins are known to be responsible for these two colors, respectively. In this study, carotenoid and anthocyanin contents were determined to evaluate the stability of these functional pigments during storage at home. Analyses were carried out at the beginning, 3, 6, 9, and 12 days after harvest. In the course of storage at room temperature, total carotenoid levels rapidly decreased, and the decrease was found to be greatest during the first 3 days. Meanwhile, carotenoid level slightly changed within the first 9 days at $4^{\circ}C$ after harvest. This result suggests that carotenoids in green lettuce are more stable when refrigerated than at room temperature. Meanwhile, total anthocyanin content in red lettuce did not significantly decrease during storage at room temperature and $4^{\circ}C$, which indicates that anthocyanins have higher stability during storage compared with carotenoids in green lettuce. Anthocyanin extract exhibited higher antioxidant activity than carotenoid extract based on 2,2'-azino-bis(3-ethylbenzothazoline-6-sulfonic acid) (ABTS) radical scavenging assay. Antioxidant activity of anthocyanin extract may also be estimated directly by the presence of another potent hydrophilic antioxidant compound, which is ascorbic acid in this extract. In addition, anthocyanin extract showed about a 5-fold higher amount of anthocyanins than carotenoids in the carotenoid extract. The high correlation between carotenoid content with ABTS radical scavenging activity indicates that ABTS assay is more suitable than 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay for detecting antioxidant capacity of carotenoid extract from lettuce.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.7
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• pp.885-891
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• 2009

To examine stability of a violet red pigment in a Salicornia herbacea L., several tests for pH, sugar, organic acid, ascorbic acid, amino acid, salt and temperature effect were carried out. A violet red pigment in Salicornia herbacea L. was the most stable in the range of pH 4 to 6. Each of the violet red pigments in Salicornia herbacea L. added with different amounts of sugar showed higher retention rate according to storage time than those of the control group. After 10 days of storage, especially the retention rate of the experimentals with 0.5 M sucrose was higher than the controls by about 11.1% while fructose, maltose, glucose and galactose were less higher in order. Also, adding organic acid reduced retention rate of the experimentals over the controls irrespective of sort and concentration of organic acid; also, the retention rate of the experiment with 0.5 M organic acid, the highest amount of all, reduced radically to 13.1 to 15.9% after 10 days storage. The retention rate of the experimentals added 1,000 ppm ascorbic acid and thio urea respectively after 10 days was 48.4%, which is higher than the controls by around 23.1%. As to amino acid, treatment on the pigment with aspartic acid 50 mM marked the highest retention rate of 41.5% and treatment with 2.0 M NaCl showed 31.6% retention rate, which was higher than the controls. While low temperature like $5^{\circ}C$ and $25^{\circ}C$ kept the stability of the pigment in storage, as temperature increased the stability of the pigment dropped rapidly.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.7
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• pp.504-509
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• 2018

The purpose of this study was to manufacture a high-performance titanium yellow pigment. Anatase type $TiO_2$ was the skeleton of the pigment and $Sb_2O_3$ is used as the color assistant for the coloring agent, $Cr_2O_3$. Mixed raw materials for the pigment were $TiO_2$(98%), $Sb_2O_3$(99.5%), and $Cr_2O_3$(99.5%). The raw materials were mixed by a dry process and crystallized by calcination at $1,000{\sim}1,200^{\circ}C$. The crystalline material was pulverized in a Jar Mill under $1{\mu}m$ by a wet process and dried for 12 hours at $100^{\circ}C$. The pigment was finally made by a fine grinding process. To determine the best temperature for calcination, 4 temperature sections ($1000^{\circ}C$, $1100^{\circ}C$, $1150^{\circ}C$, and $1200^{\circ}C$) were set up. The X-ray diffraction peak of the rutile crystalline structure was highest at $1,150^{\circ}C$. The yellow ceramic pigment, which has the rutile structure, was applied for coating materials. The synthesized pigments underwent a discoloration tests on the acid resistance, alkaline resistance, weather resistance and heat resistance. In addition, a detection test on harmful heavy metals ($Cr^{+6}$) was done. The resulting values (${\Delta}E$) of the weather resistance test (2000hr), acid resistance test, alkaline resistance test, and heat resistance test were 0.74, 0.16, 0.07 and 0.29. The resulting value for heavy metals testing was 34ppm.

• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.656-663
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• 2012

Two sorghum(Sorghum bicolor L. Moench cv. Hwanggeumchal-susu and Miryang 3) samples were milled using different milling methods, and their physicochemical properties were tested. Particle size was classified into five groups such as pin mill and low temperature-microparticulation(LTM; 10,000, 20,000, 30,000, and 40,000 rpm). The water absorption index (WAI), water solubility index(WSI), and a rapid Visco analyzer(RVA) were used to examine particle size distribution and color differences. Particle size of sorghum flour prepared using LTM was lower than that prepared using a pin mill. Particle size was further reduced by successive dry milling of the LTM flour. Lightness of colored pigments increased when particle size decreased. The WAI of Miryang 3 pin milling(M1) flour was the lowest after LTM, and WSI was higher in the order of M2, M3, M4, and M5. LTM sorghum flour had significantly higher pasting viscosity, as determined using a rapid Visco analyzer. LTM Miryang 3 sorghum flour(M2~M5) flour showed lower breakdown viscosity and higher final viscosity compared to those of M1 flour, resulting in an increased setback value.

• Applied Biological Chemistry
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• v.13 no.1
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• pp.1-27
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• 1970

The process of the forced aging of flue-cured tobacco leaves were studied extensively from various scientific points of view. The Flue-cured tobacco leaves were inoculated and fermented with nicotine resistant Hansenula yeast, or the leaves were subjected under simple forced aging. The above two processes of forced aging were studied from the summarized points of microbiology, physics, chemistry, and biochemistry, and the resulted products ware compared in their physical, chemical and biochemical quality determining factors with that of raw material tobacco leaves (dried-tobacco leaves) and 2 years aged high quality tobacco leaves. The summary results were as follows. 1) The Korean flue-cured tobacco leaves, were forcedly aged under the basic optimum aging condition, temperature $40^{\circ}C$, moisture contents 18%, relative humidity 74%. It was found that this aging condition was the best in bringing the quality of forcedly aged tobacco leaves to the utmost state. 2) Under this optimum temperature and moisture condition of forced aging in about 20 days the forcedly aged tobacco leaves both with yeast inoculation and without yeast inoculation showed the equivalent tobacco qualities comparable with that of more than 2 years aged tobacco leaves. 3) The forcedly aged tobacco leaves both with and without yeast inoculation under $40^{\circ}C$ temperature and $74^{\circ}C$ relative humidity achieved the necessary quality determining physical and chemical changes in about 20 days. 4) The microbial changes during the forced aging were as follows. The population of yeasts and bacteria increased until to 15 days of aging, then decreased thereafter. Whereas the molds grew continously until the end of fermentation. 5) The tobacco quality determing physico-chemico-properties of yeast inoculated aged and simple forcedly aged tobacco leaves, progressed as the follows in time. As the forced aging progresses, swelling and combustibility properties were improved. The pH, total reducing materials, total sugars, alkaloids contents decreased. The contents of organic and ether extractable materials increased. The total nitrogen, protein, crude fiber, ash contents showed no changes. The color properties, excitation purity, luminance, main wave length, showed equivalent changes comparable with that of 2 years aged tobacco leaves. 6) The changes in chemical components in yeast treated and simple forcedly aged tobacco leaves during $15{\sim}20{\;}days$ of forced aging were as follows. The following chemical components decreased as the aging. Sugars-sucrose. rhamnose, glucose. Pigments-chlorophyll, carotenes, xanthophyll and violax anthine. Polyphenols-rutin, chlorogenic and, coffeic acid. Organic acids-iso-butylic, crotonic, caprylic, galacturonic, tartaric, succinic, citric acid. Alkaloids-nicotine, nornicotine. The following components increased as the forced aging progressed. Sugars-frutose, maltose, raffinose. Amino acids-proline, cystine. Organic acids-formic, acetic, propionic, n-butyric, iso-valeric, n-valeric, malic, oxalic, malonic, ${\alpha}-ketoglutaric$, fumaric, glutaric acid. 7) During the forced aging of tobacco Leaves the oxygen-uptake decreased gradually. The enzyme activities of polyphenol oxidase, ${\beta}-amylase$ ${\alpha}-amylase$ decreased gradually. The activities of the enzymes, catalase, and invertase increased once then decreased at the later stage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.1
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• pp.41-50
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• 2012

The study was carried out to analyze the relationship between analysis of antioxidant activity and the level of functional components according to particle size of corn silk. Particle size was classified into 5 groups. By particle size distribution and color difference, the total phenol content and DPPH radical scavenging activity were observed. The particle sizes of corn silk were $199.17{\mu}m$, $178.27{\mu}m$, $85.48{\mu}m$, $27.4{\mu}m$ and $20.97{\mu}m$, respectively. The lightness of colored pigments was increased when the particle size was decreased. The contents of free sugar (fructose, glucose, galactose, sucrose, and maltose) of corn silk were analyzed using a HPLC. The total phenol contents by the particle sizes of corn silk were 2.01 mg/g, 2.02 mg/g, 2.06 mg/g, 2.26 mg/g and 2.26 mg/g, respectively. DPPH radical scavenging activities of samples were 21.00%, 21.75%, 22.90%, 24.35% and 23.67%, respectively. Antioxidative activities of Trolox and Fe(II) in corn silk were measured by ferric reducing antioxidant power (FRAP) assay and Trolox equivalent antioxidant capacity (TEAC) assay. TEAC values of samples were $2.36{\mu}mol$ TE / g dw, $2.81{\mu}mol$ TE / g dw, $3.20{\mu}mol$ TE / g dw, $3.36{\mu}mol$ TE / g dw, and $3.44{\mu}mol$ TE / g dw, respectively. FRAP values of samples were $11.67{\mu}mol$ Fe(II) / g dw, $12.80{\mu}mol$ Fe(II) / g dw, $13.43{\mu}mol$ Fe(II) / g dw, $13.85{\mu}mol$ Fe(II) / g dw and $15.95{\mu}mol$ Fe(II) / g dw, respectively. Total phenolic content and antioxidantive activities based on FRAP assay and TEAC assay were increased with decreasing particle size. In addition, DPPH radical scavenging activity was also increased. A significant correlation was also noted between DPPH radical scavenging activities and the content of phenolic compounds.