• Polymer Science and Technology
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• v.8 no.6
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• pp.721-729
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• 1997

• Applied Biological Chemistry
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• v.39 no.4
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• pp.327-331
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• 1996

This experiment was conducted to establish the efficient extraction condition for anthocyanin and tannin pigments contained in rice bran of colored rices. Efficiency of the pigment extraction was maximum when the concentration of mired solvent of methanol(3) : ethanol(7) was 70%. In purple rite(anthocyanin pigment), ‘Kilimheugmi’, 80% ethanol containing 0.5% malic acid showed the highest extraction efficiency and stability with a maximum absorbance wavelength$(\lambda_{max})$ at 538 nm. In red rice(tannin pigment), ‘Jagwangdo’, 80% ethanol containing 0.01% citric acid showed the highest extraction efficiency and stability with a maximum absorbance wavelength$(\lambda_{max})$ at 456 nm. The relative optical density of the pigments increased until the solvent temperature was reached at $70^{\circ}C$, but drastically decreased over at $90^{\circ}C$ due to color change. The higher amount of the pigment was ertracted from the longer shaking time of the solvent. Ten minutes was enough for the grinding time of rite bran in solvent. Supernatant of the pigment extractives after one day storage at $4^{\circ}C$ in dark chamber revealed higher optical density than the filtration of the pigment extractives.

• Journal of Sericultural and Entomological Science
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• v.41 no.1
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• pp.61-69
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• 1999

The dyeing experiments were done by using tannin pigments and herbs for natural fabrics such as ramie, hemp and silk. The anti-bacterial ability and color fastness were examined for dyed fabrics. Dye materials containing tannin pigment such as oak tree leaf showed rich dyeing on ramie, hemp, and silk fabrics when the pH of dye solution is lower as well as the dyeing temperature is higher. In crimson dyeing, the colour of fabric showed red-purple when the crimson pigment was extracted at 40$^{\circ}C$, while yellow-red when extracted above 70$^{\circ}C$. The colour fastness of dye materials containing tannin pigment was excellent showing 3~4 grade or above, while most of those derived from chinese medicine showed poor colour fastness of below 3 grade. The anti-bacterial ability of dye materials derived from chinese medicine was high, since the sappan wood fabric showed low bacteria reduction rate.

• Korean journal of food and cookery science
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• v.28 no.1
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• pp.17-24
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• 2012

The present study was performed to expand the application of mechanically impacting technology reported in our previous studies. Several parameters were analyzed to research Korean indigenous pigmented rice. The proximate composition of Korean indigenous rice was the following; 12.0-13.4% moisture, 74.1-77.3% carbohydrate, 6.8-8.7% crude protein, 1.68-3.25% crude lipid, 0.78-1.38% crude ash, with a 6.6-7.07 pH value. The phenolic compound content of red rice was twice that of black rice. Moreover, antioxidative activity was estimated by DPPH radical-scavenging activity (IC50 = 0.15-1.04 mg/mL). Anthocyanin and chlorophyll in each pigmented rice type were detected by spectrophotometer. Garaedduk samples were prepared with non-waxy rice, salt, 24% water, and/or 15% indigenous pigmented rice(red, green and black, w/w of total swelling non-waxy rice) and adapted with or without mechanically impacting technology. Hardness, as a main texture profile parameter of Garaedduk was maintained up to 3 days under storage at $20^{\circ}C$. The results suggest that Korean indigenous pigmented rice can be applied for functional Garaedduk adapted with mechanically impacting technology.

• Korean Journal of Food Science and Technology
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• v.40 no.2
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• pp.141-145
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• 2008

Oxidative stabilities of sesame oil prepared from black sesame flour and white sesame flour, and commercial sesame oil prepared from whole white sesame were compared by measuring oxidation induction periods, peroxide values and electron donating abilities of each oil. Oxidation induction period (12.25 hr) of sesame oil prepared from black sesame flour was longer than those (4.37 and 9.1 hr, respectively) of sesame oil from white sesame flour and commercial sesame oil. Peroxide values of sesame oil prepared from black sesame flour, sesame oil prepared from white sesame flour and commercial sesame oil were 1.3, 18.2 and 1.7 meq/kg oil, respectively. We ascertained that the oxidative stability of sesame oil prepared from black sesame flour was superior than sesame oil from white sesame flour as well as ommercial sesame oil. This was based on the fact that electron donating ability of sesame oil prepared from black sesame flour was 9% higher than that of sesame oil prepared from white sesame flour at the same concentration. The superior oxidative stability of sesame oil prepared from black sesame flour was expected, not only because only it had lignans such as sesamol and sesamolin, but also because of its brownish coloring compounds such as tannin which were not contained in white sesame flour.