• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.790-795
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• 2000

To establish the optimum conditions for the extraction of anthocyanin pigment from purple-fleshed sweet potato, a suitable extraction solvent with the optimum citric acid concentration for acidification of the solvent, and the optimum extraction time and temperature were determined. Twenty percent ethanol solution acidified with citric acid was found to be a good solvent for the extraction of the pigment from purple-fleshed sweet potato. About 10 hour extraction at room temperature was appropriate for the extraction. pH of the extract was below 3 when more than 0.7% citric acid was added. The higher the concentration of citric acid added was, the higher the total optical density (TOD) of the extract was. However, the increase in TOD of the extract was insignificant when more than 1% of citric acid was added. Therefore, addition of 1% citric acid was determined for acidification of the extracting solvent. Though the initial rate of the pigment extraction increased as the extracting temperature increased, extraction at higher temperatures of 60 or 8$0^{\circ}C$ for an extended time caused a decrease in the extraction yield due to degradation of the pigment. The optimum extraction temperature for the anthocyanin pigment from purple-fleshed sweet potato with the solvent used was determined as 4$0^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.808-811
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• 2001

Performance of pilot plant scale extraction and concentration of purple-fleshed sweet potato anthocyanin pigment was tested and the characteristics of pigment extracts and concentrates were investigated. Fifty kilograms of purple-fleshed sweet potato was extracted with 500 L of 1% citric acid in 20% ethanol. As a whole, extraction pattern of the large scale extraction was similar to that of the laboratory scale extraction. The extracted pigment solution was filtered twice with a bag filter and a winding type microfilter and the filtrate was concentrated by a large scale vacuum evaporator at $40^{\circ}C$ and 600 mmHg vac. The mean values of total optical density (TOD) of the extract and the concentrate were 6.53 and 120.45, respectively. Browning index (BI) and Degradation index (DI) of extract were 5.86 and 1.55 and those of concentrate were 5.89 and 1.56, respectively, which indicated that the pigments were not changed or degraded through the extraction and concentration process.

• Korean Journal of Food Science and Technology
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• v.7 no.1
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• pp.30-36
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• 1975

The extraction efficiency of orange-yellow pigment from the Gardenia was greatly depended upon the extraction time, extraction temperature, volume of solvent used and fat contents of the Gardenia. From the experimental results, the amounts of extracted pigment (P) was proportional to the $log\;t^{\;1{\cdot}15}$ of extraction time$(t;\;0{\sim}60\;min.)$, the $log\;T^{3{\cdot}73}$ of extraction temperature$(T;\;5{\sim}60^{\circ}C)$, the $log\;S^{3{\cdot}7}$ of volume of solvent$(S;\;5{\sim}50\;ml)$, and the -4X of fat contexts of sample $(X;\;0{\sim}0.\;15)$ at $18^{\circ}C$ for 10 minutes. Finally, the modified empirical equation was derived as follow; $P{\simeq}1.15\;log\;t+3.73\;log\;T+3.7\;log\;S-4X-6.4$ In addition to that, the most optimum conditions of pigment extraction were determined as 30 minutes of operation time, $40^{\circ}C$ of temperature. Deffated Gardenia was more productive than natural Gardenia in the pigment extraction.

• Journal of Microbiology and Biotechnology
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• v.17 no.5
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• pp.847-852
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• 2007

This study investigated an efficient method for the extraction of astaxanthin from the red yeast Xanthophyllomyces dendrorhous. The extraction process comprised three steps: 1) cultivating the yeast; 2) treating the yeast culture suspension with microwaves to destroy the cell walls and microbodies; and 3) drying the yeast and extracting the astaxanthin pigment using ethanol, methanol, acetone, or a mixture of the three as the extraction solvent. Ultimately, various treatment tests were performed to determine the conditions for optimal pigment extraction, and the total carotenoid and astaxanthin contents were quantified. A frequency of 2,450 MHz, an output of 500 watts, and irradiation time of 60 s were the most optimum conditions for yeast cell wall destruction. Furthermore, optimal pigment extraction occurred when using a cell density of 10g/l at $30^{\circ}C$ over 24 h, with a 10% volume of ethanol.

• Korean Journal of Food Science and Technology
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• v.6 no.1
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• pp.1-5
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• 1974

The extraction mode of orange-yellow pigment from Gardenia is depended upon the extraction time, extraction temperature and volume of solvent. The amounts of the extracted-pigment (C) is proportional to the log ${\theta}^{1.15}$ of extraction time $({\theta}:0{\cdots}{\cdots}{\cdots}60$ min.), the log $T^{3.73}$ of extraction temperature $(T:5{\cdots}{\cdots}{\cdots}60^{\circ}C)$ and the log $S^{3.7}$ of volume of solvent $(S:5{\cdots}{\cdots}{\cdots}50ml)$ at $18^{\circ}C$ for 10 minutes. Finally, the general emperical equation was derived as follows; C=1.15 log ${\theta}$+3.73 log T+3.7 log S-7.0

• The Korean Journal of Food And Nutrition
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• v.32 no.1
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• pp.41-49
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• 2019

Carotene, xanthophyll, carotenoid anthocyan, phycopyrine, chlorophyll, and monascus pigments are used as natural coloring agents since they are more stable to human body than synthetic coloring agents. Among them, monascus pigments are a natural red pigment produced by the Monascus purpureus. For the development of edible paint using natural pigment, Monascus purpureus strain was cultured at a temperature of $35^{\circ}C$ for 15 days on a PDYA plate and liquid medium to produce a red pigment. In addition, a large amount of the red pigment was extracted from Hongkuk Koji in parallel with water extraction and ultrasonic wave extraction. At this time, the yield of ultrasonic extract was 2~4 times higher. Thus, Monascus purpureus strains, etc. were prepared by freeze-drying powder. In conclusion, natural paints made with red pigments have enabled the development of been edible paints that can be used as eco-friendly materials with good viscosity, enhanced spread ability and coloration.

• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.149-152
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• 2001

Extraction characteristics of anthocyanin pigment from red flower cabbage(Brassica oleracea L. var. acephala) as a new source of natural food colorant were investigated. The pigment extracted from red flower cabbage showed the characteristic bathochromic shift of the maximum wavelength of light absorption(${\lambda}_{max}$) as pH of the solution changed from pH 1 to 12. As the concentration of citric acid in the extraction solvent increased, extraction rate and total optical density(TOD) of the extract increased. Maximum TOD was obtained by using the extracting solvent including $0.8{\sim}1.0%$ citric acid and stable pigment solution was obtained by using the extracting solvent including $10{\sim}20%$ ethanol in distilled water. As a result, 10% ethanolic solution with 0.8% citric acid was decided as the optimum extraction solvent for the anthocyanin pigment from red flower cabbage. Within the experimental ranges, the extraction rate increased and therefore extraction time decreased as the extraction temperature increased. The times to reach a certain value of TOD i.e., 2.1 were 24, 8, 4 and 2 hours at extraction temperature of 5, 20, 40 and $60^{\circ}C$, respectively.

• Food Science and Preservation
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• v.11 no.1
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• pp.42-46
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• 2004

Each pigments were obtained by ethyl alcohol extraction method, blue and yellow pigment from Gardenia as well as dark brown pigment from Kaoliang. Concentration of these pigments are all 60 Brix, the extraction yields were 0.68, 1.97, 0.63 ％(w/w), respectively. Oil soluble natural black pigment (OSNBP) was composed of soybean oil, water, emulsifier, Gardenia blue and yellow, Kaoliang dark brown etc. Blending ratio of these was 8: 22: 42: 10: 15: 13 (w/w), this mixture was carried out homogenized. Solubility of this OSNBP in soybean oil was appeared the maximum level at about 30∼40$^{\circ}C$ range. OSNBP solubilized black oil was not reseparated at below 20$^{\circ}C$.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.169-172
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• 2000

Studies on extraction of red pigment was performed to provide the basic information for the utilization of red pigment as s new source of natural food colorant. A bacterium isolated from marine resources were carried out the test for excretion of red pigment. One strain of a marine bacterium, KSR-97 showed a high production of red pigment on the medium of colloidal chitin, peptone-yeast extract with minerals. In physicochemical and sensory properties in aqueous solution of red pigment was investigated at various condition of pH, temperature, concentration of ethanol and stability of storage. Potent antioxidative of red pigment was separated by thin layer chromatograpy, silica gel chromatography and reverse high performance liquid chromatography using ODS hypersil column.

• 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.