• Journal of the East Asian Society of Dietary Life
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• v.25 no.4
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• pp.660-666
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• 2015

Natural food colorant are widely used to satisfy consumer preferences. Anthocyanins are red, blue and purple natural pigments. Purple-fleshed sweet potato (PSP) contains large quantities of anthocyanins. The aims of this work were i) to investigate the influence of sugars on the purple color of PSP jam and ii) to optimize the ratio of ingredients for sensory characteristics of PSP jam. Korean PSP variety "Sinjami" was used for the preparation of jam. The jams were prepared with various sugar contents (0, 20, 30, 40 and 50% total weight) consisting of steamed purple-fleshed sweet potato, water, lemon juice and apple juice. With increasing sugar contents, lightness (L) and redness (a) of PSP jams decreased while yellowness (b) increased, indicating that anthocyanins were degraded and/or brown pigments were formed due to high sugar content under heat treatment. Hardness, springiness, chewiness and cohesiveness showed significant differences among PSP jams with various sugar contents. In sensory evaluation, addition of sugar significantly increased scores for color and texture as compared to control samples. The color, texture and preference results indicate an optimal sugar content of 40% total ingredient weight for PSP jam.

• Korean Journal of Food Science and Technology
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• v.40 no.1
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• pp.76-81
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• 2008

Currently, natural food colorants and preservatives are being used for their general health benefits. Monascus koji, the product of certain fungi that grow on rice grains, has been added to many foods for coloring and preservation. In this study, the antimicrobial activities of Monascus koji ethanol extracts were investigated. Six Monascus strains (M. araneosus KFRI 00371, M. kaoliang ATCC 46597, M. pilosus IFO 4520, M. purpureus IFO 4482, M. ruber IFO 32318 and M. sp. ATCC 16437) were selected based on their relative intensity of red pigment. Two Monascus extracts, M. kaoliang ATCC 46597 and M. purpureus IFO 4482, displayed antimicrobial activities against Bacillus subtilis, B. cereus, Micrococcus luteus, Staphylococcus aureus and Salmonella typhimurium in concentration-dependent manners. The two extracts showed their strongest antimicrobial activity against S. typhimurium, a cause of food poisoning. Therefore, these results suggest that Monascus koji could be used as a natural food colorant and preservative.

• Food Science and Preservation
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• v.16 no.3
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• pp.400-404
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• 2009

With the aim of using Bokbunja byproducts as natural pigments, characteristics of extracts were investigated after application of different extraction conditions. Total optical density (TOD) of pigment extracts was greatest (9.51 units) when 80% (v/v) ethanol was used as solvent. The polyphenol content was greatest when 40% (v/v) ethanol was used and tended to decrease with higher concentrations of ethanol. The TOD values were increased when citric or lactic acid was added to extracting solvents. Polyphenols were effectively extracted by solvent containing ascorbic acid. As the level of byproducts increased with different extraction procedures, TOD and polyphenol content of byproducts tended to decrease. More than 90% of anthocyanin pigments and polyphenols could be obtained using two extractions with 40% (v/v) ethanol.

• 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.

• Korean Journal of Medicinal Crop Science
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• v.12 no.3
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• pp.262-265
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• 2004

Gardeniae Fructus (Gardenia jasmmoides Ellis) is widely used as a natural food colorant and as a traditional medicine for the treatment of hepatic and inflammatory diseases. The quality evaluation of Gardeniae Fructus was carried out by HPLC using geniposide as a marker. The geniposide was isolated from commercial Gardeniae Fructus on ODS column using a mixed solvent of acetonitrile-water (v/v 9:91) as mobile phase and a detection wavelength 240 mm. The content of geniposides in twenty different samples was in a range of 1.20% to 7.17% of total tissues and the average was 4.97%.

• Nutrition Research and Practice
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• v.2 no.1
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• pp.46-49
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• 2008

Anthocyanin pigments from varieties of black, red and wild rice were identified and quantified to evaluate their potential as nutritional function, natural colorants or functional food ingredients. Anthocyanin extraction was conducted with acidified methanol with 0.1M HCl (85:15, v/v) and identification of anthocyanin, aglycone and sugar moieties was conducted by comparison with purified standards by HPLC, Ultraviolet-Visible absorption spectrophotometer and paper chromatography. Black and wild rice showed three different types of pigments by HPLC whereas red rice variety did not show any anthocyanins. Out of three pigments detected, one (peak 2) was characterized as cyanidin-3-glucoside (C3G) by comparison of spectroscopic and chromatographic properties with an authentic standard, and another (peak 3) was tentatively identified as cyanidin-fructoside on the basis of spectroscopic properties with ${\lambda}_{max}$ of aglycone in 1% HCl methanol at 537 nm, electrospray ionization mass spectra with major ions at 449 and 287 m/z and chromatographic properties. But another pigment (peak 1) has not been characterized. The most abundant anthocyanin in black and wild rice was C3G.

• Food Science of Animal Resources
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• v.30 no.6
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• pp.1014-1023
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• 2010

This study was performed to evaluate the quality characteristics of low-fat boiled or smoked sausages containing sodium nitrite and various levels of red beet during refrigerated storage. Physicochemical properties of boiled and smoked sausages were not affected by the addition of red beet (p>0.05), except for the color values. The interaction between treatment and storage time had significant effects on redness and yellowness of boiled sausages, and on redness of smoked sausages (p<0.05). Boiled sausages containing more than 0.5% red beet decreased lightness and increased redness and yellowness (p<0.05). During storage time, redness decreased and yellowness increased (p<0.05). The combination of sodium nitrite with red beet was better than red beet alone for color stability. In the smoked sausages, addition of red beet decreased lightness, but redness (p<0.05), unlike the boiled sausages, did not change. Redness of sausages containing red beet alone decreased with increased storage time (p<0.05), but there was no change (p>0.05) upon treatment with the combination of sodium nitrite and red beet. These results indicate that the combination of red beet and sodium nitrite contributed to color stability of smoked sausages during refrigerated storage. Therefore, we suggest that red beet as a natural colorant may be used to reduce the content of nitrite during low-fat sausage processing.

• Korean Journal of Food Science and Technology
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• v.50 no.1
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• pp.21-27
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• 2018

Turmeric oleoresin, extracted from the rhizome of Curcuma longa L., is a widely-used natural food colorant. Curcuminoids, the major pigments in turmeric, which include curcumin, demethoxycurcumin (DMC), and bisdemethoxycurcumin (BMC), possess various physiological activities. In the present study, changes in the chemical properties, antioxidant activities, and cytotoxicity of turmeric pigments upon heating were investigated. Color intensity of turmeric was significantly reduced after heating. Residual levels of curcumin, DMC, and BMC after 15 min of heating at $95^{\circ}C$ were 11.9, 37.4, and 77.3% respectively. Scavenging activities of turmeric against 2,2'-azobis-3-ethyl-benz-thiazoline-6-sulfonic acid (ABTS), 2,2-azobis (2-amidinopropane) hydrochloride (AAPH) peroxyl radicals, and nitrite were significantly enhanced after heating, while 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging activity remained unaffected. Generation of $H_2O_2$ from turmeric was increased via thermal decomposition. Cytotoxicity of turmeric pigments against colon cancer and normal intestinal cells was reduced significantly after heating. The results indicate that thermal processing affects chemical properties and bioactivities of turmeric pigments. These effects should be considered during the processing of foods containing turmeric pigments.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.218-222
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• 1997

Twelve varieties of yellow sweet potatoes were measured for carotenoids content to assess their potential as a source of natural food colorant. Benihayato variety had the highest content of carotenoids (20.2 mg/100 g fr wt) but other varieties ranged with $4.6{\sim}16.7\;mg/100\;g$ fr wt. Hunter's +a-values (redness) increased linearly $(R^{2}=0.826)$ with carotenoids content of yellow sweet potatoes. Absorption spectrum of carotenoids extracted from the Benihayato variety was similar to that of standard ${\beta}-carotene$ indicating that carotenoids in yellow sweet potato are mostly composed of ${\beta}-carotene$.

• Korean Journal of Food Science and Technology
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• v.21 no.3
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• pp.446-452
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• 1989

The pigment of the Korean cockscomb flower, a betacyanin, was evaluated for its stability in terms of temperature, pH, and its behavior upon exposure to water, light, and air. The pigment was the most stable at pH 4.0, and its activation energy (Ea) for degradation was shown to be 17.55Kcal/mol. In general, sugars protected against color degradation at the concentration of 0.1M. Degradation of this pigment in the presence of food constituents, such as organic acids , metal ions, or antioxidants, at the concentrations normally present in food preparations, can be kept to a minimum by selective adjustment of conditions. This pigment, therefore, has potential value as a food colorant under selected conditions.