• 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.

• Food Science and Preservation
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• v.8 no.1
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• pp.102-108
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• 2001

Flow properties of the concentrated pigment solutions extracted from purple-fleshed sweet potatoes were determined using a cone and plate rotational viscometer for soluble solids concentration range of 25 to 65% at temperature range of 20 to 60 $^{\circ}C$. The purple-fleshed sweet potato pigment solutions exhibited Newtonian behavior. Temperature dependency for the viscosity of the solution followed the Arhenius relationship with activation energy values between 14.23 and 43.00 kJ/mol, which increased linearly with soluble solids concentration. A relationship between viscosity, temperature and soluble solids concentration was investigated. At the same temperature, the viscosity of the concentrated pigment solutions increased exponentially as the concentration increased with higher degree of such phenomena at lower temperatures.

• Applied Biological Chemistry
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• v.41 no.3
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• pp.213-218
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• 1998

A bacterium with potent activity of pigment production and protease was isolated and identified as being Bacillus sp. CS-17. Cell growth, protease activity and pigment production of the strain reached to its maximum point after 24 hrs, 48 hrs, 72 hrs, respectively. The best pigment producing ability of Bacillus sp. CS-17 was shown on basal medium for pigment production added 1.0% soybean. The high effcient conditions for pigment production was obtained at culture of pH 8.5, $37^{\circ}C$ and 72 hours. Among the tested 5 gram positive strains and 6 gram negative strains, weak antibacterial activity of pigment concentrated extracts was appeared against growth of B. subtilis, P. aeruginosa, S. typhimurium, E. aerogenes, B. cereus, A. hydrophila.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.492-496
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• 1997

Purple sweet potato pigment extract was concentrated using both membrane separation method and vacuum concentration method. The pigment extract (anthocyanin content 1.6 g/L) was concentrated $({\times}25)$ after 5 hr of continuous operation of a nanofiltration to get anthocyanin content of 10.6 g/L. Total solid content also increased continuously while the flux decreased continuously during the concentration process. Degradation index (DI) changes of concentrated pigment solution were insignificant during the whole concentration process which is indicating that the nanofiltration method does not affect color degradation of anthocyanin pigment. For the comparison test, the same pigment extract was concentrated using a rotary vacuum evaporator at temperatures of 40 and $60^{\circ}C$. At both temperatures, pigment content increased in a similar manner during concentration $({\times}5)$. However, DI value at $60^{\circ}C$ increased while that at $40^{\circ}C$ did not change appreciably. Total color difference value changed only slightly by nanofiltration and $40^{\circ}C$ while changed significantly by $60^{\circ}C$. These indicate that a membrane filtration method is more effective in concentrating purple sweet potato pigment extract than a vacuum concentration method by high temperature.

• Korean Journal of Food Science and Technology
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• v.34 no.2
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• pp.238-243
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• 2002

The effects of concentration and temperature on degradation of anthocyanins of purple-fleshed sweet potato pigment concentrate and a Japanese plum juice were determined over temperature ranges of 60 to $90^{\circ}C$ and 5 to $60^{\circ}C$, respectively. Degradation of anthocyanins in pigment concentrates followed the first-order reaction rate. Activation energies of the pigment solutions ranged 51.29-73.02 kJ/mol, linearly decreasing as concentration increased except the pigment solution of $8.4^{\circ}Brix$ which was not concentrated after extraction. Anthocynins in Japanese plum juice was also degraded by the first-order reaction kinetics with activation energy of 75.80 kJ/mol. Storage life of the beverage was extended with decreasing storage temperature. Pigment was ratained more than 80% until 8 months storage at $5^{\circ}C$.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.1
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• pp.44-54
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• 2016

This study compared the physicochemical characteristics, proximate composition, taste compounds, and antioxidant properties of Sikhye prepared with mulberry fruit concentrate. Analysis of the physicochemical characteristics of Sikhye added with mulberry indicated that sugar content and titratable acidity increased significantly with increasing mulberry concentration, whereas pH decreased significantly. The whiteness index (L) was 36.77~51.40, which significantly decreased with increasing mulberry concentrate. The redness index (a) was -0.90~1.97 and highest in Sikhye sample containing 4% mulberry concentrate. The yellow index (b) was 0.03~1.90 and highest in Sikhye sample containing 1% mulberry concentrate. Analysis of the antioxidant properties of Sikhye added with mulberry indicated that total polyphenol content and flavonoid content increased significantly as the amount of mulberry concentrate increased above 1%. Total anthocyanin color also increased significantly with increasing mulberry concentrate. The mulberry Sikhye sample containing 8% extract showed the strongest antioxidant properties based on DPPH radical scavenging activity, reducing power, and FRAP assay. Evaluation of the sensory properties of Sikhye added with mulberry revealed that the most preferred flavor, color, and taste were observed in Sikhye samples containing 2%, 4%, and 8% extract, respectively. However, the highest overall preference was observed in Sikhye sample containing 2% extract, indicating that 2% concentration was most suitable for Sikhye and that flavor and aftertaste were more critical than taste. Analysis of the storage characteristics of Sikhye added with mulberry indicated that total bacteria count increased across all samples with increased storage period. However, total bacteria count in the added mulberry concentration group decreased in comparison to the control group as the amount of added mulberry increased.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.407-410
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• 1993

Stability of the anthocyanin pigment isolated from 'Comet' radish was decreased with increase of pH from 1.0 to 8.0. The destruction rate of anthocyanin at early stage was faster at pH 1.0 than pH 2.0 and 3.0, increased with increase of storage temperature from $0^{\circ}C\;to\;40^{\circ}C$. Thus the pigment preservability at $0^{\circ}C\;and\;40^{\circ}C$ after 10 days was 92.5% and 48.1%, and the half life at $0^{\circ}C\;and\;40^{\circ}C$ was 94.9 and 12.1 days, respectively Pigment was decreased with increase of ascorbic acid content from 0.015g to 0.05g.

• Food Science and Preservation
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• v.17 no.6
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• pp.847-852
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• 2010

The anthocyanin pigment composition and color of several grape cultivars including Campbell Early, Muscat Bailey A, Kyoho (black berries), and North Red (red berries), were investigated. Twelve types of anthocyanins were identified in these cultivars by LC-MS. Black-colored cultivars, especially Muscat Bailey A, contained the widest range of anthocyanins, whereas the anthocyanin composition of North Red, the red-colored cultivar, was relatively simple. Anthocyanins extracted from the skin of berries were red in color at low pH, regardless of the origin of the extract. At higher pH, however, various colors, including blue, violet, brown, and black, were evident, depending on the cultivar. Differences in color expression among cultivars may be related to variations in the types and amounts of anthocyanidins synthesized, from which anthocyanin pigments are derived. The colors expressed by anthocyanin pigments were strong and diverse even at low concentrations. Therefore, anthocyanins extracted from grapes may be useful as natural food colorants.

• Korean Journal of Food Science and Technology
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• v.12 no.4
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• pp.305-312
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• 1980

Studies have been carried out on the structure and the content of the anthocyanins in elderberries which were just recently transplanted in Korea. The anthocyanin pigments of elderberries were extracted with 1 % methanolic HCl and purified with Amberlite IRC-50 cation exchange column. The individual pigments were isolated by paper chromatography. Five pigments, identified by various chemical and physical methods were cyanidin-3-monoglucoside(4.3%), cyanidin-3,5-diglucoside(28.3%), cyanidin-3,5-diglucoside with p-coumaric arid(12.9%), cyanidin-3-xyloglucoside-5-glucoside(38.3%), cyanidin-3-xyloglucoside-5-glucoside with p-coumaric acid(16.2%). The content of total anthocyanin in elderberry was 3.13 mg/g fresh weight.

• Korean Journal of Food Science and Technology
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• v.43 no.2
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• pp.240-242
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• 2011

In this study, liquid culture of Tricholoma matsutake mycelia was performed via biomass production, and its inhibitory effects on melanin biosynthesis were evaluated. The Tricholoma matsutake mycelia extract inhibited 38.6% of tyrosinase activity at 100 ppm, which is higher than that of extracelluar medium at same dose. In addition, when 100 ppm of Tricholoma matsutake mycelia extract was treated to melan-a cells for 3 days, 19% of melanin production was reduced without cell toxicity. These results suggested that cultured Tricholoma matsutake mycelia might be useful as a skin depigmenting material.