• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.spc1
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• pp.141-146
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• 2005

The objective of this study was to determine the characterisics of quality and antioxidant with various sweet potato(SP) varieties. The differences of skin color between general and colored SP was not significant. The flesh color of steamed SP was the lower than flesh of raw SP, and especially steamed purple SP(5.24) was lower than flesh SP(22.0). In physical characteristics, the hardness of raw SP showed the low values and the springness, gumness and hardness among steamed SP varieties was not significant. The total phenol content(TPC) of purple, yellow-fleshed and general SP had 13.1, 6.22 and 3.02 mg/g, respectively. In DPPH, the purple-fleshed SP had the highest free radical scanvering. Also, shingunmi$(88.5\%)$, Saengmi$(80.9\%)$ and Shinchunmi$(78.9\%)$ show the high antioxidant activities. The redness of SP was positively correlated with TPC in raw and steamed. However, the yellowness of flesh SP was negatively correlated with DPPH.

• Food Science and Preservation
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• v.7 no.3
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• pp.285-290
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• 2000

Color values of anthocyanins from seven natural food colorants, such as purple-fleshed sweet potato (PSP), red flower cabbage (RFC), red cabbage (RC), grape skin (GS), black rice (BR), egg plant (EP), and fig fruit (FF) were evaluated, resulting in the selection of four color sources with higher color values including PSP, RFC, RC and GS. The stabilities of anthocyanins from the selected colorant sources against metal ions, ascorbic acid, ultra-violet light, and heating were investigated. Anthocyanins from PSP and GS were degraded significantly by $Mn^{2+}$, while those from RFC and RC were degraded by $Cu^{2+}$. Asthocyanins from PSP were the most stable against the color-degrading factors, followed by RFC, RC, and GS in descending order.

• Journal of Digital Convergence
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• v.16 no.12
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• pp.593-602
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• 2018

The purpose of this study was to investigate the coloring properties of non-mordant dyes by examining local literature on silk fabric dyeing using red-colored natural dyes. Natural dyes can be prepared from the following 8 materials: purple-fleshed sweet potato, Impatiens balsamina, mulberry, fruits of Ligustrum japonicum Thunb, guava leaves, dansam, hibiscus flowers, and pruned branches of Prunus persica. To examine the surface color calculated $L^*$, $a^*$, $b^*$, ${\Delta}E^*$, and K/S value and H V/C. The variables considered in the dyeing experiment were dye concentration, dyeing temperature, dyeing time, and number of dyeing iterations, which were varied to evaluate the dyeing properties and color characteristics. As a result, the abovementioned variables, dye affinity, and red color expression were directly proportional to one another. In this study, it was found that red coloring can be obtained with natural dyes; moreover, excellent dyeing was achieved without the need for repeated dyeing or mordanting processes, which cause environmental pollution.