This research verified the usefulness and practicality of citrus peel extract as a natural dye. This study dyed cotton, silk, and cotton/mulberry fiber blended fabrics using citrus peel extract, and measured the dyeability and functional property to verify their usefulness and practicality. The dyeing affinity of the citrus peel extract was measured by dyeing under alkaline conditions to determine the temperature and time for optimal dyeing conditions of the solution. The results show that a temperature and time of 60℃ and 30 minutes were optimal for dyeing cotton fabrics with citrus peel extract, 50℃ and 60 minutes for silk fabrics, and 60℃ and 60 minutes for cotton/mulberry fiber blended fabrics, respectively. In addition the results of measuring the color fastness of the cotton, silk, and cotton/mulberry fiber blended fabrics dyed with the citrus peel extract show that the color fastness was superior for washing, friction, sweat, and water. However, the color fastness for sunlight appeared to be slightly weak. In addition, it was found that fabric dyed with the citrus peel extract showed partial antimicrobial properties. The antimicrobial property appeared the greatest in the silk fabric. The cotton/mulberry fiber blended fabrics had 90% or more Staphylococcus aureus present, but the antimicrobial properties were not high in the cotton fabric. Additionally, the heavy metal content, which is harmful to the human body, appeared to be lower than standard figures, so the dye was found to be innocuous to humans. Therefore, when the results of this study are put together, citrus peel extract is sufficiently useful and practical as an ingredient for a natural dye. Moreover, there is ample possibility to develop citrus peel dyed fabrics as environmentally friendly fashion materials.

본 연구는 피복물질로 말토덱스트린을 이용하여 미세캡슐화 공정을 코치닐색소와 녹차추출물에 적용하였을 때 각각의 기능성으로서 색도 및 DPPH radical 소거활성의 향상정도를 비교 분석하고자 하였다. 코치닐색소와 녹차추출물의 미세캡슐화 전과 후의 입자크기를 비교하여보면 평균 직경은 각각 127.50에서 45.5 μm, 274.90에서 5.48 μm로 작아졌으며 비표면적은 0.068에서 0.850 m2/g, 0.025에서 1.226 m2/g으로 증가하였다. 코치닐색소의 a값은 미세캡슐화 전의 27.76에서 후에는 48.96으로 증가하였으며 b값 또한 13.78에서 27.92로 크게 증가하였다. 녹차추출물의 미세캡슐화 전과 후의 DPPH radical 소거활성을 비교하여보면 23.59에서 31.03%로 증가하였으며 5%내에서 유의성차이를 보였다.

The purpose of this study was to perform a functional components analysis and investigate the physical properties of powders made from the stems or fruit of freeze-dried Cheonnyuncho cactus (Opuntia humifusa). The functional components analysis showed that the stem and fruit powders han vitamin C levels of 42.14 mg and 105.21 mg, respectively. The stems powder contained more lutein than the fruit powder. The fruit powder contained more vitamin C than the stem powder. The SDF (soluble dietary fiber) and IDF (insoluble dietary fiber) in the stem powder were 45.24% and 22.15%, respectively, which were higher then the values for the fruit powder. The stem and fruit powders contained 19.30 mg/g and 25.10 mg/g of crude saponin, respectively. The pH of the stem and fruit powders was 5.34 and 5.07, respectively, both indicating low acidity. The L, a and b values of the stem powder color were 78.28, –3.71, and 19.19, respectively. The L, a and b values of the fruit powder color were 55.56, 24.84, and –3.18, respectively. The stems powder had a higher bulk density, water holding capacity, and swelling power than those of the fruit powder, but water-retaining capacity of the stem powder was lower than that of the fruit powder. In addition, the stems powder had a higher viscous material content and water uptake compared to the fruit powder. Based on the above results, we determined that Cheonnyuncho (Opuntia humifusa) powder had potentially useful functional components and physical properties.