 Wysłany: Śro 0:53, 30 Mar 2011 Temat postu: Orange peel pigment extraction and stability _1057 |
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| Orange peel pigment extraction and stability
Solution in the UV light irradiation at different times, measuring the absorbance, and the results shown in Table 2.278 NORMAL UNIVERSITY (NATURAL SCIENCE) Table 2 under ultraviolet light absorbance of pigment placed under natural light at room temperature at different times, measuring the absorbance degree, the results shown in Table 3. Table 3 under natural light irradiation effects on the pigment data can be seen from the above Time/d0136810150.8850.8830.8690.8360.8320.8360.842, orange skin pigment is stable in ultraviolet light; room temperature for long periods under natural light but also There was no significant change; the pigments and good light. 2.4 Thermal stability of the pigment (see Table 4) Table 4 at different temperatures and different time absorbance data can be seen from the table, orange skin pigment stability. 2.5pH value of (see Table 5) Table 5, the absorbance values of different oH can be seen from Table 5, acid decreased, the absorbance decreases gradually; but the pigment is stable under acidic conditions. In the pH = 12, I suddenly increased, visual solution (from acid to alkaline) color was deepened from pale yellow to bright yellow, indicating the strong alkaline, changes in the nature of the pigment. In the pH to 12, become darker in color, may form a strong base of new products and pigments. 2.6 oxidants, reducing agents on the pigment of Table 6-oxidants, reducing agents on the pigment H2o2/mL, N · 2s03/g51O150.050.250.5A0.0660.0810.0820.0290.0290.031 from the table 6 can be seen that the pigment have a certain resistance to oxidation resistance, reducing capacity, visual color of the solution, plus Na. SOs to the color lighter, add H. O. After almost no color change, the pigments resistant to reduction than the oxidation resistance ability. 2.7 the impact of metal ions on the pigment concentration of metal ions on pigment stability of results included in Table 7. Data can be seen from Table 7, the addition of various ions on the absorbance of the pigment has a certain influence, in which shaking Cu, Mn shaking, Fe shaking, Mg. + Greater impact, there may be complex formation. Especially when Fe. + Concentration of 500 × 10mol / L, the absorbance changes in the larger, lighter color visual solution. Note, Fe + in a very dilute solution because of their absorption in this wavelength, leaving the absorbance increases. In short, the pigment from the interference of multiple metal resistance ability. Table 7 gold and one ion of the pigment stability 00.4780.4780.4780.4780.4780.4782O × 10 a 0.4470.4450.4550.4560.4550.4331100 × 10 a 0.4680.5000.4670 .4630.4560.501500 × 10 a 0.4630.4910.4680.4690.4930.5962.8 pectin analysis using acid hydrolysis, extraction and alcohol precipitation of pectin, extracts of 1.5 ~ 2. between 0, the temperature in the range of 40 ~ 100 ℃, extraction 1 ~ 2h [4], the yield of pectin can reach 18.1. 3 Conclusions (1) orange skin pigment soluble in acid solution,belstaff outlet, water, methanol, ethanol, ether and other liquid substances, do not dissolve in cooking oil. (2) Orange peel pigment in the pH range of 2 to 6, and its stability is good, basically do not change color, but when the pH is alkaline, and its stability was reduced; pigment has strong resistance to light and heat sexual; shaking metal ions Cu, Ca shaking, Mn shaking, Na +, Mg. + The role of the pigment was not significant, but a greater impact on the pigment Fe ¨; orange skin pigment on H. O. Resistance to oxidation compared with Na: SOs and strong resistance to reduction. (3) orange skin color can be extracted not only bright, good stability and a natural pigment, but also can use it to extract the pectin and realize the comprehensive utilization of orange skin, is a worthy development of natural resources. |
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