Research on the Stability and Content Detection of Anthocyanin of Black Peanuts Clothing

摘要

The experiment determined the containment of anthocyanin from the black peanut skin and stability of the anthocyanin under different temperature, pH value, illumination conditions and different concentration of metal ions (including Cu , Mn~(2+), Mg~(2+) and Fe~(3+)). The anthocyanin was extracted under the optimum technological condition: ratio of material to liquid 1:50, 60% ethanol as extractant, extraction temperature 60°C and time 80min. The black peanut skin contains 1.03% anthocyanin, of which the absorbance decreases when pH value lowers 5.0 but rises there after and the color turns to the trend of blue gradually. Also, the closer the pH value reaches to 7.0, the better preservation rate of anthocyanin it has. Apparently, the absorbance stays at the highest level when the concentration of Mn~(2+) or Mg~(2+) is 2.00mmol/L and it rises with the concentration of Fe~(3+) or Cu~(2+) increasing. No flocculation was found to the anthocyanin by Fe~(3+).