Determination of Anthocyanins in Whole Black Wheat Flour by pH Differential Method and Its Antioxidant Activity in Vitro

The black wheat whole wheat flour was used as raw material. According to the principle of pH differential method,the maximum absorption wavelength,buffer pH,equilibrium temperature and equilibrium time of the influencing factors were analyzed,and the pH variation method was used to determine the anthocyanin content of whole wheat flour. At the same time,the ability of in vitro scavenging free radicals(DPPH·),free radicals(·OH)and superoxide anion radicals(O₂^-·)of anthocyanin from black wheat whole wheat flour were determined. The results showed that the maximum wavelength was 531 nm.The pH values were selected to be pH1.0 and pH4.5,respectively,and the equilibrium temperature was 40℃. In the acidity environment of buffer pH1.0 and 4.5,the equilibrium time was 25 and 35 min,respectiviely. It is concluded that the anthocyanins from black wheat whole wheat flour has high in vitro antioxidant capacity,which is higher than ascorbic acid.