Studies on effect of organic acids to anti-browning of Pinklady apple.

The effects of gallic acid,phytic acid,oxalic acid,citric acid and their compounds to PPO of Pinklady apple and anti-browning of the fresh and storing apple juice were studied and the safe efficient inhibitors were selected.The results showed that the inhibited rate of single organic acid to PPO was:0.2500μmol/L oxalic acid0.2000μmol/L phytic acid0.2000μmol/L citric acid and the inhibited rate was separately 94.30%,93.08%,81.31%.The inhibition effect of gallic acid to PPO was reversible.0.2000μmol/L phytic acid and 0.2500μmol/L oxalic acid could inhibit browning of fresh apple juice and the inhibition rate was separately 87.39%,85.31%.The effect of anti-browning of single organic acid was worse than that of their compounds after storing ninty days at room temperatures.0.3000μmol/L phytic acid+0.3000μmol/L oxalic acid+0.5000μmol/L citric acid had better effect to inhibit browning of fresh and storing apple juice and the browning inhibit rate were 93.19% and 90.52%.