Abstract: Blanching lotus sprout with 0.1% citric acid solution can significantly reduce the activity of polyphenol oxidase （PPO） in lotus root and inhibited the browning of the lotus sprout while maintaining the lotus sprout hardness. The experiments found that lotus sprout hardness decreased with the extension of blanching temperature and blanching time. The trend of PPO enzyme activity in lotus sprout was the same as that of lotus sprout. Blanching at 100 ℃ significantly reduced the lotus sprout hardness, changing the texture characteristics of lotus sprout. Experiments found that the best bleaching process was blanching at 75 ℃ for 2.5 min.

Key words: lotus sprout, citric acid, blanching, hardness, browning