Abstract:

Young rhizomes of lotus are extremely vulnerable to enzymatic browning and highly sensitive to oxygen.
Lotus rhizomes coated with chitosan were packaged in vacuum or nitrogen gas under oxygen-free conditions and then
stored at low temperatures. The degree of browning in lotus rhizomes was observed during the storage. The quality of
samples subjected to pretreatment, 2 g/100 mL chitosan coating, cling film wrapping and vacuum packaging remained
good for at least 2 months at 0–5 ℃. Enzymatic browning was a critical determinant for quality control of lotus
rhizomes during storage. Furthermore, the content of total phenolic compounds declined, PPO activity was inhibited
but not completely inactivated, relative conductivity rose, and cell membrane permeability was enhanced. All these
indicators were correlated with enzymatic browning. Vacuum packaging was more effective than nitrogen gas packaging.

Key words: lotus rhizomes, chitosan coating, browning, oxygen-free environment