Study on fresh-keeping treatment of grape by chitosan

The method of fresh keeping treatment of grape by chitosan was studied.Chitosan was used for the main agent and surfactant as additives to produce fresh keeping film, and determined the absorbance and coating effects of chitosan solution added different surfactants.In addtion, chitosan solution was used to add different metal ions to smear grape.The fresh-keeping effects were compared by determined its physiological changes in weight loss, browning index, vitamin C content and total acidity.Results showed that added Tween-20 and Calcium or Copper ions had better fresh keeping effects.The rate of weight loss and rotten fruit were reduced, the declining rate of total acid content, VC content were delayed.Chitosan added surfactant and Calcium or Copper ions had better fresh keeping effects。