Abstract:

Coating agents made by adding different amounts of nano SiOx into 8% bleached shellac were used for the preservation of ponkan at room temperature, and their preservation effectiveness was evaluated according to quality changes of ponkan during storage. The addition of nano SiOx improved the gas permeability and water holding ability of the films formed from it and shellac. The complex films were effective on inhibiting the respiration of ponkan, reducing the loss of water and the rot of fruit, and keeping the quality of fruit. Especially, the addition of 0.2% nano SiOx displayed the best effects on the ponkan preservation. After 60 d storage for at room temperature, the water loss of and rot rate of the treated samples were lower by 56.5% and 73.23% than those of the control samples (P ＜ 0.01), while the contents of VC, soluble solid and titratable acid higher by 1.5 times (P ＜ 0.01), 31.5% (P ＜ 0.05) and 23.53% (P ＜ 0.01), respectively.

Key words: ponkan (Citrus reticulata Blanco), nano SiOx, bleached shellac, complex preservation film, coating preservation