| As a high value subtropical fruit, the crop quantity of litchi in China is no.1 in the world. The ripe litchi has very special color, flavor and nutritional component. At the same time, it is very difficult to store litchi under normal condition. The color, flavor and smell of litchi will change in very short time, then litchi will lose its greenness, attraction and edible value. It was reported that about 20% litchi would loss because of rotting. The factors really restrict the long distance transportation of litchi and let most people have never taste real fresh litchi. Nowadays, lots of institutes and universities are studying on quality transformation rule and fresh-keeping technology of litchi and they have gotten some progress. But all these were major in low temperature storage, fast freeze storage and air control storage, which needs investment, equipment and land. The fresh-keeping method as talked above does not adapt to the situation of China and litchi producing area. So, this paper would concern about the physiological transformation of litchi after harvest and function of filming fresh-keeping under normal temperature. The main objective of this paper was to find a method to prolong the shelf life of litchi under normal temperature and provided some academic gist for further study. First , we studied on the physiological transformation of litchi under 5~7℃and 27~35℃, the results could help us to understand the main factors that would affect browning , rotting and shelf life of litchi. Litchi is very easy to brown, rot, go moldy and effuse juice without fresh-keeping treatment. These related to its physiological characters. The respiration rate and ethylene release was very high after harvest, especially under normal condition. PPO, AAO activities and pH would rise with the extension of time and browning. POD activities appeared to descend with the extension of time under low temperature but rose with the extension of time under normal temperature, which means that low temperature might restrain the PPO activities intensively. CAT activities, phenolic content, AA content and anthocyanogen content would descend with the extension of time and browning. The water content of pericarp would rise first and then descend if litchi was stored under low temperature, when litchi was stored under normal temperature the water would descend all along. When litchi was stored under low temperature, the relative permeability of cell membrane of pericarp is bigger than litchi that was stored under normal temperature. Therefore, the browning and water loss speed of litchi was much higher if litchi was lied under normal temperature from low temperature. At the first 7 hours, the weight loss would be 7% and the browning index could reach 4 in 24 hours. It was obvious that low temperature could break the cell membrane and affect the shelf life of litchi finally. After relativity analysis, we could find that no matter low temperature nor normal temperature, PPO activities, AAO activities and pH would have positive correlation with browning and rotting, which means that PPO and AAO accelerated browning and rotting of litchi pericarp. POD activities had negative correlation with browning and rotting under low temperature but had positive correlation with browning and rotting under normal temperature, which means low temperature might restrain the POD activities intensively. Water content, AA content, phenolic content, anthocyanogen content and CAT activities had negative correlation with browning and rotting, which means to keep the content of these substance is very important to prolong the shelf life of litchi. It is well known that the flesh and pericarp of litchi is separate. From the results of SEM we could find that there were some tiny gapes on the surface of pericarp. The pericarp was made up of three layers. The outer layer was composed of thick cell with waterproof layer. The middle layer was composed of barrier tissue and sponge tissue, which was the main part of pericarp. The inner layer was composed of several...
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