| Agrocybeaegerita, a rare edible fungus, is rich in proteins, polysaccharides and mineral substances and has high nutrition value and healthy function for human body. However, because of its tender structure, high water content, it is easy to suffer from mechanical injury, and then microorganisms find the way to invade and cause it deterioration. Besides, if Agrocybeaegerita would be stored at normal temperature for a short time after harvesting, its stem would prolong and umbrella be open. Environmental conditions such as oxygen, high humidity and temperature could aggravate those changes, which could low and loss its commercial value. How to control environmental conditions, prolong shelf-life of Agrocybeaegerita and hold its nutritional value is a problem that will be settled urgently. In this dissertation, two varieties of Agrocybeaegerita were taken as experimental material. Their storage properties and effects of different fresh keeping technologies on their storage qualities were studied. The main research content and corresponding results were summarized as follows.1. Comparative analysis of the storage properties between white and brown variety of Agrocybeaegerita at different harvest period was carried out. It was concluded that at 15±1 °C, weight loss of white variety was similar to brown one. But the respiration rate, relative electric conductance, browning degree of and soluble protein in brown variety were lower than that of white one. It was obvious that brown variety was more tolerant for storage than white one. Weight loss of two varieties harvested at early stage was highest. Respiration rate of two varieties harvested at middle stage was highest, the other indices were lowest. And the change of relative electric conductance of two varieties harvested at late stage was biggest. It suggested that brown variety harvested at middle stage was suitable for storage. The indices mentioned above of two varieties stored at 5℃ were lower than that at 10 ℃. It was indicated that Agrocybeaegerita was favorite for low temperature environmental condition.2. Effect of color protection agents, viz. L-cys, EDTA-2Na, PA and CA on Agrocybeaegerita quality were observed. The results showed that the optimum combination of color protection agents was 2.5 mg·ml-1 L-cys, 0.5 mg·ml-1 EDTA-2Na, 1.0 mg·ml-1 PAand 3.0 mg·ml-1 CA. With this complex treatment, the shelf life of brown variety could reach six days at the temperature of 10 ±1℃, and its umbrella was not open, smell good, browning degree and respiration were significantly lower than that of CK.Brown and white varieties, treaded with O3 for 30 s, and then were stored at 15±1 ℃. The results showed Brown variety was more tolerant for store than white one Brown one, treaded with O3 for 30s to 2min, and then was stored at 20±1 ℃, after seven days, there was 3 % of brown Agrocybeaegerita umbrella open and its browning degree was small.Effect of PE film package with different number holes(Φ0.6 mm) on the storage quality of Agrocybeaegerita at 15±1℃ was studied. It was indicated that the PE film package with a number of hole could significantly reduce the respiration and consumption of reducing sugar of Agrocybeaegerita and its cell membrane integration was protected. Thereby, the shelf life of Agrocybeaegerita was prolonged.3. Enzymatic properties of PPO in Agrocybeaegerita was studied. It was concluded that the maximum absorbent wavelength of reaction product catalyzed by PPO was 410 nm. Optimum substrate catalyzed by PPO was L-Tyr. PPO was stable at 30℃. Optimum reaction temperature was 50℃. It was stable at pH 5.0 or 8.0. Optimum pH was 4.6 and 8.0. PPO activity in Agrocybeaegerita could be strongly inhibited by L-cys and ascorbic acid, the brown variety had two isoenzymes. White one had no isoenzymes, but had higher activity.
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