Studies on the Quality of Phisio-Chemical and Fresh Keeping Technologies of Post-Harvest in Volvariella Volvacea
|School||Nanjing Agricultural College|
|Keywords||Volvariella volvacea fresh keeping irradiation MAP perforate phisio-chemical real-time quantitative PCR|
Volvariella volvacea is perishable and has a limited shelf-life, usually only 2 to 3 d at 15℃,so it is one of the most difficult storage in edible mushroom. This article used electron-beam irradiation MAP(modified atmosphere package) and modified atmosphere package films with perforated packaging method treatment with molecule level, research the phisio-chemical quality of Volvariella volvacea and found the apposite fresh keeping method in the post-harvest storage. The results of the experiments are followed:1. The fruiting bodies of Volvariella volvacea were irradiated by different dose levels of 1.0 kGy,1.5 kGy,2.0 kGy and 2.5 kGy electron-beam irradiation. They were storaged at 15℃and evaluated by sensory assessment weightlessness and hardness at different storage times. The results showed that the fruiting bodies of control which were not irradiated had higher sensory assessment which were 6 at the 4 d, but the fruiting bodies treated with different doses had lower sensory assessment which were out of edible; Hardness of all samples was falling during storage, but the samples of control had higher hardness; The fruiting bodies of control had lower weightlessness than other samples. Electron-beam irradiation at these levels did not affect in fresh keeping of Volvariella volvacea.2. Using different modified atmosphere package(MAP)films packaged the fruiting bodies of Volvariella volvacea. The results suggested that the quality of all samples were falling during storage. The fruiting bodies of control had higher sensory assessment; The weightlessness of control samples were significantly different with others which were lower; The hardness of all samples were falling during storage and the samples of control were 2-3 times higher than others; The soluble protein content were rapid descent in all samples at 24 h, but the rate of falling in samples of control was lower; The content of MDA was similar in all samples during storage and the activity of SOD、CAT had late peak value in samples of control. The results showed that MAP films package did not affect.3. The effect of modified atmosphere package films with perforated packaging method on the quality and shelf life of Volvariella volvacea during storage were investigated, compared with non-packaging. The results showed that the storage quality of non-packaging were bad than films with perforated packaging and the PVC12-6 was the best packaging method. The fruiting bodies packaged by PVC12-6 retained higher soluble protein content、activity of SOD、CAT、hardness、sensory assessment, exhibited lower MDA content、weightlessness and activity of protease. The same time the quality during storage were best and the storage time were 2-3 d longer than samples of control which storage time were only3-4 d.4. Based on the result of the third experiment, we studied the nitrogen metabolism of Volvariella volvacea in different storage time to find the best fresh keeping method. The fruiting bodies of control、PE11-6、PVC12-6 were tested in this experiment. The expression of the serine protease gene of the samples in different storage time were investigated by real-time quantitative PCR. The results showed that the relative expression of Ser gene of all samples exhibited a rapid increase at 48h, then they were continuous decrease. But the rate of decreased expression in control was lower than other samples. This result was coincidence relation with the third experiment.