Study On The Storage Of Artemisia Senlengensis By Using MAP(Modified Atmosphere Packing) With Silicon Gum Film Window

In this study, MAP with silicon gum film window(MAPW) were used to store Artemisia selengensis Turcz. The appropriate process parameters for MAPW to store Artemisia selengensis were discussed. The effect of alcohol fumigation before treatment on the storage quality of Artemisia selengensis and the mechanism that MAPW could extend the storage period of Artemisia selengensis was studied. The results were showed in the following sections:1.The effects of two kinds of packaging pouch(PE and PA) on the storage of Artemisia selengensis were studied. The results showed that O2 was depleted because of the respiration in the packing bag could not be timely added and CO2 could not be discharged in time because of the poor ventilation of PA. From the 14th days to the end of the storage of Artemisia selengensis,the O2 contentration was remained at 0.5% in PA packaging bag and the CO2 concentration was up to 49.4% in the end of storage, while Artemisia selengensis was kept in a better atmosphere because of the good ventilation of PE packing bag.At the same time,the nutrionnal indicators and physiological and biochemical changes of Artemisia selengensis during the storage were measured periodically. It was found that PE package was more effective than the PA package in inhibiting the respiration rate of Artemisia selengensis, delaying the weight loss, reducing the soluble protein and ascorbic acid content, decreasing the fiber content, maintaining a higher cellulase activity and lower pectinase activity. For modified atmosphere packaging of Artemisia selengensis, PE was a more suitable packaging material.2.In order to find a more appropriate storage method for the storage of Artemisia selengensis, MAPW and conventional MAP were compared based on PE packaging material. The results showed that compared to the conventional MAP, MAPW could maintain low respiration and maintain the water content, the soluble solids content, the soluble protein and the ascorbic acid content and keep good quality and retard the aging process and extend the shelf life of Artemisia selengensis more effectively than MAP did. Therefore MAPW was chosen as a good way to store Artemisia selengensis. On this basis, the effect of different silicon gum film window sizes(4.00cm2,6.25cm2 and 7.50cm2)on the storage of Artemisia selengensis was discussed.The results showed that the best silicon gum film window size was 6.25cm2 for the storage of 500g Artemisia selengensis in PE pouch.3.In order to improve the storage effect of MAPW,the silicon gum film window installed in different packing materials(PE and PA) and in different location of PE packing bags were analysed. The gas atmosphere,the nutrition and other indicators of physiological changes during the storage of Artemisia selengensis were measured. The more appropriate process parameters for MAPW to store Artemisia selengensis were found:PE was the more suitable packing material for MAPW and the best location of silicon gum film window was 16cm to the bottom of packing bags(The bags were 40cm×25cm).4. On the basis of the above, the effect of alcohol fumigation before treatment on the storage quality of Artemisia selengensis was studied, in the same packaging conditions, the CO2 concentration in the packing bag in which Artemisia selengensis was not fumigated by alcohol was always higher than that in the packing bag in which Artemisia selengensis was fumigated by alcohol. At the end of storage, the former is 1.68 times as high as the latter. It could be concluded that there were bacteria existing which could produce gas during the storage of Artemisia selengensis. Alcohol fumigation could restrain this kind of bacteria to some extentArtemisia selengensis without alcohol fumigation had higer total acid content than that with alcohol fumigation. It could be concluded that alcohol fumigation could restrain the bacteria surviving.5.The mechanism that MAPW could extend the storage period of Artemisia selengensis was studied. Compared with conventional MAP storage,high permeability of the silicon gum film window ensured the exchange of gas in the package with surrounding atmosphere. Cell membrane could be protected,thus the membrane system was more integrity. The activity of free radical scavenging enzymes(SOD, CAT and POD) of Artemisia selengensis stored by MAPW was apparently higher than that of control. MAPW could scavenge the free radical more effectively, so the generation and extinction mechanism of free radical could keep balance for a longer period,decreasing the hurt from free radical,the storage period of Artemisia selengensis could be extended.