| Sugarcane (Saccbarum ofticinarum L.) of 態adila?cultivar were used in this study. All of the sugarcane were stored at the temperature of 21 ? ~慍 ,11 ?1 0C or 1? C. By investigating the dynamic changes of juice rate, titrated acid, total sugar, reducing sugar, sucrose. Vc.. ammo acid, respiration, phosphate, ethanol, lignin, acid and neutral sucrose invertase, acid phosphatase, ADH and PAL during the storage, the changes of quality and postharvest physiology in sugarcane were studied. Secondly, the effects of Storage State on the cane qualities and postharvest physiology were also studied. Thirdly, the changes of sucrose, reducing sugar, acid and neutral invertase in the top, middle, and bottom cane stem were detected, and the preservation techniques of peeled sugarcane were studied. The results are as follows: During the storage at 21 ?I C, the sugarcane soon showed decreased qualities and characteristics of senescence metabolism, as manifested by decreased juice rate, contents of total sugar, sucrose Nc and amino acid, increased content of titrated acid, content of reducing sugar increa~ed initially, but then dramatically decreased. Respiratory rate rose slowl:.,?during the initial 5 days, then rose rapidly and reached the maximum value at the twenty-fifth day. Contents of phosphate, ethanol and lignin increased rapidly; activities of aUd and neutral invertase, acid phosphatase, ADH and PAL rose at the beginning, but fell at the end of storage. Qualities decrease and senescence metabolism were not obvious during the storage of 150 daysat 1?C,andat 11盕C theresultswerebetweenat2l?0C andat 1? C. The storage lives of sugarcane, assessed with a standard of content of phosphate, were 20 days, about 80 days and 135 days or longer at temperature 52 ranges of 21 ?1 0C. 11 + I ~C and I ?I ~C. respectively. As a result. cold storage could retard sugarcane quality decrease and senescence effectively. Qualities of sugarcane with leaves and shoot were better than sugarcane only with shoot. Juice rates, contents of sucrose, Vc and amino acid in sugarcane with leaves and shoot were higher than in sugarcane with only shoot. Contents of titrated acid and reducing sugar were lower. Contents of phosphate, ethanol and lignin, activities of acid and neutral invertase, acid phosphatase, ADH and PAL were also lower. As a result. sugarcane stored with leaves and shoot could put off the course of stem quality decrease and senescence. Throughout the storage. content of sucrose and activity of neutral invertase were the highest in the bottom cane stem, but content of reducing sugar and activity of acid invertase were the highest in the top cane stem. Peeling and cutting stimulated the increase of respiratory rate of sugarcane by 8.43 times. The shorter me sugarcane section, the higher the respiratory rate. Changes of contents of nutrient materials, activities of neutral and acid invertases and polyphenol oxidase(PPO) in sugarcane during storage were analyzed in this study. The effects of packaging methods and preservatives on storage quality of peeled sugarcane were also evaluated. During storage, activities of invertase and PPO increased gradually, tttrated acid, ethanol and reducing sugar contents increased, while sucrose and total sugar contents decreased. Vacuum packaging with the treatment of preservative could effectively inhibit the activities of sucrose invertase and PPO, and si... |
PDF Full Text Request