| The fig tree,Ficus carica L.?Moraceae?,is one of the oldest horticultural crops.Fig has been cultivated in our country for almost one thousand years,and mainly grow in south of Xinjiang and Weihai city of Shandong province.The fig fruit has a high nutritional value,rich in sugar,vitamin,and dietary mineral and so on;besides,it is one of fruit containing the highest calcium and fiber content.Moreover,fig fruit also rich in the substances which have the physiological activator to prevention and treatment of cardiovascular disease and Alzheimer's disease,and a variety of cancer treatment.Postharvest handling and storage of fresh figs is difficult as the thin fruit skin is easily ruptured,leading to rapid loss of nutritional contents.Fig fruit can not be stored during off seasons due to their highly perishable nature and lack of appropriate postharvest technologies.Hence there is a need to improve the shelf life of fig fruit and maintain the initial fruit quality.Modified atmosphere packaging?MAP?has been widely used in a variety of fruits and vegetables with the advantages of saving the high cost of equipment and good preservation efficacy,and nano-material packaging with its strong self-cleaning ability and good sterilization ability,has the potential to be the development direction of food packaging industry.This paper was aimed to find out the appropriate modified atmosphere packaging initial gas concentration and studied the effects of modified atmosphere packaging and nano-material packaging on postharvest fig fruit,and the mechanism of prolonging shelf-life was discussed slightly.The research details and results are as follows:1.Effect of modified atmosphere packaging?MAP?on preservation quality of postharvest fig fruitThe experiment was carried out to evaluate the effects of gas composition on"Branswick" fig fruit.Postharvest fig fruit was stored for 30 days under the conditions of air temperature at 2?±1?? and relative humidity?RH?at 90?95%with the concentration of carbon dioxide was?15±0.5?%??17±0.5?%??19±0.5?%??21±0.5?%,and the concentration of oxygen was?3±0.5?%??5±0.5?%??7±0.5?%??9±0.5?%,respectively.The experimental results showed modified atmosphere packaging with?19±0.5?%CO2 and?3±0.5?%??5±0.5?%O2 could keep the fresh quality of fig fruits greatly through comparing the fig surface quality,measuring its weight loss,decay rate,hardness and color difference.Afterwards,the fig was packaged with?19±0.5?%CO2 and?3±0.5?%O2,then stored at?2±1??,RH 90?95%.Respiration rate,malondialdehyde?MDA?content,activities of catalase?CAT?and peroxidase?POD?and some nutritional quality indicators were investigated regularly.The results showed that MAP with?19±0.5?%CO2 and?3±0.5?%5±0.5%O2 could inhibited the respiration of fig,delayed the loss of nutrients such as total soluble solid,titratable acid,soluble protein,reducing sugar and ascorbic acid,controlled the increase of MDA and maintain the high activities of CAT and POD,so as to prolong the fig shelf-life.2.Effect of nano-material packaging on preservation of postharvest quality fig fruitFruit was packaged with different nano-material,and after stored at?2±1??,RH 90?95%for 20 days,the weight loss and decay rate of each group figs were analyzed.The results showed that the nano-material containing 10%Ag?5%TiO2?2.5%ZnO and 5%Kaolin was most effective in inhibiting weight loss and decay.Afterwards,the fig was modified atmosphere packaged with that nano-material and stored at the same condition above.Respiration rate,malondialdehyde?MDA?content,activities of catalase?CAT?and peroxidase?POD?and some nutritional quality indicators were investigated regularly.The results displayed that the fig packaged with nano-material showed a lower respiration rate,the less loss of fig nutrients such as total soluble solid,titratable acid,soluble protein,reducing sugar and ascorbic acid,the less increase of MDA and the high activities of CAT and POD.It indicated that the nano-material packaging could prolong fig storage period. |
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