Study On Preparation And Application Of Table Grape Preservation Pads

Table grape is one of the characteristics fruit in Xinjiang.Long distance between Xinjiang and inland consumer market,imperfect technologies of storage and transportation as well as lagging equipment lead to a series of problems in grape preservation.Therefore,during storage and transportation,the table grapes are prone to drying,softening,threshing and rotting infected by pathogen,which result in depreciation of edible quality and commercial value.Nowadays,ecommerce has become a considerable mode of fresh grapes selling,so packing materials and specialized grape preservation are becoming essential.phyllosilicates,with its unique porous structure,can effectively absorb ethylene,thus the freshness of fruits and vegetables can be kept and their expiration can be prolonged.On the other hand,sulfur preservatives are widely used in commercial storage and transportation of table grapes due to their bacteriostatic and freshkeeping effects.But there are some problems with using sulfur preservatives,such as sulfur residue and obvious drugleft appearance in fruit package.In order to maintain the freshness of table grape,control rachis browning and reduce sulfur dioxide residue,a table grape preservation pads was designed on the basis of previous study.This pad combed sulfur dioxide preservatives and layered silicates,and had both functions of being a trademark and a fresh maintaining preservation.The table grape preservation has been applied into the study on packing and fresh maintaining of kyoho grapes,cressen grapes and shine muscat grapes.Based on the effects of the table grape preservation pad on postharvest quality,expiration,the active oxygen metabolism and rachis browning of three types of table grapes,the effective and specialized formulation were optimized.Here were three main conclusions:（1）The table grape preservation for cressen grapes in ecommerce and logistics was produced and screened.The table preservation pads can extend shelf life of cressen grapes,while table grape preservation pads T₃and table grape preservation pads T₄can reduce rotting and shattering,decrease respiration intensity and bring down ethylene production in the grape.Thus the firmness,contents of titratable acid and soluble solids and ascorbic acid of grapes can be maintained.（2）The applications of table grape preservation on fresh maintaining was carried out during transportation and storage.Different kinds of table grapes showed diverse storage characteristics in the process of transportation and storage.table grape preservation pads T₃and T₄ could reduce rotting and make sure proper sulfur dioxide residues in kyoho grapes and cressen grapes,respectively.Besides,they maintained not only the firmness of grapes,but also kept the contents of titrateble acid,soluble solids and ascorbic acid in proper amounts,reduced respiration intensity and lead to less ethylene production.So T₃and T₄ prolonged the logistics and shelf life of grapes.（3）The effects of table preservation pad’s on the active oxygen metabolism and browning of rachis were analyzed.The trend of relative conductivity and contents were:shine muscat?kyoho grapes?cressen grapes.For table grapes,the table grape preservation pads delayed the decreasing enzyme activities of catalase and ascorbic acid peroxidase,promoted the increasing enzyme activities of superoxide dismutase and peroxidase,and inhibited the increase of superoxide anion production rate,content of hydrogen peroxide and enzyme activity of polyphenol oxidease.Consequently,the senescence of grape rachis was delayed.