Effect Of New Nano-antibacterial Packaging Materials On The Quality Of White Lotus Root Storage

White lotus root is one of the most popular root vegetables.The loss of commercial and economic value of the white lotus root during storage is serious due to the problem of browning.In order to maintain the quality of the white lotus root during storage,we designed a low cost and antibacterial method for the synthesis of Ag/SiO₂ antibacterial masterbatch,and prepared nano-packaging with stable antimicrobial,safe property.The white lotus root packed by nano-packaging and normal packaging was stored at room temperature（25°C,RH 35%）,and explored the mechanism of the antibacterial packaging materials to maintain the storage quality of the white lotus root.The main results of this paper are as follows:1、The strong electrostatic adsorption technique was used to change the surface charge of SiO₂ particle and drive the Ag precursor onto SiO₂ surface.The Ag particle is highly dispersed on the SiO₂ support that the Ag has higher antimicrobial property.Compared with the normal packaging materials,nano-antibacterial packaging materials can maintain the low weight loss rate of the white lotus root,inhibit the activity of white lotus root polyphenol oxidase,inhibit the browning of white lotus root,reduce the loss of nutrients,and inhibit the formation of harmful substances and maintain the quality of the white lotus root during storage.2、Samples were subjected to normal packaging or nanocomposite antibacterial packaging and then storage at 25°C and 35%relative humidity after vacuuming.The effect of the nanocomposite antibacterial packaging on the flavor quality was analyzed by electronic nose and gas chromatography-mass spectrometry（GC-MS）.The results showed that MDA and TP levels in nanocomposite antibacterial packaging were 0.8654nmol/gFW and 5.873 mg GAE/100 gDW at the end of the storage process,respectively.The activity of SOD and CAT in nanocomposite antibacterial packaging was higher than in control samples,indicating that AP inhibited the senescence of white lotus root.In addition,the nanocomposite antibacterial packaging could regulate the expression of genes related to the metabolism of volatile components in white lotus root.This study confirmed that the nanocomposite antibacterial packaging could preserve the quality of white lotus root by regulating the expression of volatile metabolism-related genes.3、To explore the effect of nano-antibacterial packaging on the respiratory metabolism of white lotus root,the content of ethanol,lactic acid,reducing sugar,respiratory intensity and the expression level of breath-related genes in the white lotus root were measured,and the content of carbon dioxide in the packaging material was studied.The results show that the nano-antibacterial packaging material has relatively low carbon dioxide content.Nano-antibacterial packaging can inhibit the formation of ethanolic lactate and inhibit the anaerobic respiration of white lotus root.Secondly,nano-antibacterial packaging can inhibit the aerobic respiration of white lotus root and regulate the genes related to respiratory metabolism expression.The antibacterial packaging material can regulate the gene expression,further affecting the quality of white lotus root.