Preparation Of Poly(ε-caprolactone)/SiO_x Film And Application Of The Film On Equilibrium Modified Atmosphere Packaging Of Cherry Tomato

This article aims to produce a film which is suitable for cherry tomato’s equilibrium modified atmosphere(EMA)packaging.It can improve the shelf life of cherry tomatoes and reduce economic losses.Meantime,this film can also reduce the pressure on environment pollution by using the biodegradable polymer as well as further expand the sales market of cherry tomatoes.At first,prepare the biodegradable films(poly(ε-caprolactone)film)by melting extrusion,then the poly(ε-caprolactone)/silicon oxide(PCL/SiOx)film was prepared by plasma enhanced chemical vapor deposition(PECVD).At last,package the cherry tomato by PCL and PCL/SiOx films.Make a perfect shelf station in accordance with the respiratory characteristics of cherry tomato and the gas permselectivity of film.The changes of physical and chemical indexes of cherry tomato during storage was tested.According to the result of FTIR picture and the SEM photo,SiOx film was deposited on the surface of PCL film.The oxygen and carbon dioxide barrier properties of PCL/SiOx film was improve 22%and 56.9%,respectively,compared with PCL film.Upon the SiOx coating,PCL/SiOx film showed appropriate gas permeability and CO2/O2 permselectivity.Although water vapor rate have changed a little various from different films,PCL/SiOx film,as sealed membrane for window packing container,was used for equilibrium modified atmosphere packaging of fresh cherry tomato.The atmosphere composition within this PCL/SiOx sealed container,which depended on the film permeability and respiration of cherry tomato,reached the steady state that 4～6%CO2 and 11～13%O2 at room temperature,and with 2～3%CO2 and 17～19%O2 at 5 ℃,respectively.High sensory score,firmness,soluble solid concentration,ascorbic acid content,lower weight loss and retarded respiration climacteric could be found for cherry tomatoes packaged by PCL/SiOx film,indicating that delayed ripening,higher nutrition content and extended shelf life could be achieved.The shelf life of PCL/SiOx packaged cherry tomatoes can last from 18 to 30 days on condition that the room temperature at 5℃.This shows that PCL/SiOx film can be used for EMAP of cherry tomatoes.