Tussah Silk Peptide Edible Film In The Application Of Cherry Preservation

Cherries are intolerance storage and transport.Fruit rot,stems wither and browing,fruitsoften and other phenomenon,which can occur in long time preservation.Besides,fruits arealso prone to mildew and bacterial diseases.Therefore,it is significant to study a kind ofedible films which is easy to be biodegradable,not to pollut the environment,and simple to beprepared.This is full of theoretic and practical importance for freshing fruits and vegetables.A series of researches were conducted on the utilization of tussah fibroin,including theconditions of enzymatic hydrolysis,preparation technology of edible films,the application ofedible films in freshing.The results as following:orthogonal test of3factors,3levels based onsingle factor experiments was designed according to Design-Expert7.1.6. The optimumhydrolysis conditions were:pH9.3,49℃,5000U/g.Content of alkali protease with10g/Lsubstrate mass concentration for12h,the yield of tussah fibroin peptide was31.4%.Ediblefilms mainly made from tussah fibroin peptide were studied.The effect of fibroin peptidecontent,addition of plasticizer and cross-linking agents on the films properties were studied.The effects of fibroin peptide content,addition of plasticizer and cross-linking agents,andtemperament of forming films on the film’s properties were studied.The results showed that iffibroin peptide content and addition of plasticizer were higher or lower,they weredisadvantaged for forming flims.when the addition of plasticizer rose,WVP of films roseeither,but too much to forming films;WVP reduced with the addition of cross-linking agentsrose,but transparency of films slowed down.Tempreture has some liner relationship with theproperties of films but didn’t influence WVP much.Both of the concentrations of tussahfibroin peptide and gelation are2%;Adding amount of glycerol and sorbitol is1%,and theratio of them is1:2;The content of cross-linking of glutamine transaminase is2%;Dryingtemperature is40℃.The membrance performance is better.Cherry was slected as the sample of fresh-keeping with the preferable formulation offilm-forming mixrure,placing in room tempreture and refrigerator respectively aftercoating.The ratio of weight-lossing,rot rate,respire rate, titratable acid and reducing sugarwere detected after coating.The results showed that effects of coating were significantlyobvious if cherry was storaged in room tempreture.Life activity of cherry was reduced and nutritional components were maintained well.Especially,the ratio of rot remarkably reduced32.1%.But if the environment of storage was changing constantly,the structure of films wasdestroyed.It is disadvantaged to fresh.Therefore,humidity levels influenced the properties offilms.