Study On Starch's Application To Fresh Fruits And Vegetables Shelf-life

The fruits and vegetables yield is the first problem in the world.Because of the finity of the storage capacity and the underdevelopment of preservation technology at the room temperature,the waste and loss of the fruits and vegetables is over 38%every year.So,resolving the problem of preservation fruits at the ambient temperature is hot problem,and the edible coating is a kind of offective methods.Edible coating significantly inhibited respiration of fruits,reduced water loss, and prolonged storage days.So,it has the broad application prospect.A new and securing preserving agent was formulated with cross-linked starch as main ingredient,and added others different assistant ingredient.Tomato was studied using coating preservation at room temperature in this experiment.Through the study on effects and physiology of tomato,we could get the viable formula of starch coating preservation at room temperature.The results are showed as follows:1.Through the experiment,the effect of keeping-fresh with the different starch-based coating of the advantages and disadvantages order is:cassava starch＞potato starch＞pea starch,and the effect of preservation with 2.5%concentration of cassava starch is the best,it can inhibit respiration, reduce water loss rate,total acid and total soluble solids of fruits and vegetables.2.The test results showed that the effect of keeping-fresh with cross-linked cassava starch coating is better than the original cassava starch film,especially the high degree of cross-linked,it can effectively extend the storage of fruits and vegetables.Through the determination of water vapor trasmittance,through the oil rate,carbon dioxide transmittance and oxygen transmissibility, we can see that the performance of cross-linked cassava starch films is superior to the original cassava starch films.The higher degree of cross-linked,the starch film properties is more better.It can effectively prevent moisture loss,reduce the decompositon of complex substances and inhibit respiration of fruits and vegetables.3.Through the experiment,the best formula with cassava starch coating is:the cross-linked cassava starch 3%,the glycerine 1%,the palmitic acid 2%,the glyceryl monostearate 1%,the phytic acid 2%,β-CD 0.5%.The coating has good effect of keeping-fresh.It can keep tomato above 30 days in room temperature,and the good rate is 79%.4.The starch coating could significantly reduce water loss rate,rot rate,and significantly inhibit the respiration of fruits and vegetables.The test showed that the high respiration of tomato in 5 days with the control group.When storage 30 days,the decay rate is 95.36%,the water loss rate is 11.12%.By the starch coating,the high respiration of tomato in 20 days which extend for 15 days to the control group.When storage 30 days,the decay rate is 21.05%,the water loss rate is 8.06%.And the starch coating could significantly increase hardness of tomato,inhibit contents of Vc,the total acid and the total soluble solids,maintain good quality of fruits and vegetables,and prolong the fruits and vegetables storage time.