Study On Starch-Based Film Modified By Potato Peel Loaded With Curcumin

In recent years,the non-degradability of plastic film has led to increasingly serious global environmental pollution,which has affected people’s life and work.Therefore,the use of renewable and cheap natural resources to prepare biodegradable biopolymer-based packaging film has attracted extensive attention.Starch is a biodegradable low cost polymer.Due to its low cost,abundant resources,biodegradable and edible,starch is widely used in the food field.Potato is one of the main sources of starch and its processing activities produce a large amount of potato peels rich in starch.Therefore,in this study,starch in potato peel waste was recovered and cationic modification was carried out to prepare cationic starch.The cationic starch was identified by scanning electron microscopy,infrared spectroscopy and nuclear magnetic resonance spectroscopy.Then,a curcumin loaded cationic starch(CS)based biopolymer film plasticized by deep eutectic solvent was prepared by using cationic starch as substrate and solution casting method.The effects of various contents of curcumin on the physical properties(barrier properties,mechanical properties,water contact angle and water solubility),antioxidant activity,and release ability of curcumin in fatty food simulants of cationic starch composite films were studied.The preservation effect of the composite film on frozen chicken breast was evaluated by measuring the pH value and lipid oxidation degree of frozen chicken breast.The results showed that the surface of cationic product particles had entirely disintegrated,the pores increased,and the particle structure had been destroyed.Cationic groups were introduced into the main chain of starch,which verified that the cationic starch had been synthesized.Curcumin at low concentration was compatible with CS and was uniformly distributed in the CS matrix of the composite films.Compared with the pure cationic starch film,the incorporation of 5% curcumin increased the elongation at break(18%)and hydrogen-bonding interactions and reduced the water-vapor permeability(WVP)(21%)of the CS films.In addition,the mechanical properties of CS films were slightly improved,whereas the thermal stability of the CS films was unchanged.The CS/curcumin films showed excellent ultraviolet(UV)barrier performance and the addition of 5% of curcumin improved the UV blocking effect by 53.33%,but the transparency was slightly reduced.The antioxidant activity of the composite films was positively correlated with curcumin concentration and the highest scavenging activity of DPPH and ABTS was 86.77%and 98.09% in the composite film containing 5% curcumin.The addition of curcumin improved the antioxidant activity of cationic starch film,and curcumin could be released quickly in fatty food simulant,which reduced the lipid oxidation of packaged meat during storage,and effectively extended the shelf life of frozen chicken breast meat.In conclusion,CS/curcumin composite film is a potential food bioactive packaging material,which can not only alleviate the treatment of agricultural waste,but also has a good application prospect in the preservation of meat.