Effects Of Cold Plasma Treatment On Physicochemical Properties Of Banana Starch

In this experiment,banana starch was prepared from unripe green bananas using traditional washing method,and banana starch suspension was treated with dielectric barrier discharge(DBD)plasma to get the modified banana starch.The effects of different DBD plasma power on the physicochemical properties and granular structure of banana starch were investigated,and the potential application of DBD plasma treatment as a modification method of banana starch was revealed.The experimental results shows that the physicochemical properties of banana starch changed greatly with the DBD plasma treatment intensity increasing.The solubility of banana starch sharply increased from 1.35 g/100 g to 15.05 g/100 g(55?),and its swelling power corresponding decreased significantly.The amylose content of banana starch increased sharply from 8.94 g/100 g to 55.92 g/100 g.The pasting properties of banana starch showed that the overall viscosity of the starch paste decreased significantly during the pasting process,the peak viscosity decreased from 5242 cP to 153 cP.The rheological properties of banana starch showed that the storage moduli and loss moduli of starch gelatinization system were decreased significantly in the pasting process,and its apparent viscosity decreased sharply in shear process.That also indicating that modified banana starch could formed a starch gel with lower gel strength and better fluidity.The gel texture test of banana starch also showed that the gel strength of banana starch decreased significantly.In addition,the retrogradation,transparency,acidity(pH),iodine-binding strength,freeze-thaw stability,thermodynamic properties,and in vitro digestibility of banana starch all showed a corresponding change trend with the increase of treatment intensity.With the treatment intensity increasing,DBD plasma caused a certain damage to the surface structure of banana starch granules.The increasing etching on banana starch granules caused by DBD plasma was observed by scanning electron microscope.The results of polarizing microscope showed that the modified banana starch still had typical intact granular structure.The X-ray diffraction experiment showed that the relative crystallinity of banana starch granules decreased significantly and the X-ray pattern changed slightly after treatment.FITR spectra of banana starch showed that the chemical composition of banana starch was consistent before and after treatment,and the surface short-range order of banana starch was increased.