Preparation Of Potato Hydroxypropyl Enzymatic Starch And Its Application In Hollow Capsules

This thesis mainly studied potato hydroxypropyl enzymatic hydrolysis using potato starch as raw material,propylene oxide as etherification agent,pullulanase as enzymolysis agent,and hydroxypropyletherification and post-enzymatic hydrolysis.Starch and hollow capsules were tested on the prepared starch.Through the single-factor test and orthogonal test,the effects of starch concentration,Na2SO4 content,NaOH content,reaction temperature,amount of propylene oxide,and reaction time on the hydroxypropyl content of hydroxypropyl etherified starch in the preparation process were examined.The optimum preparation conditions of hydroxypropyl etherified starch.On this basis,the prepared potato hydroxypropyl starch was enzymatically modified to study the pH of enzymatic hydrolysis,the temperature of enzymatic hydrolysis,the amount of pullulanase,and the time of enzymolysis on potato hydroxypropylase.The effect of starch viscosity was determined to determine the optimum conditions for the enzymatic hydrolysis reaction.Then,using the obtained potato hydroxypropyl enzymolyzed starch to conduct a hollow capsule production test,the yield of the produced hollow capsule,the thickness of the capsule wall,the transparency of the capsule shell,the friability ratio,and the moisture content of the capsule were measured.Determine the degree of enzymatic hydrolysis of potato hydroxypropyl enzymolysis starch,the concentration of glue preparation,the temperature of tannin extract on the quality of hollow capsules.The result is as follows:(1)The optimum technological parameters for preparing potato hydroxypropyl starch by single factor and orthogonal test are as follows: starch concentration 40%,Na2SO4 content 18%,NaOH content 1.2%,reaction temperature 45°C,propylene oxide content 18%,reaction time 20 h,under the conditions obtained starch hydroxypropyl content of 5.64%.(2)The hydrolysis conditions of potato hydroxypropyl enzymolysis starch obtained by optimization of single factor experiment were as follows: the pH of enzymolysis was 5.5,the temperature of enzymolysis was 55°C,the amount of proteolysis was 1.2%,and the enzymolysis was The time is 3h.(3)Obtained through hollow capsule production experiment: When the viscosity of potato hydroxypropyl enzymolysis starch is 1600 mPa.s,the mass fraction of glue is 22%,and the temperature of tannin is 55°C,the yield of hollow capsule obtained reaches 93.7%,with moderate wall thickness,high transparency,low friability,and suitable moisture content.Studies have shown that the hydroxypropyl etherification of potato starch and the pullulanase enzymatic hydrolysis,to a large extent improved the original starch starch capsules in the process of preparation,the viscosity of the starch paste appears higher,the difficulty of silicone Large film defects,such as high film brittleness after film formation,and low finished product ratio.