Preparation Of Whole-Component Oats Slurry By Industry-scale Microfluidizer And Its Effect On Starch Properties

Oat(Avena sativa L.),as a high-quality food and feed-in-use crop,has been planted in the world for more than 2000 years,contains a variety of important nutrients needed by human beings,and has gradually become a basic raw material for human daily diet.However,high fiber content of oat bran hinders the processing of oat food,often need to be removed to process into a variety of oat food.High-pressure micro-fluidization is an emerging physical modification technology,which has been widely used in the processing of food raw materials and food macromolecules.Based on the newly developed industry-scale microfluidizer(ISM),the whole component slurry of oat was realized under different pressure.And to study the effects of industry-scale microfluidizer(ISM)on the physicochemical properties,structure and in vitro digestibility of oat starch in whole-component oats slurry.Below are key research findings:(1)The physicochemical properties of whole-component oats slurry treated by industry-scale microfluidizer(ISM)were analyzed by Mastersizer 3000,stability analyzer and MCR3 02 rheometer,the results showed that with the increased of pressure of ISM,the particle size of oats slurry decreased obviously,the stability and the viscosity increased gradually,respectively.Compared with the samples without ISM,ISM effectively changed the state of nutrients in oats slurry.With the increased of ISM pressure,the dissolution of ?-glucan and starch in oats slurry increased,the content of fat and soluble protein increased first and then decreased,and the content of polyphenol flavonoids had with a slight downward trend,the damaged starch content gradually increased.The research results can provide a theoretical reference for the development of whole-component food by high-pressure micro-fluidization technology.(2)The effects ISM different pressures on the physicochemical properties,structure and in vitro digestive properties of oat starch(OS)in oat slurry were investigated.the results showed that starch had been gelatinized in the oat slurry treated by ISM at 120 MPa pressure.under the pressure of 0-90 MPa,with the increase of ISM treatment pressure,the moisture,protein,lipid,ash,total starch content and amylose content of oat starch did not change significantly,but the damage starch content gradually increased and the particle size gradually increased.In addition,scanning electron microscopy showed that when the treatment pressure was>60 MPa,the microscopic morphology of starch would change significantly,and the phenomenon of collapse and shrivelling would appear.The results of starch thermal properties and pasting properties show that as the pressure increased,the initial gelatinization temperature,peak gelatinization temperature,and final gelatinization temperature decreased first and then increased,the enthalpy value gradually decreased,and the peak viscosity and disintegration value increased first and then decreased.The rheological properties show that the starch treated under different pressure conditions has a typical viscoelastic weak gel structure.The gel strength of starch decreased first and then increased as the pressure increased.The freeze-thaw stability gradually weakens as the pressure increased,the drainage rate gradually increased,the solubility gradually increased,and the swelling rate has a tendency to gradually decreased,the light transmittance gradually decreased.Fourier infrared spectroscopy(FT-IR)results show that with the increased of ISM treatment pressure,the ratio of absorption peak intensity of 1047 cm-1 to 1022 cm-1 it has declined.The results of starch XRD showed that ISM treatment lead to a decrease in crystallinity.Compared with 0 MPa,60 MPa and 90 MPa were reduced by 2.85%and 3.63%,respectively.The results of starch in vitro digestion properties show that the RDS was increased,indicating that ISM treatment could accelerated the digestion rate of ISM-OS.The conclusion of this experiment can provide theoretical support for the application of high-pressure micro-fluidization modified starch and high-pressure micro-fluidization in oat starch-based products.