Study On Pachyman Treated By Ball Milling And Its Influence On The Starch Digestibility

Pachyman is isolated from Poria cocos(Poria cocos(Schw.)Wolf).It has large crystallinity,long main chain and large molecular weight,and its solubility in water is very low,so it can not be widely used,ball-milling technology is one of the effective means to prepare ultra-fine powder,the utility model has the advantages of uniform grinding,small pollution,simple operation,etc,it plays a positive role in improving the characteristics of food processing.The purpose of this thesis is micronize pachyman(MPC)by ball-milling technology to obtain the product with small particle size and high dispersion,to explore the effect of the product as dietary fiber on the digestibility of starch has great theoretical significance and practical value for controlling the digestion of star ch and the development of related functional foods.In this thesis,pachyman were extracted with water,and then the filter residue were used as raw material,the micronized pachymans(MPC)were obtained by ball-milling,their physicochemical properties were characterized,On this basis,it was blended with starch(potato starch,corn starch and rice starch)by high-speed shear method,the effects of MPC on the physicochemical properties and digestibility of starch were discussed.Screening by experimental conditions,the better ball-milling conditions of MPC were obtained,when the mass ratio of ball to material is 7:1,ball-milling treatment is carried out at the speed of 700 r/min for12 h.Under these conditions,the content of soluble polysaccharide i n MPC was0.049% ± 0.008%.With the increase of ball-milling time and rotating speed,the degree of particle breakage increases and the average particle size decreases.There are microscopic differences in the intensity of the main absorption peaks,reduced thermal stability.A variety of starch-MPC complexes were prepared by high-speed shear mixing method.The analysis of physicochemical properties of the complexes showed that,these complexes lose their original shape and have debris.X-ray diffraction showed that the crystalline structure of these starches was destroyed,and the diffraction peaks were dispersive and amorphous.Infrared spectra showed that their O-H absorption peaks changed.Thermogravimetric analysis showed that the thermal stability of the composites with MPC was improved.A series of starch-MPC complexes were prepared by high-speed shear mixing method,in vitro digestion experiment confirmed,the addition of MPC inhibited the digestion of starch,when the addition of MPC was 20%,the anti digestion effect of three kinds of starch was better.Determination of functional starch content,the results show that,when the addition of MPC was 20%,the content of resistant starch in potato starch complex increased from 63.79% to78.28%,the content of resistant starch in corn starch complex increased from65.94% to 70.72%,the content of resistant starch in rice starch complex increased from 69.96% to 78.39%.Pachyman was refined by ball-milling,their physicochemical properties have changed to some extent,it is more conducive to its combination with starch to form a complex and inhibit the digestion of starch.These results will provide technical support for the research and development of anti digestive functional starch.