Studies On The Properties Of Starch From Germinated Polished-rice-with-germ

Golished-rice-with-germ is used as the raw material. The mechanism of germination ,the physical and chemical characteristics of starch and the Molecule Characteristics of Starch from germinated polished–rice–with–germ (GPRG), brown rice,germinated brown rice and polished-rice-with-germ(PRG) as the comparison. The aim is to change the characteristics of PRG by germination.It provides technological foundation for the further development and utilization of rice resource The main conclusions are as follows:A study was made on water–absorbing curve of PRG and brown rice in the soaked temperature 25℃, Inspecting the various of enzyme activity and the content of composition by the time single factor test in the process of germination of PRG and brown rice.The results show that:The water–absorbing curve of Polished-rice-with-germ and brown rice presented the same tendency,both of them could absorb a large mount of water and achieve the saturated concentration in eight hour, the PRG began to absorb water earlier and the speed of water absorption rapider than brown rice; The activities ofα–Amylase andβ–Amylase increased during and following germination; The activity of Endoglucanase increased during and following germination; The results showed that total and reductive sugar increased and then decreased during the germination development;The content of total and reductive sugar in PRG higher than brown rice during and following germination; The conlent of starch decreased during the germination development ,but the content of Amylose Having Hot-water Solubility increased continuously along with germination.The physical and chemical characteristics of starch from germinated polished– rice– with– germ (GPRG) were studied with brown rice, germinated brown rice and polished– rice– with– germ as the comparison. Results show that the amylose content of GPRG decreased. The swelling power, solubility, transmittance of GPRG increased and freezing-thawing stability of GPRG was improved. The peak viscosity and breakdown of starch of GPRG decreased; while the lowest viscosity, setback viscosity, consistence viscosity increased remarkably. Germination also influenced the rheological properties of GPRG. The storage modulus(G′)during heating is lowest among the four kinds of starch because of the lowest amylose content.To study the Molecule characteristics of starch from germinated polished-rice-with-germ (GPRG).Methods: using SEM, HPLC, X– Ray Diffractometer and FT–IR to study the changes of the particle morphology,Molecular weigh,crystalli–nity and characteristic structure. Results: the granule morphology of starches underwent little change,the molecular weight,crystallinity has decreased,the ratio of absorbances 1047/1022 cm^-1 has decreased. Conclusions: Through the germination, GPRG amylase and GPRG amylopectin were degradated , the Molecule characteristics of starch from germinated polished - rice-with-germ (GPRG) has a obvious change.