| In this paper, the composition, granule sizes, crystalloid, digestive characteristics of indica and glutinous starch from Anhui were studied by spectrophotometer, optical microscopy, X-diffraction ray. This investigation was to provide theory for starchy food further developed. The results were as fellows:1. The granule morphology of starches was analyzed by light microscopy. The result indicated that all granules of indica and glutinous starches were tiny, and contained triangle and polygon. After gelatinization, starch swollen, particle state disappeared, most of gelatinized starch was swollen and broken, and partial gelatinization starch was not completely broken, and kept cystic form.2. X-diffraction ray analysis indicated that both rice starch particle were belong to A-type crystal. The native crystallinities of indica and glutinous starch were26.27%and35.11%, respectively. After gelatinized completely, crystal structure almost disappear. For partial gelatinization starch, X-diffraction showed tha tinter-granules exsited crystal structure. The crystallinities of partial gelatinization indica rice and glutinous rice were11.14%and22.30%, respectively. After gelatinized and partial gelatinization, the changed of the crystalline properties after storage at25℃,4℃and-18℃were studied. The results indicated that, for the gelatinized indica starch, during the storage at the temperature of25℃、4℃and-18℃, their crystallinities raised from0%to7.98%,12.53%and11.77%respectively. The gelatinized glutinous starch, their crystallinities raised from0%to0.5%,6.60%and3.75%, respectively. For partial gelatinization indica starch after storage at25℃,4℃and-18℃, their crystallinities increased from11.4%to19.11%,24.45%and22.89%, respectively. For partial gelatinization glutinous starch, their crystallinities increased from11.4%to2.98%,30.75%and26.91%, respectively. Compared the partial gelatinization starch with the gelatinized starch, the results indicated that the crystal rate of partial gelatinized starch was much faster. Compared with the storage at-18℃、25℃and4℃, the crystal rate of partial gelatinized starch storage at4℃was much faster. Compared the indica rice with glutinous rice, the crystal rate of indica rice was much fast, this may be associated with amylose content.3. When the starch sample gelatinized and partially gelatinized, a large number amylose dissolved. Retrograded after1day, the amylose crystaled rapidly, leakage amount of amylose decreased quickly, and then the content of amylose kept steadily.4. The digestive properties of different gelatinization extent starch storage at 25℃,4℃and-18℃were determined. The results indicated that RDS decreased, SDS and RS increased with the storage time increased. After1day, the content of RS was no change. The RS content in the completely gelatinized indica rice starch was4.1%,8.6%,6.5%, respectively. Compared with RS content of gelatinized starch at, RS increased2.7%,7.2%,5.1%, respectively. For the content of completely gelatinized glutinous rice starch, RS was40.9%,1.5%,1.3%, respectively. Compared with storage at0day, RS increased0.0%,0.6%,0.4%, respectively. The RS content of partial gelatinization indica rice starch, RS was13.8%,17.8%,15.8%, respectively. Compared with storage at Oday, the content of RS increased5.7%,9.7%,7.1%, respectively. The RS content of partial gelatinization glutinous rice starch, RS was5.4%,6.5%,6.0%, respectively. Compared with storage at Oday, RS increased0.1%,1.2%,0.7%, respectively. Compared the partial gelatinization starch with the gelatinized starch, at the same storage temperature, the RS and SDS content of partial gelatinization starch were more than completely gelatinized starch. Compared with the storage at-18℃,25℃and4℃, the storage at4℃was easy to be RS. Compared the indica rice with glutinous rice, indica rice was easy to be RS. |
PDF Full Text Request