不同加工精度对大米中镉含量的影响

将46组稻谷用砻谷机砻谷后得到糙米,再用碾米机碾去糙米的糠层,根据碾米时间的不同,将稻谷分为糙米、四级精米、三级精米、二级精米、一级精米,三级糠粉和一级糠粉；用原子吸收分光光度计测定46组大米各组分的镉含量并进行分析,得出镉含量的大小顺序为：三级糠粉>一级糠粉>糙米>四级精米>三级精米>二级精米>一级精米；通过将大米中各组分两两比较进行配对样本T检验,得出一级糠粉与糙米具有统计意义(P＜0.05),其余比较分析具有较大差异性(P＜0.01)；不同加工精度的精米中重金属镉含量也存在显著差异：四级精米镉含量最高,为(0.40±0.24)mg/kg,一级精米镉含量最低,为(0.22±0.13)mg/kg；稻谷的糠层对镉的富集作用最强,对于整个稻米镉含量分析有较大影响。

Effect of different processing precisionon cadmium content in rice

46 groups of rice were husked with rice Huskers to obtain brown rice, and then rice mills were used to grind the furs of brown rice. According to set the time of rice milling, rice was divided into brown rice, 4-grade refined rice, 3-grade refined rice, and 2-grade refined rice, 1-class refined rice, level 3 bran powder and level 1 bran powder; Determination and analysis of cadmium content of 46 groups of rice by atomic absorption spectrophotometer showed that the order of cadmium content was: Level 3 bran powder> Level 1 bran powder> Brown rice> 4-grade refined rice > 3-grade refined rice >2-grade refined rice >1-class refined rice; By comparing the two groups of rice in two groups to carry out the pairing sample T test, it is concluded that the level 1 bran powder and brown rice have statistical significance(P 0.05), and the remaining comparative analysis has a large difference(P 0.01); There are also significant differences in the cadmium content of heavy metals in refined rice with different processing precision: the highest content of cadmium in refined rice in the fourth grade is(0.40 ± 0.24) mg/kg, and the lowest content of cadmium in refined rice is(0.22 ± 0.13) mg/kg; The bran powder layer of rice has the strongest effect on cadmium enrichment and has a great influence on the analysis of cadmium content in rice.