食品中铝的铬天氰分光光度法前处理条件研究

摘要

探讨面制和膨松食品在不同消解方法及消解条件下对铝检测的影响。取1.0 g试样分别用湿法消解及干灰化法处理，另在干灰化法下取不同质量试样，分别在不同灰化时间，，灰化温度为600℃下进行灰化处理，铝的测定按（GB/T5009.182-2003）中分光光度法进行。湿法消解面制食品中铝的回收率为47.8%~56.0%，蓬松食品为52.2%~55.8%，干灰化法中面制食品中铝的回收率为71.0%~74.7%，蓬松食品为73.9%~75.6%，面制食品与蓬松食品在不同消化条件下的所得的加标测定结果均值间经t检验比较差异具有统计学意义（P＜0.05）；不同灰化时间面制食品铝的回收率为63.4%~90.2%，膨松食品为73.8%~92.0%，灰化时间在5、6、7、8、9 h时间内加标测定结果间经t检验比较差异有统计学意义（P＜0.05），不同灰化称样量中面制食品铝的回收率为68.8%~91.8%，称样量为4.0、3.0、2.0、1.0 g时所得加标测定结果经t检验比较差异有统计学意义（P＜0.05），膨松食品铝的回收率为79.8%~92.4%，称样量为4.0、3.0、2.0 g时所得加标测定结果经t检验比较差异有统计学意义（P＜0.05），在称样量2.0、1.0、0.5 g时所得加标测定结果经t检验比较没有统计学意义（P＞0.05）。干灰化法较湿法有更好的结果回收率，但是干灰化法中取样量和灰化时间的不同均会导致测定结果的回收率下降和重复性不足，主要和试样的无机化程度不足有关。%To discuss the influence of different digestion system in determining of aluminum with flour food and bulk food. To take 1.0 g sample digest with wet digestion method and dry ashing method to test aluminum by Chromazurine Spectrophotometry. Then take sample get dry ashing at 600℃in different digestion time and test aluminum by Chromazurine Spectrophotometry in GB/T5009.182-2003. Recovery rate of flour food that digest with wet digestion method was 47.8%-55.0%;bulk food was 52.2%-55.8%. Recovery rate of flour food that digest with dry ashing method by different sampling amount was 71.0%-74.7%;bulk food was 73.9%-75.6%. The results of flour food and bulk food of different digest method had statistically significant by t test (P<0.05). Recovery rate of flour food that digest with dry ashing method by different digestion time was 63.4%-90.2%;bulk food was 73.8%-92.0%. The results of digestion time at 5, 6, 7, 8, 9 h had statistically significant by t test (P<0.05). Recovery rate of flour food that digest with dry ashing method by different sample weight was 68.8 %-91.8 %, the results had statistically significant by t test (P<0.05) when sample weight was 4.0,3.0,2.0,1.0 g;bulk food was 79.8%-92.4%the results had statistically significant by t test(P<0.05) when sample weight was 4.0,3.0,2.0 g. Dry ashing method had higher recovery rate than wet digestion method in this test. But dry ashing method had different precision with different sampling amount and digestion time. That was caused by different digestion degree.