食品灰分两种测定方法适用性的研究

The applicability of two methods for ash determination in food

目的探讨《食品安全国家标准食品中灰分的测定》(GB 5009.4-2010)中灰分的两种测定方法的区别,以及如何针对不同的样品选择适宜的测定方法。方法按国家标准规定的两种方法对不同样品的灰分进行测定,同时测定其含磷量,通过两者的关系推断适用的方法。结果检测了10种样本的灰分和磷含量,含磷较低的样品灰分测定可采用直接灰化法,测定结果的相对相差小于5%。含磷量高于0.4%的样品的灰分测定应采用加入灰化助剂的方法测定,且样品的取样量应尽可能小。结论食品中灰分的测定,虽然操作简单,但需注意细节问题,保证数据结果的准确性。

Objectives This paper discussed the difference between two ash determination methods de-scribed in GB 5009.4-2010 “National food safety standard determination of ash in foods” and how to choose appropriate method for different samples. Methods The ash in samples was determined by methods described in the national standard. In the first method, ashing auxiliaries magnesium acetate was used, while it was absent in the second method. The two methods were then compared, including sample selection, crucible process, sample carbonization, ashing and weighing. Results According to ash and phosphorus content in 10 samples containing less ash can be determined by direct ashing method, the relative phase difference measurement re-sults should be less than 5%. The method involving ashing auxiliaries was applicable to the special samples with phosphorus content above 0.4%. The sampling quantity is small enough. Conclusion It is simple to de-termine ash in foods, but attention should be paid to the details, in order not to affect accuracy of the result.