摘要
稻谷中脂肪酸经提取后,采用返滴定法,先用过量的氢氧化钾标准滴定溶液与其反应,再用硫酸标准滴定溶液滴定过量的碱液,然后计算脂肪酸值。结果表明,采用本方法与现行国家标准相比结果一致,但本方法终点易于判断,重复性较好(RSD=0.95%)。
A modified method of determination of fatty acid in paddy by using back titration was established. When the fatty acid in paddy was extracted,which was reacted with excessive standard KOH solution,then using standard1/2 H2 SO4 solution titrate the excessive alkali,finally calculate the fatty acid value in paddy. The results showed that the values of this method were basically consistent with the current national standard,and the end point of titration was judged easily,the reproducibility of the results( RSD = 0. 95%) was well. This method is simple,accurate and suitable for the determination of fatty acid value in paddy.
引文
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