自动电位滴定法测定辣椒制品中二氧化硫残留量检测条件优化

Optimization of Determination Conditions of Sulfur Dioxide Residue in Chilli Products by Automatic Potentiometric Titration

摘要: 本文利用自动蒸馏仪对辣椒制品进行蒸馏处理，并用自动电位滴定仪进行二氧化硫残留量测定。通过正交试验L₁₆（4⁵），对检测条件进行了优化，得出最佳检测条件为蒸馏时间5 min，蒸馏水体积200 mL，接收液体积40 mL，搅拌速率8 r/min，电位变化率50 mV/min。在此条件下，辣椒制品中二氧化硫残留量的检测结果相对标准偏差在0.69%~0.95%之间，加标回收率在98.3%~99.6%之间。该方法稳定高效，检测速度快，操作简便，适合批量样品自动化检测的需要，可以为电位滴定应用于辣椒制品乃至各类食品中二氧化硫的测定提供参考。

Abstract: A method using automatic distillation apparatus coupled with automatic potentiometric titration was established to determine SO₂ residue in chili products. The optimal conditions were determined by orthogonal test L₁₆(4⁵),and the results were as follows:The distillation time 5 min,the volume of distilled water 200 mL,the volume of received solution 40 mL,the stirring speed 8 r/min,the potential change rate 50 mV/min. On this condition,the relative standard deviations were between 0.69%~0.95%,the standard addition recoveries were between 98.3%~99.6%. This method is simple,rapid and accurate. It’s suitable for the automated testing of large quantities of sample. The results can provide reference for study SO₂ residue in chili products and other food.