甲醛-碘量法测定啤酒中的二氧化硫

Determination of sulfur dioxide in beer by formaldehyde iodometry

摘要: 探讨了用甲醛作掩蔽剂碘量法测定啤酒中残留的二氧化硫 .最佳分析条件 :p H为 3～ 4 ,甲醛用量为 SO2 含量的 2～ 4倍 ,掩蔽时间为 4 min,温度 2 5～ 3 3℃ .该法的检出限为 2× 1 0 - 5g/kg,可满足啤酒中二氧化硫的测定 .

Abstract: A method of determination of sulfur dioxide in beer with iodometry by using formaldehyde as masking reagent is reported.The optimal conditions are as follows:pH is 3~4,the amount of formaldehyde is 2 to 4 times over the amount of sulfur dioxide,masking time is 4 min.,and tempeature is 25~33 ℃.The detection limit is 2×10 -5 g/kg.This method can be used to determine the sulfur dioxide in beer satisfactorily.