小麦粉及其制品中乙酸本底对双乙酸钠 测定结果的影响

目的 探讨小麦粉及其制品中乙酸本底对双乙酸钠测定结果的影响。方法 依据GB 5009.277-2016, 分别对双乙酸钠、乙酸和乙酸钠标准溶液进行加酸和不加酸蒸馏, 经高效液相色谱上机分析比较结果; 使用无本底原料按添加食盐和白砂糖与否制作面包, 并对成品进行加酸与不加酸蒸馏, 经高效液相色谱仪上机分析比较结果。结果 双乙酸钠、乙酸和乙酸钠不加酸与加酸蒸馏测定结果的比值分别为49%、100%和10%; 添加和无添加食盐与白砂糖制作面包不加酸与加酸蒸馏测定结果比值分别为56%和100%。结论 GB 5009.277-2016中扣除乙酸本底的实验方法仅适用于不含双乙酸钠仅含游离乙酸的食品样品。

Effect of acetic acid background on the determination of sodium diacetate in wheat flour and its products

Objective To discuss the effect of acetic acid background on the determination of sodium diacetate in wheat flour and its products. Methods According to GB 5009.277-2016, the sodium diacetate, acetic acid and sodium acetate standard solutions were acidified and acid-free distilled respectively, and the results were compared by using high performance liquid chromatography. The breads were prepared by adding salt and white sugar or not using the material without sodium diacetate, the products were acidified and acid-free distilled, and the results were analyzed and compared by high performance liquid chromatography. Results The ratios of distillation with or without added acid of sodium diacetate, acetic acid and sodium acetate were 47%, 100% and 10%, respectively. The ratios of distillation with or without added acid of bread made with or without salt and sugar were 56% and 100%, respectively. Conclusion The experiment of deducting acetic acid background in GB 5009.277-2016 is only applicable to food samples without SDA and only free acetic acid.