利用凯氏定氮仪快速测定葡萄酒中二氧化硫

Quick determination of sulfur dioxide in wine by Kjeldahl apparatus

中文关键词:  凯氏定氮仪  葡萄酒  二氧化硫

英文关键词:Kjeldahl apparatus  wine  sulfur dioxide

中文摘要:

      目的 建立使用凯氏定氮仪快速检测葡萄酒中二氧化硫的方法。方法 利用凯氏定氮仪和全玻璃蒸馏法工作原理的相似之处, 将凯氏定氮仪用于葡萄酒中二氧化硫的测定。对比了凯氏定氮仪蒸馏和全玻璃蒸馏法的空白实验,确定了使用凯氏定氮仪快速检测葡萄酒中二氧化硫合适的样品量、滴定碘溶液浓度、蒸馏时间, 并进行了精密度实验、回收率实验。最后, 以8种市售葡萄酒为实验材料对比了凯氏定氮仪法与全玻璃蒸馏法对二氧化硫含量的检测结果。结果 凯氏定氮仪蒸馏和全玻璃蒸馏法的空白实验结果基本无差异。使用凯氏定氮仪进行葡萄酒中二氧化硫检测, 其合适样品量为40 mL, 滴定碘溶液浓度为0.1 mol/L或0.05 mol/L, 蒸馏时间大大缩短, 为8 min, RSD为1.36%, 平均回收率为(102.40±3.26)%, 且对8种市售葡萄酒样品的检测结果与全玻璃蒸馏法相比无显著性差异(P＞0.05)。结论 凯氏定氮仪法测定葡萄酒中的二氧化硫, 检测效率高, 精密度好, 准确度高, 可作为葡萄酒中二氧化硫的批量检测方法。

英文摘要:

      Objective To establish a method for quick determination of sulfur dioxide in wine using Kjeldahl apparatus. Method Kjeldahl apparatus was applied to the quick determination of sulfur dioxide in wine due to its similar operating principle with glass distiller. Blank test results were compared between the 2 methods. Optimized sample volume, iodine solution concentration and distilling time of the Kjeldahl apparatus method were determined. The precision experiment and recovery experiment were conducted. Sulfur dioxide in 8 kinds of wines was detected by Kjeldahl apparatus and glass distiller respectively. Results No significant differences were found between Kjeldahl apparatus result of blank test and that of glass distiller; The optimized conditions of sulfur dioxide determination in wine by Kjeldahl apparatus were as follows: sample amount was 40 mL, iodine solution concentration was 0.1 mol/L or 0.05 mol/L and distilling time was 8 min. RSD was 1.36% and the average recovery was (102.40±3.26) %. No significant difference was found between the results of Kjeldahl apparatus and glass distiller on the detection of 8 market samples (P＞0.05). Conclusion The Kjeldahl apparatus method had a high efficiency, a good precision and accuracy on the determination of sulfur dioxide in wines. It can be applied as a batch testing method for sulfur dioxide determination in wine.