Barnett D, Davis E G
J Chromatogr Sci. 1983 May;21(5):205-8. doi: 10.1093/chromsci/21.5.505.
A gas chromatographic procedure was developed to measure SO2 in the presence of water vapour up to saturation level in the headspace atmospheres of packaged food. A Teflon column packed with Chromosorb 108 was used to separate CO2, SO2, and H2O in that order, then SO2 was determined using an electrolytic conductivity detector operated in a non-catalytic mode. A permeation-tube apparatus, producing SO2 and modified to permit humidification of the effluent stream, was used to calibrate the instrument, and a heated syringe technique was devised which overcame problems of sampling low levels of SO2 in the presence of water vapour. In food headspaces the method was used to determine SO2 at the ng ml-1 level with relative deviations of less than 5%.
开发了一种气相色谱法，用于在包装食品顶空气氛中存在高达饱和水平的水蒸气的情况下测量二氧化硫。使用填充有Chromosorb 108的聚四氟乙烯柱按此顺序分离二氧化碳、二氧化硫和水，然后使用以非催化模式运行的电解电导检测器测定二氧化硫。使用产生二氧化硫并经过改进以允许对流出物流进行加湿的渗透管装置对仪器进行校准，并设计了一种加热注射器技术，该技术克服了在水蒸气存在下对低水平二氧化硫进行采样的问题。在食品顶空中，该方法用于测定纳克/毫升水平的二氧化硫，相对偏差小于5%。
