葡萄酒、啤酒中二氧化硫、总二氧化硫检测方案(毛细管电泳仪)

智能文字提取功能测试中

HIGH PERFORMANCECAPILLARYELECTROPHORESIS SYSTEM DETERMINATION OF TOTAL SULFUR DIOXIDE IN WINE AND BEERLUMEX Method M 04-78-2012 INTRODUCTION Method allows determination of mass concentration of total sulfur dioxide (sulfurous acid and its salts， foodadditives E220-E228) in wine， wine materials， beer and beer products by capillary electrophoresis (CE)using capillary electrophoresis system“CAPEL-105M”. The mass concentration of total sulfur dioxide is regulated by normative documents to be held within 100-400 mg/L for different types of wine and wine materials and within 20-50 mg/L for beer products.According to European and Russian regulations it is allowed not to indicate on the labels the presence ofsulfur dioxide in beverages if its concentration is less than 10 mg/L. MEASUREMENT METHOD The CE method for the determination of mass concentration of total sulfur dioxide is based on a basichydrolysis of the sample with its subsequent separation in a fused silica capillary under the influence ofapplied electric field. Identification and quantification of the analyzed sulfur dioxide is performed by indirectdetection measuring UV absorption at 374 nm. MEASUREMENT RANGE Measurement range for total sulfur dioxide is 5.0-1000 mg/L. The presence of other inorganic anions (chloride， sulfate， nitrate， fluoride， phosphate， and carbonate) aswell as organic acids (acetic， tartaric， malic， citric， etc.) in a quantity typical for these types of productsdoes not deteriorate analysis. ADVANTAGES OF CE METHOD CE method for the determination of sulfur dioxide has a number of advantages compared with otheranalytical methods typically used for this purpose， such as photometry， titrimetry， etc. CE method is not hampered by： colored compounds； different reducing agents like ascorbic acid； different sulfur compounds. ● Additional steps (masking， lightening， etc.) are not required. ● Sample pretreatment time is only 15 minutes. Analysis time on“CAPEL-105M”CE system is less than 3 minutes. EQUIPMENT AND REAGENTS “CAPEL-105M"capillary electrophoresis system with high-voltage negative polarity is used in allmeasurements. Instrument control， data acquisition and data processing are performed using a personalcomputer running under“WINDOWS@XP/7/8" operating system with installed dedicated software package“ELFORUN@". All reagents must be of analytical grade or better. EXAMPLES OF REAL ANALYSES Buffer： chromate， with DEA and CTA-OH Capillary： Leff/ Ltot =50/60 cm， ID= 75 pm Sample injection： 300 mbar*s Voltage： -25kVTemperature：+20cDetection： 374 nm Sample： pretreated dry white wine Found，mg/L：1 -total sulfur dioxide (93) Sample： pretreated dark beer Found，mg/L：1- total sulfur dioxide (7.0) min The contents on this paper are subject to change without notice. Please， contact manufacturer LUMEX toget more detailed information. WWW.LUMEX.BIZ LUMEX INSTRUMENTS Office： pr. Obukhovskoi Oborony， Bldg.， St. Petersburg， RussiaPostal address： P..O..Box St.-Petersburg， RussiaTel.+ ( E-mail：lumex@lumex.ru； www.lumex.bizWWW.LUMEX.BIZ 绝大部分葡萄酒在配料表中都会标出含有二氧化硫，如果没有标出的也不代表没有含二氧化硫。SO2对葡萄酒的影响可谓是从内到外，主要有两种。第一，SO2通常作为保护剂添加到葡萄酒中，有杀死葡萄皮表面的杂菌(SO2几乎是酿酒师所能使用的唯一的细菌抑制剂)。第二。它又是一种抗氧化剂，在保护酒液的天然水果特性的同时防止酒液老化。尽管SO2对葡萄酒的酿制有很大作用，但是不可忽略的一点是，SO2含量过高时会使葡萄酒产生如腐蛋般的难闻气味，人体饮用后会引起急性中毒，严重的还可能引起肺水肿、室息、昏迷。因此，葡萄酒中的二氧化硫含量一直属于葡萄酒检测中要产格监控的检测项目。每个国家对酿酒过程中能加入的SO2最大限度都有专门的法律规定。欧盟规定红葡萄酒中SO2的最高含量为160mg/l，白葡萄酒和粉红葡萄酒为210mg/l，另外允许成员国在比较差的年份加入不超过40mg/l的SO2。由于SO2对人类身体有一定的毒牲作用，世界卫生组织规定每人依体重算，每天吸入SO2的最大量应控制在0.7mg/kg，也就是说，如果一个人体重是50kg，那么他吸入SO2的量不超过35mg为宜。另外，更加重要的是，在开瓶后你摇杯的时间里，葡萄酒中有30%-40%的SO2的会跟氧气结合而消失了。用毛细管电泳法可以测定葡萄酒、葡萄酒原料、啤酒和啤酒产品中总二氧化硫（亚硫酸盐）的质量浓度。毛细管电泳法测定总二氧化硫的原理是基于在施加电场的影响下，样品在熔融石英毛细管中分离并进行碱性水解。通过间接检测在374 nm处的紫外吸光度进行二氧化硫的分析和定量。