【摘要】 采用苦味酸对明胶的高效沉淀作用构建了两步沉淀检测乳明胶的方法。用苦味酸对系列浓度的明胶掺假乳进行了检测,获知该方法的检测敏感度高达20 mg/dL,满足日常检测要求。依据以上结论组装了便携式乳明胶检测试剂盒,其试剂稳定,结果可靠,可以推广应用。更多还原

【Abstract】 Although gelatin is a usual food additive,it is not allowed to be added into raw milk.In our experiment about the detection skill of milk-gelatin,it has been found that excess Hg(Ⅱ) or Ag(Ⅰ) could completely precipitate milk-protein,but could not precipitate gelatin at all.The guessed cause of this unusual phenomenon is that,there is no cysteine in gelatin amino components,thus there is no active thiol-group,a soft base,to react with Hg(Ⅱ) or Ag(Ⅰ),the soft acids,to generate the precipitation—double salt of metal-protein sulfide.Based on this cognition,a "two-step precipitation assay" to detect gelatin in milk was established applying the ability that carbazotic acid precipitates gelatin efficiently.The standard concentration of gelatin in adulterated milk was detected using the saturated carbazotic acid solution,results indicated that the method has a pretty high sensitivity of 20 mg/dL,which is sensitive enough to meet the needs of the routine demands.According to the results above,a portable reagent kit to detect gelatin in milk with high stability and reliability was established.更多还原