Determination of Sulfur Dioxide in Food by Automatic Discontinuous Chemical Analyzer
This paper investigated a method for the determination of sulfur dioxide content in food by formaldehyde absorption,color development of para-rosaniline hydrochloride and automatic discontinuous chemical analyzer.After the samples were soaked in formaldehyde buffer absorption solution,the released sulfur dioxide was absorbed by formaldehyde solution to form stable methylol sulfonate addition compound,and then sodium hydroxide was added to decompose the addition compound,and para-rosaniline hydrochloride acted with the released sulfur dioxide to form a blue-purple complex.The sulfur dioxide in food was determined by automatic discontinuous chemical analyzer at 550 nm.The detection limit,quantitative limit,linearity,accuracy and repeatability of this method were analyzed.The results showed that the detection limit of the method was 2 mg/kg,and the limit of quantitation was 5 mg/kg.The absorbance of the method showed a good linear relationship with sulfur dioxide content in the range of 0.0-20.0 mg/L(r=0.999),and the relative standard deviation was less than 5％(n=6).There was no significant difference compared with the national standard method.The measured value of the certified reference material is within the range of the standard reference value.The established analytical method is highly automated,accurate,sensitive and precise,simple and rapid,and can avoid mercury toxicity and pollution,and can meet the determination of sulfur dioxide content in large quantities of food.
万方数据
维普
