强化淀粉类食品中7 种水溶性维生素的快速测定

建立高效液相色谱-二极管阵列-荧光联用法同时检测营养强化淀粉类食品中7 种水溶性维生素含量的方法。样品经淀粉酶60 ℃酶解45 min，调pH值提取后，经十二烷基硫酸钠（5 mmol/L，加入0.1%磷酸，三乙胺调pH 3.0）-乙腈梯度洗脱，VB1、烟酸、烟酰胺在不同波长下进行检测，VB2、吡哆醛、吡哆醇、吡哆胺采用目标物出峰时间段转变激发、发射波长检测。7 种维生素在各自线性范围内线性关系良好，相关系数r2为0.999 6～0.999 9，加标回收率为90.5%～102.5%，检出限为0.01～0.08 mg/100 g，定量限为0.025～0.26 mg/100 g。方法快速、高效，适用于大批量强化淀粉类食品中7 种水溶性维生素的同时测定。

Rapid Determination of Seven Water-Soluble Vitamins in Starch-Fortified Foods

A method using high performance liquid chromatography with diode array detector and fluorescence detector (HPLC-DAD-FLD) was established to simultaneously analyze seven water-soluble vitamins in starch-fortified foods. The sample was hydrolyzed by amylase at 60 ℃ for 45 min and ultrasonically extracted after pH adjustment. Chromatographic separation was carried out by gradient elution using 5 mmol/L sodium dodecyl sulfate solution containing 0.1% phosphoric acid adjusted to pH 3.0 with triethylamine as mobile phase A and acetonitrile as mobile B. Vitamin B1, niacin and nicotinamide were detected at maximum UV absorption wavelengths. Good linearity was observed for all analytes with correlation coefficients (r2) of 0.999 6–0.999 9. The recoveries for spiked samples were 90.5%–102.5%, the limits of detection (LODs) were 0.01-0.08 mg/100 g, and the limits of quantitation were 0.025–0.26 mg/100 g. The developed method is rapid, efficient and suitable for the simultaneous determination of the seven vitamins in bulk starch-fortified foods.