高效液相色谱示差折光法测定食品中的塔格糖

Determination of tagatose in food by liquid chromatography refractive index detector

塔格糖是一种良好的低能量食品甜味剂,但过量食用可能导致肠胃不适。示差检测器是一种通用型检测器,适用于糖类物质的检测。采用高效液相色谱示差折光法测定食品中的塔格糖。试样用水提取,C18小柱净化,以乙腈-水(85+15,V/V)为流动相,通过氨基柱(4.6mm×250mm,5μm)分离后用示差折光检测器检测。塔格糖浓度在0.4mg/mL 8.0mg/mL之间呈良好线性,相关系数为0.9999。橙汁、酸酸乳、熏肉制品、饼干样品中在4.0、8.0、20.0g/kg添加水平的添加回收率在95.5%102.0%之间,相对标准偏差在2.03%3.70%(n=6),方法的测定低限为4g/kg。方法简便可靠,重现性好,适用于食品基质中塔格糖的测定。

Tagatose is a good sweet agent with low calorie,but it can cause intestinal distress if absorb too much.The refractive index detector is a kind of universal detector,applies to carbohydrate detected.A high performance liquid chromatography refractive index（HPLC-RID） method was developed to determination of tagatose in food.Sample was extracted with water,cleaned with SPE C18,separated on a NH2（4.6mm ×250mm,5μm） column with a mobile phase consisting of acetonitrile-water（85 ＋ 15,V / V）,detected by refractive index detector.The calibration curves of tagatose exhibited good linearity over a concentration range from 0.4mg / mL 8.0mg / mL,with correlation coefficients 0.9999.The average recoveries ranged of tagetose in orange juice,yogurt,bacon and cracker from 95.5 to 102.0% at spike levels of 4,8,20.0g / kg,and the relative standard deviations were between 2.03 3.70%（n = 6）.The limit of quantification was 4g / kg.This method is convenient,reproducible and suitable for the determination of tagatose in matrix food.