橙汁中总糖和果肉的<i>δ</i><sup>13</sup>C测定及应用

橙汁中总糖和果肉的δ¹³C测定及应用

摘要: 稳定碳同位素分析是食品质量鉴别和产地溯源的有效手段。本工作结合分离技术，建立了元素分析-稳定同位素比值质谱（EA-IRMS）测定橙汁中总糖和果肉δ¹³C的方法，并研究了天然橙汁与模拟造假橙汁中总糖和果肉的碳同位素特征差异。实验结果表明，本方法不会导致同位素分馏，且标准偏差仅为0.1‰；初步研究证明，橙汁总糖与果肉的δ¹³C相近，而与甘蔗糖的δ¹³C差异明显，因此，以橙汁果肉作为内标物质鉴别橙汁中的C4植物糖是可行的。

Abstract: Stable carbon isotope analysis is an effective method for identifying the botanic origin of plant product. In this paper, δ¹³C of sugar and pulp of orange juice were determined by elementar analyzer-isotope ratio mass spectrometer(EA-IRMS)， combined with separation technology. The isotope difference between natural and laboratory imitated orange juice was presented. Results show that isotope fractionation is not observed， while sample preparation and the standard deviation are merely 0.1‰. The δ¹³C of pulp is identical to that sugar in the same juice and different with cane sugar significantly, which can be used in the detection of C4 sugar in orange juice.