婴幼儿配方粉及成人营养品中脂肪酸含量检测方法的性能研究

Performance of Testing Methods of Fatty Acids in Infant Formula and Adult Nutritional Products

目的:建立适用于婴幼儿配方粉及成人营养品中脂肪酸检测的方法,并在不同基质中验证其性能。方法:在AOAC 2012.13方法基础上进一步修改建立了直接甲酯化法,并对其检测婴幼儿配方食品及成人营养品中主要功能性脂肪酸的能力进行验证。方法验证包括其准确性、回收率、精确度及定量限。本实验还研究了此方法在7种不同基质(乳基、豆基、部分水解蛋白及氨基酸配方)婴幼儿配方粉中的适用性,并与现行国标GB 5413.27-2010检测4种脂肪酸的能力进行了比对。同时,还评价了此方法检测包埋DHA原料的能力。结果:直接甲酯化法表现出了良好的准确性、回收率及精确度,在不同基质及使用不同包埋工艺的DHA原料中均显示了很好的适用性。此方法与现行国标方法测定7种乳粉试样中的4种脂肪酸的结果一致性均在90%~106%范围内,表现出了很高的一致性。结论:直接甲酯化法预处理步骤简单、方便、快捷,作为乳粉样品中脂肪酸含量的日常检测方法具有较大的推广潜力及价值。

Objective To set up a method to accurately and efficiently analyze the functional fatty acids in infant formula and nutritional products with different matrices.Method A direct transesterification method was established based on the AOAC official method 2012.13 to determine four main label claim fatty acids including linoleic acid,α-linolenic acid,arachidonic acid ARA,and docosahexenoic acid DHA in infant formula and pediatric/adult nutritional products.Different parameters of the method were validated,including accuracy,recovery,precision,and the limit of quantitation（LOQ）.The performance of the method was also assessed in 7 milk powder products with different matrices,and its testing results were compared to GB 5413.27-2010 results.The capability of the method to measure encapsulated DHA ingredients with different encapsulation process was also discussed.Result The established direct transesterification method showed good accuracy,recovery,and precision,and good suitability to different nutritional product matrices and encapsulated DHA ingredients.Also,the established method showed high results agreement to the current GB method when testing the four fatty acids in the 7selected powder products.Conclusion The established direct transesterification method included a very simple sample preparation procedure,and was fast and convenient to use,indicating a great potential for the routine test of fatty acids in infant formula and nutritional products.