CAJ | 학술논문

建立了盐酸水解，索氏提取总脂肪酸，氢氧化钾甲醇溶液甲酯化，硫酸氢钠处理，气相色谱测定奶粉中二十二碳六烯酸（ DHA）含量的方法。采用三因素三水平正交试验对氢氧化钾甲醇溶液甲酯化条件进行了优化，得到最优反应条件为：1 mol／L氢氧化钾在25℃反应5 min。甲酯化衍生液经硫酸氢钠处理，在SP-2560气相色谱柱（100 m ×0.25 mm×0.20μm）上进行55 min程序升温测定 DHA 含量。DHA 在5.0~300 mg／L 范围内呈良好线性，相关系数为0.9999。DHA质量浓度为10、50、100 mg／L时目标峰峰面积的相对标准偏差（ RSD）分别为3.4％、1.2％和1.1％。方法检出限为2 mg／kg，回收率为90.4％~93.5％。该法用于实际样品的检测，结果令人满意。
건립료염산수해，색씨제취총지방산，경양화갑갑순용액갑지화，류산경납처리，기상색보측정내분중이십이탄륙희산（ DHA）함량적방법。채용삼인소삼수평정교시험대경양화갑갑순용액갑지화조건진행료우화，득도최우반응조건위：1 mol／L경양화갑재25℃반응5 min。갑지화연생액경류산경납처리，재SP-2560기상색보주（100 m ×0.25 mm×0.20μm）상진행55 min정서승온측정 DHA 함량。DHA 재5.0~300 mg／L 범위내정량호선성，상관계수위0.9999。DHA질량농도위10、50、100 mg／L시목표봉봉면적적상대표준편차（ RSD）분별위3.4％、1.2％화1.1％。방법검출한위2 mg／kg，회수솔위90.4％~93.5％。해법용우실제양품적검측，결과령인만의。
A method to determine docosahexenoic acid( DHA)in milk powder by gas chroma-tography was established. The milk powder samples were hydrolyzed with hydrochloric acid, extracted to get total fatty acids by Soxhlet extractor,then esterified with potassium hydroxide methanol solution to form methyl esters,and treated with sodium hydrogen sulfate. The optimal experiment conditions were obtained from orthogonal experiment L9(33)which performed with three factors and three levels,and it requires the reaction performed with 1 mol/L potassium hydroxide solution at 25 ℃ for 5 min. The derivative treated with sodium hydrogen sulfate was separated on a column of SP-2560(100 m×0. 25mm×0. 20 μm),and determined in 55 min by temperature programming-gas chromatography. Good linearity was obtained in the range 5. 0-300 mg/L with the correlation coefficient of 0. 999 9. The relative standard deviations( RSDs) were 3. 4%,1. 2% and 1. 1% for the seven repeated experiments of 10,50 and 100 mg/L of DHA,respectively. The limit of detection was 2 mg/kg,and the recoveries of DHA were in the range of 90. 4%-93. 5%. The results are satisfactory through the tests of practical samples.