School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea.
Sci Rep. 2021 Mar 15;11(1):5947. doi: 10.1038/s41598-021-85288-1.
Accurate and precise determination of free fatty acid (FFA) contents is essential for quality control and assurance in food production. Herein, a mass spectrometric study was performed to develop a sample preparation protocol that can minimize exogenous FFA contamination during the quantification of FFA in food. The quantities of exogenous FFAs were measured using various combinations of seven pretreatment methods for a sample tube, three extraction methods, and four types of sample tubes. Methanol washing could effectively reduce exogenous palmitic acid (PA) and stearic acid (SA) by 73 and 64%, respectively, in contrast to furnace baking resulting in a decrease in the amount of PA and SA contaminants by 50 and 37%, respectively. A lower amount of FFA contaminants was extracted from glass tubes during comparative analysis of the four different sample tubes studied. A combination of a methanol-washed glass tube and chloroform extraction solvent was determined to be the optimal method for minimizing the error in FFA quantification. The optimized sample preparation protocol used for FFA quantification can lower the amount of foreign palmitic acid and stearic acid to the sub-nanomolar level in the analysis of FFAs in skimmed milk.
准确、精确地测定游离脂肪酸 (FFA) 的含量对于食品生产的质量控制和保证至关重要。在此，进行了一项质谱研究，以开发一种样品制备方案，该方案可以在定量食品中的 FFA 时最大限度地减少外源性 FFA 污染。使用样品管的七种预处理方法、三种提取方法和四种类型的样品管的各种组合来测量外源性 FFAs 的量。与炉烘烤相比，甲醇洗涤分别可有效减少外源性棕榈酸 (PA) 和硬脂酸 (SA)73%和 64%，而炉烘烤可分别减少 PA 和 SA 污染物的含量 50%和 37%。在对研究的四种不同类型的样品管进行比较分析时，从玻璃管中提取的 FFA 污染物量较少。甲醇洗涤的玻璃管和氯仿提取溶剂的组合被确定为最小化 FFA 定量误差的最佳方法。用于 FFA 定量的优化样品制备方案可将脱脂乳中 FFA 分析中外源性棕榈酸和硬脂酸的量降低到亚纳摩尔水平。
