Lehrstuhl für Allgemeine Lebensmitteltechnologie , Technische Universität München , Maximus-von-Imhof-Forum 2 , D-85354 Freising , Germany.
Lehrstuhl für Biochemie , Technische Universität München , Lichtenbergstrasse 4 , D-85748 Garching , Germany.
J Agric Food Chem. 2019 Oct 30;67(43):12072-12083. doi: 10.1021/acs.jafc.9b05197. Epub 2019 Oct 16.
Phytostanyl fatty acid esters, which are being added to a variety of foods owing to their cholesterol-lowering properties, are susceptible to thermally induced oxidation reactions. Using sitostanyl oleate as an example, we, in this study, aimed at developing strategies for the detection and the quantitation of acyl chain oxidation products (ACOPs). The elaborated ultra high performance liquid chromatography-mass spectrometry MS/MS-based approach involves (i) derivatizations of hydroxy and oxo groups, (ii) combined use of atmospheric pressure chemical ionization and electrospray ionization as ionization techniques, and (iii) establishment of selective multireaction monitoring transitions. These strategies allow the identification of a broad spectrum of nonpolar short-chain as well as polar short- and long-chain hydroxy, epoxy, and oxo ACOPs. Semiquantitative assessments showed that sitostanyl 9,10-epoxystearate was the predominating ACOP resulting from thermo-oxidation of sitostanyl oleate at 180 °C for 30 min. The elaborated analytical approach paves the way to narrow the existing knowledge gap on the fate of phytostanyl fatty acid esters upon heat treatments.
植物甾烷脂肪酸酯因其降低胆固醇的特性而被添加到各种食品中，容易受到热诱导氧化反应的影响。本研究以甾醇油酸酯为例，旨在开发检测和定量酰基链氧化产物（ACOP）的策略。所阐述的基于超高效液相色谱-串联质谱 MS/MS 的方法包括：（i）羟基和氧基团的衍生化，（ii）大气压化学电离和电喷雾电离的联合使用作为电离技术，以及（iii）选择性多反应监测转换的建立。这些策略允许识别广泛的非极性短链以及极性短链和长链羟基、环氧化物和氧 ACOP。半定量评估表明，在 180°C 下热氧化 30 分钟后，植物甾烷 9,10-环氧硬脂酸酯是甾醇油酸酯热氧化产生的主要 ACOP。所阐述的分析方法为缩小植物甾烷脂肪酸酯在热处理过程中命运的现有知识差距铺平了道路。
