Lehrstuhl für Allgemeine Lebensmitteltechnologie, Technische Universität München, Freising-Weihenstephan, Germany.
J Agric Food Chem. 2011 May 25;59(10):5204-14. doi: 10.1021/jf104930z. Epub 2011 Apr 22.
Approaches for the capillary gas chromatographic (GC) based analysis of intact plant stanyl esters in enriched foods were developed. Reference compounds were synthesized by enzyme-catalyzed transesterifications. Their identities were confirmed by means of mass spectrometry. Using a medium polar trifluoropropylmethyl polysiloxane stationary phase, long-chain plant stanyl esters could be separated according to their stanol moieties and their fatty acid chains. Thermal degradation during GC analysis was compensated by determining response factors; calibrations were performed for ten individual plant stanyl esters. For the analysis of low-fat products (skimmed milk drinking yogurts), the GC separation was combined with a "fast extraction" under acidic conditions. For fat-based foods (margarines), online coupled LC-GC offered an elegant and efficient way to avoid time-consuming sample preparation steps. The robust and rapid methods allow conclusions on both, the stanol profiles and the fatty acid moieties, and thus provide a basis for the authentication of this type of functional food ingredients.
开发了用于浓缩食品中完整植物甾烷酯的毛细管气相色谱 (GC) 分析方法。参考化合物通过酶催化的酯交换合成。通过质谱法确认了它们的身份。使用中等极性的三氟丙基甲基聚硅氧烷固定相，可以根据其甾醇部分和脂肪酸链对长链植物甾烷酯进行分离。通过测定响应因子补偿 GC 分析过程中的热降解；对十种植物甾烷酯进行了校准。对于低脂产品（脱脂牛奶饮用酸奶）的分析，GC 分离与酸性条件下的“快速提取”相结合。对于基于脂肪的食品（人造黄油），在线耦合 LC-GC 提供了一种优雅且高效的方法，可以避免耗时的样品制备步骤。这种稳健且快速的方法可以得出关于甾醇谱和脂肪酸部分的结论，从而为这种类型的功能性食品成分的验证提供了依据。
