Mono-, Di-, and Triglycerides

Triglycerides (also called triacylglycerol, triacylglyceride, or TAG) are the main constituent of vegetable oil and animal fat, and make up most of the fats digested by humans. They are important in that they allow the uptake and transport of fat-soluble vitamins. Plus, they play a role in metabolism (unused saturated or monounsaturated fatty acids are stored by the body as triglycerides). However, triglyceride intake should be monitored because high levels of triglycerides have been linked to an increased risk of heart disease and stroke. Mono-, di- and tri-glycerides are related to fatty acids:
  • A monoglyceride is the condensation of one fatty acid and glycerol.
  • A diglyceride is the condensation of two fatty acids and glycerol.
  • A triglyceride is the condensation of three fatty acids and glycerol.

Efficient capillary GC columns with the ability to provide ample resolution are required for proper identification. Triglycerides are large compounds requiring a relatively high final oven temperature for elution in a reasonable time. Cool-on-column (COC) injection should be used. Use of a heated injection port can lead to sample discrimination and is not suggested. The syringe needle used must have a diameter small enough to fit inside the 0.53 mm I.D. guard column. Automated injection is highly recommended for consistency.

HPLC using a C18 phase is an alternative technique for the analysis of glycerides.
  • For faster analysis on any HPLC system, turn to Ascentis Express. These columns, based on Fused-Core technology, offer the performance of sub-2 μm particles but exhibit the backpressure of 3 μm particles.
  • The Ascentis Express C18 phase is also available in a more traditional 5 μm particle. The Fused-Core technology results in increased efficiency, whereas the 5 μm particles exhibit limited backpressure, allowing longer column lengths than that possible with the standard 2.7 μm Ascentis Express particles.

Technical Article:
Determination of Triglycerides and Waxes in Food Products Using Cool On-Column Injection and the MET-Biodiesel Capillary Column