Being able to analyze fats is essential for food manufacturers and producers as they play such an important role in both nutrition and food chemistry. When characterizing fat content in food, GC analysis of fatty acids as their methyl esters derivatives (FAMEs) is a useful tool. However, often fatty acids can be complicated to separate due to their complex mixture of saturated and polyunsaturated compounds, including cis and trans isomers.
We’ve looked at FAMEs analysis previously on Chromnews, but this article is going to take a deeper look at how rapid separation of saturated and unsaturated FAMEs can be completed without compromising resolution in high-throughput environments.
Separating fatty acids
Many regulatory methods for food testing, such as edible oils, infant milk formula and animal fat, require separation of saturated, polyunsaturated, and specific cis and trans fatty acid isomers. To complete this process a capillary column coated with a cyanopropyl stationary phase is required. In addition, this cyanopropyl phase needs to meet specific resolution requirements for some important FAME isomers, such as C18:1, C18:2 and C18:3 groups. These requirements are achieved when using long (about 100 m) GC columns. Unfortunately, such columns typically require long analysis times of more than 60 minutes to meet those requirements. For this reason, a typical FAME analysis leads to high cost of analysis and low productivity.
Introducing the new Agilent J&W DB-FastFAME GC columns
As previously shown, separating the fatty acid composition of food samples can be a complex and time-consuming process, requiring columns up to 200 m long to fully resolve the FAME compounds, which leads to low productivity. The latest Agilent J&W DB-FastFAME GC columns are designed with high resolution and high efficiency in mind. The columns are cyanopropyl-phase engineered for the fast and selective separation of saturated, polyunsaturated, and relevant cis and trans FAME isomers, including the FAMEs of oleic and elaidic acids, and linoleic and linoelaidic acids. The DB-FastFAME GC columns make it possible to separate these traditional FAMEs in under eight minutes. For the high-detail analysis of cis and trans positional isomers, as those commonly found in partially hydrogenated vegetable oils, the use of longer and more traditional FAME columns (for example, HP-88, and CP-Sil 88 for FAME) is still recommended. The J&W DB-FastFAME column is most suitable for separating:
- Dairy products (such as milk, butter, and cheese)
- Fish oil
- Animal fat
- Omega 3 & 6
- Vegetable oils (such as canola, soybean, olive, palm, and corn).
The following chromatogram demonstrates the use of a 20 m × 0.18 mm id, 0.20 µm DB-FastFAME column to analyze a 37-component FAME standard mixture. The compounds were all well resolved in under eight minutes, including AOCS and AOAC critical pairs. This result shows that rapid analysis is possible using high-efficiency columns, without compromising resolution.
The column is a critical part of the GC system, so ensuring you have the best option for your application is essential, especially with complex FAME compounds. The new Agilent J&W DB-FastFAME GC columns efficiently separate challenging fatty acids and FAMEs while reducing analysis time. Find out more: www.agilent.com/chem/db-fastfame. Alternatively, you can find out more about the whole Agilent FAMEs column range at the following link: https://www.agilent.com/en/promotions/fame-columns