Oil: A Source of Light and Cause for Celebration
The use of light during holidays or festivals – in any form, including candles, lanterns, or fireworks – is significant, as we celebrate and look ahead to the future. Many friends and colleagues recently celebrated Diwali (where light represents the triumph of good over evil and light over darkness), and others begin Hanukkah, the Festival of Lights. When we consider the exceptional year of 2020 in particular, it becomes even more important to look ahead to brighter and hopeful days to come.
Hanukkah commemorates the miracle of oil, when a single cruse of oil that should have lasted no more than a single night instead burned for eight full days. In current day celebrations, the hanukkiah or Hanukkah Menorah (which contains eight candles, with an extra placed in the middle to light all others) plays a central role. However, the significance of oil is not forgotten. While olive oil may still be used to light these candles, foods fried in oil are consumed with pleasure during Hanukkah to commemorate the miraculous oil.
What better way to celebrate than with glorious food – fried delights of jelly filled doughnuts (sufganiyot), fried potato cakes (latkes), savory filled dough (knish), and many other types of fritters. The sufganiyah (singular) is thought to date back to the 15th century, though it has evolved through many forms and iterations. It was not until the 1920s that it gained true popularity, when sufganiyot (plural) were declared an official food of Hanukkah. With many variants commercially available, the taste is not only influenced by the choice of filling, but also the oil used in which to fry them. Some sufganiyah-connoisseurs even recommend a citrus filling to best complement those fried in olive oil.
Understanding oils’ properties: From quality to authenticity
Edible oils are comprised of more than 95% triacylglycerides (TAGs), which are molecules of glycerol containing three fatty acids, linked via ester bonds. It’s these fatty acids that influence the physical, chemical (/ organoleptic) and nutritional properties of oils and makes many oils significantly different from each other. For this reason, the triacylglyceride profiles are commonly studied to determine the product’s quality, classification, and authenticity.
Due to the diverse species of TAGs present across various edible oils, chromatographic techniques are commonly employed. However, the detailed characterization of profiles can still prove challenging. While analytical run times and data handling can be time consuming, some techniques may cause oxidation of the samples, thus impacting the composition and accuracy of results. Recent studies have explored the application of supercritical fluid chromatography, such as Ultra Performance Convergence Chromatography (UPC2) coupled with mass spectrometry for improved separation and reliable characterization of edible oil TAG profiles.
To discover more on analytical techniques for triacylglycerols characterization, read this application brief by Jinchuan Yang and Giorgis Isaac: Characterization of Triacylglycerols in Edible Oils Using the ACQUITY UPC2 System and Mass Spectrometry.