Investigating the Thermal Stability of Omega Fatty Acid-Enriched Vegetable Oils

Foods. 2024 Sep 19;13(18):2961. doi: 10.3390/foods13182961.

Abstract

This study investigates the thermal stability of omega fatty acid-enriched vegetable oils, focusing on their behavior under high-temperature conditions commonly encountered during frying. This research aims to evaluate changes in fatty acid composition, particularly the degradation of essential omega-3, -6, and -9 fatty acids, and the formation of harmful compounds such as trans fatty acids (TFAs). Various commercially available vegetable oils labeled as containing omega-3, omega-6, and omega-9, including refined sunflower, high-oleic sunflower, rapeseed, and blends, were analyzed under temperatures from 180 °C to 230 °C for varying durations. The fatty acid profiles were determined using gas chromatography-mass spectrometry (GC-MS). The results indicated a significant degradation of polyunsaturated fatty acids (PUFAs) and an increase in saturated fatty acids (SFAs) and TFAs with prolonged heating. The findings highlight the varying degrees of thermal stability among different oils, with high-oleic sunflower and blended oils exhibiting greater resistance to thermal degradation compared to conventional sunflower oils. This study underscores the importance of selecting oils with favorable fatty acid compositions for high-temperature cooking to minimize adverse health effects associated with degraded oil consumption. Furthermore, it provides insights into optimizing oil blends to enhance thermal stability and maintain nutritional quality, crucial for consumer health and food industry practices.

Keywords: GC-MS; fatty acid profile; omega-3 fatty acids; omega-6 fatty acids; thermal degradation; trans fatty acids; vegetable oils.

Grants and funding

This research was funded by Iuliu Hațieganu University of Medicine and Pharmacy’s internal grant PCD no. 1300/45/13 January 13 2017. This paper was published under the frame of the European Social Fund, Human Capital Operational Programme 2014–2020, project no. POCU/380/6/13/125171.