Yonsei Medical Center Measures Omega-3 Fatty Acid Content in Edible Oils Using Electromagnetic Waves

No Need for Pretreatment or Opening the Bottle

A method has been discovered to determine the amount of omega-3 fatty acids in edible oils without opening the container.

Yonsei Medical Center

On August 19, professors Oh Seungjae, Yang Nanhee, and Maeng Inhee from the Medical Convergence Research Institute at Yonsei Medical Center, in collaboration with Pohang Accelerator Laboratory and the Advanced Photonics Research Institute, announced that they have identified a simple way to measure the omega-3 fatty acid content in edible oils using terahertz waves. The results of this study were published in the international journal 'npj Science of Food.'

Omega-3 fatty acids offer a variety of health benefits, including reducing triglycerides, improving vascular function, preventing Alzheimer's disease, and inhibiting cancer cells. Alpha-linolenic acid, a plant-based omega-3 fatty acid, is an essential fatty acid that cannot be synthesized by the human body and must be obtained through food.

Perilla oil, which is composed of about 60% alpha-linolenic acid among its total fatty acids, is gaining attention as a health food. However, there are products on the market labeled as "perilla-flavored oil" that contain less than 20% perilla oil, making it important to check the actual omega-3 content. Traditional methods for analyzing omega-3 content, such as nuclear magnetic resonance and gas chromatography, have limitations due to high costs and lengthy analysis times.

Terahertz time-domain spectroscopy (THz-TDS) is a technology that can overcome these limitations. Terahertz waves (THz) are electromagnetic waves with wavelengths ranging from 0.03 to 3 mm. Unlike X-rays, they are harmless to the human body and possess excellent material penetration capabilities. This is a non-destructive measurement technology that can analyze samples without causing damage, and it is also highly sensitive to structural changes in molecules. Due to these characteristics, it is considered a next-generation medical diagnostic technology.

The research team applied both conventional component analysis methods and terahertz time-domain spectroscopy to various edible oils, including soybean oil, corn oil, and perilla oil, to verify the reliability and effectiveness of terahertz time-domain spectroscopy as a tool for determining alpha-linolenic acid content.

To determine the alpha-linolenic acid content in soybean oil, corn oil, and perilla oil, the team conducted nuclear magnetic resonance analysis, a traditional quantitative method. The alpha-linolenic acid content was found to be 58.5% in soybean oil, 3.6% in corn oil, and 8.0% in perilla oil, respectively. Fourier-transform infrared spectroscopy was also used to identify the molecular bond structures of the edible oils and determine their alpha-linolenic acid content.

The researchers then applied terahertz time-domain spectroscopy to the same oils and confirmed that the results matched those obtained with conventional methods. In the terahertz time-domain spectroscopy analysis, oils with higher alpha-linolenic acid content showed proportionally higher refractive indices and absorption coefficients. The refractive index indicates how much the speed of light slows down within a substance, while the absorption coefficient shows how much light is absorbed and weakened as it passes through the material. This means that by examining the refractive index and absorption coefficient values obtained through terahertz time-domain spectroscopy, it is possible to quantitatively determine the alpha-linolenic acid content in oils.

Furthermore, the research team succeeded in distinguishing differences in the reflectance of terahertz waves based on alpha-linolenic acid content without opening the oil container. They measured the reflectance, which is the signal reflected back from the oil after being irradiated with terahertz waves. Since oils exhibit different reflectance values depending on their content, it was possible to distinguish the concentration of alpha-linolenic acid without extracting the oil.

Professor Oh Seungjae stated, "This study is a case of analyzing omega-3 content using terahertz technology. Our research demonstrates the possibility of simple, non-contact, non-destructive, and real-time verification of omega-3 content analysis without sample pretreatment, even while the oil remains in the bottle. This presents a new application field for terahertz technology."

This content was produced with the assistance of AI translation services.