Rapid Identification of Adulteration in Edible Vegetable Oils Based on Low-Field Nuclear Magnetic Resonance Relaxation Fingerprints.

Zhi-Ming Huang,Da-Xiu Wei,Jiachen Wang,Jia-Xiang Xin,Jing Zhu,Yi Li,Ye-Feng Yao,Xue-Lu Wang,Shan-Shan Sun

doi:10.3390/foods10123068

Abstract

Most current approaches applied for the essential identification of adulteration in edible vegetable oils are of limited practical benefit because they require long analysis times, professional training, and costly instrumentation. The present work addresses this issue by developing a novel simple, accurate, and rapid identification approach based on the magnetic resonance relaxation fingerprints obtained from low-field nuclear magnetic resonance spectroscopy measurements of edible vegetable oils. The relaxation fingerprints obtained for six types of edible vegetable oil, including flaxseed oil, olive oil, soybean oil, corn oil, peanut oil, and sunflower oil, are demonstrated to have sufficiently unique characteristics to enable the identification of the individual types of oil in a sample. By using principal component analysis, three characteristic regions in the fingerprints were screened out to create a novel three-dimensional characteristic coordination system for oil discrimination and adulteration identification. Univariate analysis and partial least squares regression were used to successfully quantify the oil adulteration in adulterated binary oil samples, indicating the great potential of the present approach on both identification and quantification of edible oil adulteration.

Highlights

Edible vegetable oils are basic foodstuffs that are very commonly used worldwide.Many different types of commercial vegetable oils are currently available, which range from traditional and generally inexpensive canola oil, peanut oil, soy oil, and sunflower oil to more exotic and expensive flaxseed oil and olive oil
The relaxation fingerprints obtained for six types of edible vegetable oil, including flaxseed oil (FO), olive oil (OL), soybean oil (SO), corn oil (CO), peanut oil (PO), and sunflower oil (SFO), are demonstrated by principal component analysis (PCA) to have sufficiently unique characteristics to enable unambiguous identification
The present work proposed a simple, accurate, and rapid identification approach for identifying adulteration in edible vegetable oil samples based on their magnetic resonance relaxation fingerprints obtained from LF-nuclear magnetic resonance (NMR) spectroscopy measurements

Summary

Introduction

Edible vegetable oils are basic foodstuffs that are very commonly used worldwide.Many different types of commercial vegetable oils are currently available, which range from traditional and generally inexpensive canola oil, peanut oil, soy oil, and sunflower oil to more exotic and expensive flaxseed oil and olive oil. Most commercially available edible vegetable oils are produced by responsible vendors, economic motivations have led to the unreported adulteration of vegetable oils with less expensive vegetable oil substitutes by unscrupulous vendors [1,2] This is a serious issue because it represents consumer deception, and because it can lead to health and safety issues [3]. A number of conventional analytical techniques have been applied for identifying adulteration in edible vegetable oils, which include gas chromatography (GC) [4], highperformance liquid chromatography (HPLC) [5], and GC combined with mass spectrometry (GC-MS) [6] These techniques are destructive, and often require laborious and time-consuming sample pretreatment and preparation.

Objectives

Methods

Results

Conclusion