Rapid detection of authenticity and adulteration of walnut oil by FTIR and fluorescence spectroscopy: a comparative study

Bingning Li; Haixia Wang; Qiaojiao Zhao; Jie Ouyang; Yanwen Wu

doi:10.1016/j.foodchem.2015.02.079

Rapid detection of authenticity and adulteration of walnut oil by FTIR and fluorescence spectroscopy: a comparative study

Food Chem. 2015 Aug 15:181:25-30. doi: 10.1016/j.foodchem.2015.02.079. Epub 2015 Feb 20.

Authors

Bingning Li¹, Haixia Wang², Qiaojiao Zhao², Jie Ouyang³, Yanwen Wu⁴

Affiliations

¹ Department of Food Science and Engineering, Beijing Key Laboratory of Forest Food Process and Safety, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China; Beijing Center for Physical and Chemical Analysis, Beijing 100089, China.
² Department of Food Science and Engineering, Beijing Key Laboratory of Forest Food Process and Safety, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China.
³ Department of Food Science and Engineering, Beijing Key Laboratory of Forest Food Process and Safety, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China. Electronic address: ouyangjie@bjfu.edu.cn.
⁴ Beijing Center for Physical and Chemical Analysis, Beijing 100089, China. Electronic address: wu_yanwen@163.com.

PMID: 25794716
DOI: 10.1016/j.foodchem.2015.02.079

Abstract

Fourier transform infrared (FTIR) and fluorescence spectroscopy combined with soft independent modeling of class analogies (SIMCA) and partial least square (PLS) were used to detect the authenticity of walnut oil and adulteration amount of soybean oil in walnut oil. A SIMCA model of FTIR spectra could differentiate walnut oil and other oils into separate categories; the classification limit of soybean oil in walnut oil was 10%. Fluorescence spectroscopy could differentiate oil composition by the peak position and intensity of emission spectrum without multivariate analysis. The classification limit of soybean oil adulterated in walnut oil by fluorescence spectroscopy was below 5%. The deviation of the prediction model for fluorescence spectra was lower than that for FTIR spectra. Fluorescence spectroscopy was more applicable than FTIR in the adulteration detection of walnut oil, both from the determination limit and prediction deviation.

Keywords: Adulteration; Authenticity; Chemometrics; FTIR; Fluorescence spectroscopy; Walnut oil.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Dietary Fats, Unsaturated / analysis
Food Contamination / analysis
Juglans / chemistry*
Plant Oils / chemistry*
Spectrometry, Fluorescence / methods*
Spectroscopy, Fourier Transform Infrared / methods*

Substances

Dietary Fats, Unsaturated
Plant Oils