15C-6 |
Detection of hazelnut oil adulteration with fourier transform infrared spectroscopy (FT-IR) |
B. F. OZEN, Food Science, Purdue University, 1160 Food Science Bldg, W. Lafayette, IN 47907, A. Tay, Food Science and Technology, The Ohio State University, 2015 Fyffe Road, Columbus, OH 43210, and L. J. Mauer, Food Science, 1160 Food Science Bldg, W. Lafayette, IN 47907. Methods for detecting adulteration of olive oil with hazelnut oil have received much attention due to the similar compositions of olive oil and hazelnut oil and the difficulty in differentiating between them. Adulteration of hazelnut oil, itself, with cheaper oils also has become a concern. FT-IR spectroscopy has been used successfully to detect adulteration of olive oils with different types vegetable and nut oils, and similar methods could be developed to detect hazelnut oil adulteration. The objectives of this study were to: 1) differentiate between hazelnut and other oils, 2) detect the adulteration of extra virgin olive oil with hazelnut oil, and 3) detect the adulteration of hazelnut oil with different types of oils using FT-IR spectroscopy and multivariate statistical procedures. Spectra of extra virgin olive oil, hazelnut oil, and seven types of oils were collected with a FT-IR equipped with a ZnSe-ATR cell and MCTA detector. Olive oil was adulterated with hazelnut oil (5-50%), hazelnut oil was adulterated with sunflower oil (2-10%), and IR spectra of adulterated oils were obtained. Discriminant analysis and PLS were used to analyze data. Classification of hazelnut oil, olive oil, and different types of vegetable oils was achieved successfully with FT-IR. The detection level for sunflower oil adulteration of hazelnut oil was 2%, and the correlation coefficient for the PLS model was 0.94. Adulteration of virgin olive oil with hazelnut oil could be detected only at 25% and higher. FT-IR is a powerful tool to detect the hazelnut oil adulteration by other oils, but not to detect low levels of hazelnut oil in olive oil. Adulteration as low as 2% could be detected accurately and rapidly using FT-IR in combination with multivariate statistics for hazelnut oil adulterated by sunflower oil.
Session 15C, Food Chemistry: Food composition and analysis
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