Developing FT-NIR and PLS1 Methodology for Predicting Adulteration in Representative Varieties/Blends of Extra Virgin Olive Oils.
It was previously demonstrated that Fourier transform near infrared (FT-NIR) spectroscopy and partial least squares (PLS1) were successfully used to assess whether an olive oil was extra virgin, and if adulterated, with which type of vegetable oil and by how much using previously developed PLS1 calibration models. This last prediction required an initial set of four PLS1 calibration models that were based on gravimetrically prepared mixtures of a specific variety of extra virgin olive oil (EVOO) spiked with adulterants. The current study was undertaken after obtaining a range of EVOO varieties grown in different countries. It was found that all the different types of EVOO varieties investigated belonged to four distinct groups, and each required the development of additional sets of specific PLS1 calibration models to ensure that they can be used to predict low concentrations of vegetable oils high in linoleic, oleic, or palmitic acid, and/or refined olive oil. These four distinct sets of PLS1 calibration models were required to cover the range of EVOO varieties with a linoleic acid content from 1.3 to 15.5 % of total fatty acids. An FT-NIR library was established with 66 EVOO products obtained from California and Europe. The quality and/or purity of EVOO were assessed by determining the FT-NIR Index, a measure of the volatile content of EVOO. The use of these PLS1 calibration models made it possible to predict the authenticity of EVOO and the identity and quantity of potential adulterant oils in minutes.
NIR Technologies Inc., Oakville, ON, L6M 2M2, Canada. hazizian@nirtechnologies.com.
Hormoz
H
Azizian
Food and Drug Administration, Center for Food Safety and Applied Nutrition, Office of Regulatory Science, College Park, MD, USA. magdi.mossoba@fda.hhs.gov.
Magdi M
MM
Mossoba
Food and Drug Administration, Center for Food Safety and Applied Nutrition, Office of Regulatory Science, College Park, MD, USA.
Ali Reza
AR
Fardin-Kia
Food and Drug Administration, Center for Food Safety and Applied Nutrition, Office of Regulatory Science, College Park, MD, USA.
Sanjeewa R
SR
Karunathilaka
Guelph Food Research Center, Agriculture and Agri-Food Canada, Guelph, ON, Canada.
John K G
JK
Kramer
D005227:Fatty Acids / Q000032:analysis*; D005506:Food Contamination / Q000032:analysis*; D016018:Least-Squares Analysis; D000069463:Olive Oil / Q000032:analysis*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*; D055549:Volatile Organic Compounds / Q000032:analysis*
D005227:Fatty Acids; D000069463:Olive Oil; D055549:Volatile Organic Compounds
Extra virgin olive oil; FA markers; FT-NIR; PLS; Volatile compounds
Lipids. 2005 Aug;40(8):855-67
16296405
Lipids. 2015 Jul;50(7):705-18
26050093