Development of food adulteration detection methods utilizing NMR spectroscopy

Abstract

Food adulteration is the act of diluting foodstuffs with undeclared fillers or outright substitution with other materials. While this practice has occurred since the dawn of recorded history it has remained difficult to combat. The reason for this struggle is simple; as new methods of detecting adulteration are developed, new adulteration methods are invented with the aim of circumventing detection. This invariably leads to a constant game of cat and mouse between those who commit fraud and anyone wishing to detect it. The motivation behind adulterating food is nearly always one of simple greed. So long as the fillers used as adulterants or substitute products are less expensive than the genuine product, the potential for greater profit is obvious. This research sought to address several of these practices by developing new or improved methods of detection with emphasis on speed, simplicity, and the use NMR spectrometers. Here we detect the presence of inexpensive robusta coffee (coffea canephora var. robusta) in coffees declared as being composed entirely of arabica coffee (coffea arabica). The addition of seed oil to dilute olive oils using a 400 MHz NMR instrument, particularly oils from high-oleic acid cultivars of safflower and sunflower is investigated. This research effort culminated with the discovery of the dilution of bovine hard cheeses with plant based oils and development of a method to detect it.