R. Goodacre et al., RAPID ASSESSMENT OF THE ADULTERATION OF VIRGIN OLIVE OILS BY OTHER SEED OILS USING PYROLYSIS MASS-SPECTROMETRY AND ARTIFICIAL NEURAL NETWORKS, Journal of the Science of Food and Agriculture, 63(3), 1993, pp. 297-307
Curie-point pyrolysis mass spectra were obtained from a variety of ext
ra-virgin olive oils, prepared from various cultivars using several me
chanical treatments. Some of the oils were adulterated (according to a
double-blind protocol) with different amounts of seed oils (50-500 ml
of soya, sunflower. peanut, corn or rectified olive oils per litre of
mixed oil). Canonical variates analysis indicated that the major sour
ce of variation between the pyrolysis mass spectra was due to differen
ces between the cultivars, rather than whether the oils had been adult
erated. However, artificial neural networks could be trained (using th
e back-propagation algorithm) successfully to distinguish virgin oils
from those which had been adulterated.