The derivative pre-treatments applied, i.e. first or second derivative,
provided in general calibrations with similar predictive ability,
i.e. no significance differences were detected, a finding also
reported by Fernández-Cabanás et al. (2007). Nevertheless, for palmitic
and stearic acids the best results were obtained with the first
derivative of the spectral data, while for oleic and linoleic, depending
on the analysis mode used, the best results were produced by
one or other derivative order treatment.