Near-Infrared spectroscopy (NIRS) analysis of intact olive fruit: an useful tool in olive breeding programs

Abstract

The objective of this study was to evaluate the potential use of Near-Infrared Spectroscopy (NIRS) for the analysis of oil content, moisture and fatty acids composition in intact olive fruit. A total of 287 samples, each from a single plant from an olive breeding program, were scanned by NIRS between 400 and 1700 nm. Partial least squares (PLS) regression was used to create calibration models (with 70 % of samples) relating laboratory reference values to spectral data (original, first and second derivative spectral data). The best equations obtained were validated (with 30% of samples) showing values of r² of 0.88 % for the moisture, 0.83 % for oil content, 0.77 % for oleic acid content and 0.81 % for linoleic acid content. Therefore a reliable and accurate preselection can be made by using NIRS for both oil content and oleic acid content, with a nondestructive analysis, in a few seconds and without use neither production of chemical reagents.