Estimating Sensory Properties with Near-Infrared Spectroscopy: A Tool for Quality Control and Breeding of ‘Calçots’ (Allium cepa L.)

Abstract

Using trained panelists to evaluate sensory attributes is unfeasible when many samples must be evaluated, such as in quality control or breeding programs. Near-infrared spectroscopy (NIRS) is a rapid inexpensive method often used in food quality evaluation. We assessed the feasibility of using NIRS to estimate sweetness, fiber perception, and off-flavors, the most important sensory attributes in cooked ‘calçots’ (the immature floral stems of second-year onion resprouts). The best results were achieved through models using interval partial least squares (iPLS) variable selection on spectra from pureed cooked ‘calçots’, which yielded values of the ratio of performance to deviation (RPD) greater than 1.4 in all cases. Therefore, it would be feasible to use NIRS to estimate sensory properties in ‘calçots’. This approach would be useful in initial screening to discard samples that differ substantially from the ideotype; thus, sensory analysis by trained panels could be reserved for finer discriminations.