Lighting preferences of Iberian sausages for Spanish observers

Abstract

We report results of a visual experiment performed by 20 adult Spanish observers using calibrated images of 18 samples of sliced Iberian sausages under 15 illuminations, including 8 illuminants proposed by the International Commission on Illumination (CIE) and 7 light sources found in meat sections of supermarkets in Spain and Japan. Visual results from the pair comparison and magnitude estimation psychophysical methods used in our experiment showed a high correlation (Pearson’s linear correlation coefficient r = 0.915). Illumination strongly influenced color preferences of sliced Iberian sausages. For example, using the magnitude estimation method, the average lighting preferences changed about 2.8/10 for the 15 illuminations tested. There were no statistically significant differences between lighting preferences for different kind of sausages. Exploring quality indices of white lights, we found that the correlated color temperature and gamut area index (Color Res. Appl. 33, 192-202, 2008) provided the highest linear correlations with visual preferences in our current experiment. Lights with correlated color temperatures below 3000 K or gamut area indices below 70 were not preferred. The CIE general color rendering and color fidelity indices provided poor predictions of visual preferences in our current experiment.