Selection of light source to improvement fruit satisfaction

Abstract

How to choose lighting source to enhance a gratifying ambience so as to improve impression and evaluation of the fruits was investigated in this study. Firstly, a laboratory functioning with controllable LED light source and physical quantity measurement was constructed. Secondly, subjective visual satisfaction experiments on the testees with LED light source combining with different color temperature, illumination and color rendering thus to probe into people's psychological feeling on the fruit taste were conducted. Thus, experimental design adopting Taguch method to map out 9 groups of light source condition with three fruits (red-apple, blue-grape and green-guava), three color temperature (2700, 4200 and 6000 °K), three color rendering (70, 80 and 90 CRI) and three illumination (750, 1200 and 1500 Lux). Then, conjoint analysis approach was applied to evaluate the main effect of each light source attribute and find out the corresponding LED light sources of best psychological feeling for the representative three fruits. The experimental analysis results showed that the light source condition for the best testees' overall satisfaction on different fruits were successively represent as apple (red): color temperature 2700 (°K), color rendering 80(CRI) and illumination 1500(Lux); grape (blue): color temperature 4200 (°K), color rendering 70(CRI) and illumination 1200(Lux); and guava (green): color temperature 6000 (°K), color rendering 80(CRI) and illumination 1500(Lux). These results can be provided as references for lighting designers and businessmen of vegetables and fruits, performed as the basis of illumination condition improvement, thus to enhance people's overall satisfaction presented by vegetables and fruits.