. Multi-spectral reflective image a

. Multi-spectral reflective image analysis was applied tomonitor the evolution and spoilage of leafy spinach covered byplastic materials (Lara et al., 2013). In detail, the leaves were placedinside plastic Petri dishes which were covered with three differentplastic materials to compare the optical behaviour of the mostcommonly used packaging. It is important to note that, in such asituation, the plastic formed a regular planar surface: its interactionwith the light (traversing the plastic both when going from thelamp to the product and from the product to the sensor) mainlyreduced the measured spectra, affecting each wavelength on thebase of the optical properties of the material. No reflection of otherkinds of distortion were present, due to the controlled relativegeometry among Petri dish, lamp and detector.