Figure 1 : Schematic illustration of hyperspectral reflectance imaging system . Courtesy : Tan et al . ( 2018 ).
bananas during storage , estimating the moisture content of sweet potatoes during the drying process ( see Figure 2 ), differentiating seeded and seedless watermelons during the sorting and grading process and recently , determining the maturity level of oil palm fresh fruit bunches ( FFB ). Other imaging techniques such as thermal imaging have been adopted for monitoring the surface temperature of carrots in real time during steam treatment ( see Figure 3 ) while fluorescence imaging has been successfully used for monitoring the quality of tomatoes during storage .
Spectroscopy Techniques
Spectroscopy provides a precise analytical method for finding the constituents in a material that can be used to evaluate the characteristics and quality of agricultural products . The spectroscopy technique measures the aggregate amount of light varying from visible ( Vis ) to near-infrared ( NIR ), either reflected from or transmitted through a biological material , resulting from the combined effect of absorption and scattering of photons by the tissues , which produces spectral data .
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