An apparatus for non-destructive measurement of internal properties of individual vegetable or fruit pieces comprises: LEDs constructed and arranged to emit radiation into a vegetable or fruit product; pick-up structure constructed and arranged to pick up radiation, emitted by the LEDs, that has entered the vegetable or fruit product and then exited the vegetable or fruit product; a hollow cylinder between the LEDs and the pick-up structure for preventing radiation emitted by the LEDs from directly reaching the pick-up structure; a spectrometer; structure for conveying to the spectrometer the radiation picked up by the pick-up structure; and structure for processing a spectrum frequency and amplitude data as produced by the spectrometer upon the radiation picked up by the pick-up structure being analyzed by the spectrometer.