NONDESTRUCTIVE PULP AND SEED MEASUREMENTS OF LITCHI USING MAGNETIC RESONANCE IMAGING

Whole-fruit magnetic resonance imaging (MRI) was performed on sixteen ripened ´Bengal´ litchi with the Varian 2 Tesla NMR tomograph fitted with a 8 cm diameter birdcage coil, and operating at proton resonant frequency of 85.5 MHz. Three MRI of each litchi were made in the sagital, coronal and transverse orientations. After imaging each litchi was weighed and peeled. Peel, pulp and seed were weighed. MRI slices of fruit were acquired and evaluated using SIARCS image processing software (Jorge and Crestana, 1996). MRI of pulp and seed were segmented in black and white images to measure area which were then correlated with their respective weights. The correlation of pulp weight (g) vs. area (cm²) for sagital, coronal and transverse images were R²=0.8695, R²=0.8057 and R²=0.7400, respectively. The correlation of seed weight (g) vs. area (cm²) for these images were R²=0.5472, R²=0.5496 and R²=0.8948, respectively.