The knowledge on existing relationship among the mass, length, width, thickness, volume and projected areas of fruits is useful for proper design of processing equipment especially grading machines. This study determined the basic physical properties of date fruit (Mazafati variety) during different ripening stages (Kimri, Khalal, Rutab and Tamr). The suitable model for predicting mass was the developed by fitting the measured physical properties with four models, including Linear, Quadratic, S-curve, and Power. The results of the study showed statistical significance among measured physical properties at the 1% probability level. According to the results obtained, the mass model based on actual volume was more accurate. However, measurement of dimension (s) and projected area (s) are far easier and reasonable than that of actual volume of date. To conclude, the mass model on the basis of length of date fruit is recommended: M = 0.034L2- 1.878L+32.42, R2 = 0.98, SEE =0.005.

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