A b s t r a c t. Some moisture-dependent physical properties of Christmas Lima were investigated. Results of experiments on rewetted Christmas Lima bean seed showed increasing in length, width, thickness, geometric mean diameter, volume, sphericity, mass, 1 000 seeds mass, projected area and terminal velocity. A decreasing trend for bulk density and true density was observed. Both static and dynamic coefficients of friction increased as the moisture content increased. The highest static (0.59) and dynamic coefficients of friction (0.34) were found on the rubber surface. The average rupture force, rupture deformation and rupture energy were investigated under compression loading. These characteristics were determined as functions of moisture content, compression orientations and deformation rates. At all deformation rates, rupture deformation and rupture energy of the Christmas Lima bean generally increased with increase of moisture content. Moreover, rupture force decreased for compression along the X-and Y-axis.K e y w o r d s: Christmas Lima bean, moisture content, physical properties

Grading fruits based on mass is important in packaging and reduces the waste, also increases the marketing value of agricultural produce. The aim of this study was mass modeling of two major cultivars of Iranian limes based on engineering attributes. Models were classified into three: 1-Single and multiple variable regressions of lime mass and dimensional characteristics. 2-Single and multiple variable regressions of lime mass and projected areas. 3-Single regression of lime mass based on its actual volume and calculated volume assumed as ellipsoid and prolate spheroid shapes. All properties considered in the current study were found to be statistically significant (ρ < 0.01). The results indicated that mass modeling of lime based on minor diameter and first projected area are the most appropriate models in the first and the second classifications, respectively. In third classification, the best model was obtained on the basis of the prolate spheroid volume. It was finally concluded that the suitable grading system of lime mass is based on prolate spheroid volume.

Eggplant has a very limited shelf life and, like other vegetables, is susceptible to different types of damage during and after harvest operations. Besides, according to the inner construction of eggplant fruit, it can be regarded as an inhomogeneous system. It is therefore important to specify how storage might affect their mechanical properties and how they vary in morphology.In this work, eggplants were divided into three portions along the longitudinal axis and their textural properties were separately investigated using different types of test over a 10-day period of storage at ~11˚C and ~90% relative humidity (RH). The results showed that the tension strength, rupture force and Young's modulus of skin tissue decreased with increasing the length of storage period, and they were generally different in the different portions of the fruit that were sampled as these properties in the upper section were larger than those of the middle and bottom sections. The values of Young's modulus and rupture force of pulp tissue taken from compression tests decreased from 1.466 to 0.821 MPa and 20.70 to 17.66 N for upper section, 0.637 to 0.536 MPa and 15.33 to 13.13 N for middle section and 0.518 to 0.422 MPa and 14.19 International Journal of Food Properties A c c e p t e d M a n u s c r i p t 2 to 12.19 N for bottom section, respectively with the increase in storage period. Similarly, as the samples were stored longer, the Young's modulus and rupture force of their combined skin and pulp tissues, obtained from penetration tests, decreased from 3.01 to 2.02 MPa and 31.21 to 24.95 N for upper section, 2.59 to 1.66 MPa and 28.64 to 21.66 N for middle section and 1.91 to 1.15 MPa and 23.18 to 17.37 N for bottom section, respectively. It was concluded that the mechanical resistance noticeably decreased towards the bottom third of the fruit.

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Effect of coating with calcium nitrate in three concentrations (0.0, 0.5, and 1.0 wt%) on chemical and mechanical properties, and impact behaviour of two apple cultivars (Golden Delicious (GD) and Red Delicious (RD)) during time (0, 2, and 4 months) was studied. Moisture content, pH, titratable acidity, °Brix, organoleptic properties, modulus of elasticity (E), yield stress, yield strain, and toughness were measured. The effect of impact loads was determined by measuring bruise volume (BV) and bruise susceptibility (BS). The results showed that pH and °Brix significantly increased, while titratable acidity, E, yield strain, toughness, and BV decreased during storage time. As Ca(NO3)2 concentration increased, titratable acidity, E, yield strain and yield stress increased and pH decreased (P < 0.05). Highest and lowest values for °Brix were observed in GD treated with 1.0% Ca(NO3)2 after four months (13.31) and GD treated with 0.5% Ca(NO3)2 at the first day (10.65), respectively. Maximum E was obtained in GD treated with 1.0% Ca(NO3)2 on the first day (2130 kPa) and this sample also showed the lowest BS after four months of storage (2.82 mL J−1), while the uncoated GD had the highest BS on the first day (7.11 mL J−1).