M.A. Thesis:

Evaluation of some physical and mechanical properties of almonds cultivars (Deime Sheshtamad Sabzevar, Shokofe karkhane ghande Jovin and deime Khoshab) at different humidity levels

Determining the physical and mechanical properties of agricultural products, as a basis for the design and manufacture of machinery and equipement of transfer, grading and processing of agricultural products, has always been an important issue. In this study, some physical and mechanical properties of dryland almonds of Sheshtamad in Sabzevar, bloosom of Jovein sugar factory and dryland of Khushab and their brains, was evaluated that including the average of length, width, thickness, volume, mass, bulk density, particle density, porosity, sphericity, the average of geometric and arithmetic of diameter and the angle of full and discharge repose, the coefficient of static friction and tissue in three different moisture levels. Then, the effect of moisture content, on the perfect almonds and their brains, were studied. The results showed that, with increasing moisture content of almonds and their brains, length, width, thickness, volume, mass and sphericity and the average arithmetic and geometric diameter, the percent of porosity, angle of full and descharge repose and friction, was increased at all levels, while the amount of hardness and bulk density was reduced. The particle density, was increased for almonds with the skin, but for almond brains, was reduced. Among of three varieties of studied almonds, Khushab type had greater length and width than the other two types and Sheshtamad almond, had the minimum length, width and thickness and had the most sphericity. The least amount of sphericity was related to Khushab almond and the most amount of thickness was related to the almond of sugar factory and the almond varieties of Sheshtamad had the lowest average diameter of the arithmetic and geometry, among of the other varieties that were investigated. Also, almond varieties of sugar factory showed the highest geometric average diameter and almond varieties of Khushab showed the highest aritmetic average diameter. Among of almond varieties that were studied, the highest and lowest mass and volume, respectively, related to the sample of Khushab almonds and Sheshtamad almonds. The most real density and bulk density, respectively related to the almond varieties of Sheshtamad and almond varities of Khushab and the lowest real density and bulk density, related to almond varieties of sugar factory. Sheshtamad almond varieties, showed the highest porosity and Khushab almond varieties, showed the lowest porosity. In general, the maximum amount of full and discharge angle of repose was obtained for almond varieties of sugar factory and the lowest amount of full and discharge angle of repose, was obtained for Sheshtamad almond varieties. In general, Sheshtamad almond varieties, at all studied levels, almond varieties of sugar factories respectively had the lowest and themost amount of coefficient friction. According to the results of texture analysis, almond varieties of sugar factory and almond varieties of Sheshtamad were showed respectively the lowest and the most hardness. Key words: physical properties, almond, almond brain, moisture content

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