The effects of the drying temperature and the residual moisture content on the drying behavior, energy consumption and quality of dried citrus peels (CPs), which are value-added food ingredients, were studied. The CP samples were dried in a laboratory-scale hot-air dryer at air temperatures from 40 to 70 °C under a constant air velocity of 1 m/s until the desired moisture content for safe storage was reached or until the final moisture level was achieved for the specific drying conditions. Cakes prepared from blends containing different proportions (0 %, 10 %, 15 % and 20 %) of dried CPs were also evaluated for chemical composition and sensory attributes. The optimal drying temperatures were 50–60 °C, and the optimal moisture content was 10±0.2 % w.b.; these conditions reduced the drying time and energy consumption and maximized the product quality. In contrast, over-drying CPs with the higher temperatures and to a final moisture level of 5.4±0.2 % sharply increased the loss of vitamin C, carotenoids as antioxidants and essential oils. Incorporation of 15 % dried orange and mandarin peels in cake formulas increased the dietary fiber by 33.5 % and 29.6 %, the crude fat by 2.9 % and 4.6 % and the ash by 30.6 % and 29.0 %, respectively, whereas the protein and total carbohydrate content decreased slightly. Highly acceptable nutritious cakes could be obtained by incorporating 15 % orange or mandarin peel dried to 10 % w.b. moisture content into the formulation.

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Stress cracking of two corn hybrids (White, SC-10 and Yellow, SC-162) dried at various temperatures (35, 50, 60, 75 and 100 o C) from 21.2% to 13% moisture content and tempered for 24hr at ambient temperature (22  1 o C with available relative humidity) were tested. A breakage tester (BT-drop tester) was manufactured and a single-grain breakage susceptibility of two corn hybrids at various grain temperatures and times after drying (0, 3 ,6 , 10, 20 and 30min) were evaluated. The results indicated that, the damage index significantly increased as the drying temperature increased for two corn hybrids except at 100 o C with SC-162, it was decreased. The SC-162 was more susceptible to cracking more than SC-10 hybrid especially at lower grain temperature. Also, the predicted models and observation showed that both hybrids were plastic and had minimal breakage susceptibility at high grain temperatures from 72 to 93 o C, while, decreasing grain temperature increased breakage exponentially. After drying at both 75 and 100 o C, the breakage of the two corn hybrids increased rapidly for the first 10min after drying and reached an asymptotic level after around 10min cooling after finishing drying at ambient temperature. At the same drying temperature (75 o C), the breakage susceptibility increased by 37.4% for SC-10 and by 51.5% for SC-162 with the average stress cracks (multiple and checked) kernels for two hybrids of about 20.2%.

Development and testing an expeller machine for oil extraction as a dual purpose for forming rice bran pellets to maximize the oil extraction rate during solvent extraction was carried out. Four screw revolving speed (0.262, 0.524, 0.786 and 1.05 m/s), three die hole diameter (6, 8 and 10 mm) as well as three levels of moisture content (11.1, 14.2 and 16.1%, w.b.) of two rice bran components (white and dark bran) during extrusion process were used to investigate their effect on the machine performance and the resulting extrudate properties. The results revealed that, the extruder productivity of white bran at the same die hole diameter (10 mm) was increased by 30.