The influence of different pretreatment conditions and moisture content of flaxseed prior to pressing was studied on the screw press performance. Oil recovery, residual oil in cake, press rate and sediment content were measured as a function of pretreatments and moisture content for screw pressing of flaxseed. The pretreatments had significant effect on residual oil and press rate but nonsignificant effect on oil recovery and sediment content. An inverse relationship between seed moisture content and oil recovery was observed in pressing flaxseed that means decreased moisture content in the range of 13.8 to 6.5% resulted increased oil recovery from 44.4 to 73.3%, 36.4 to 76.6% and 45.4 to 81% for the only moisture conditioned, steam‐ and enzyme‐treated seeds, respectively. The residual oil decreased significantly with decrease in moisture content from 13.8 to 6.5% while the press rate and sediment content were not affected significantly with decreased moisture content. Therefore, pressing of flaxseed at lower moisture content appears to offer more benefits rather than other pretreatments, steam and enzyme treatments attempted in this study. PRACTICAL APPLICATIONS The screw presses are used for the small scale processing of flaxseed. The performance of the screw presses could be improved by selection of appropriate pretreatments prior to screw pressing. Hence, the information generated in this study would directly benefit the processors in selection of pretreatment conditions for better screw press performance. It would also be useful for the researchers to have better understanding of screw pressing under different pretreatment conditions.

A b s t r a c t. Physical properties of coriander seeds were determined at moisture content of 3.5-17.7%, d.b. The major axis and 1 000 seeds mass were found to decrease nonlinearly with increase in seed moisture. The medium and minor axes, geometric mean diameter, sphericity, unit volume, surface area and angle of repose increased linearly. Bulk density decreased linearly, however the true density increased non-linearly. The coefficient of static friction increased nonlinearly for different surfaces with increase in moisture level and its maximum was found for plywood surface. The rupture force and energy absorbed decreased linearly with increasing moisture content.K e y w o r d s: coriander, seed, physical properties, moisture content INTRODUCTION Coriander (Coriandrum sativum L.) is an annual herb from the family Apiaceae and native to southern Europe and North Africa to southwestern Asia. The coriander seeds are almost ovate globular and there are many longitudinal ridges on the surface. Data concerning the physical and mechanical properties of agricultural food materials are of importance to plant breeders, engineers, machine manufactures, food scientists, processors and consumers. Those properties are useful in postharvest unit operations for the design of cleaning, grading, sorting, transportation, handling, aeration, sizing, storing, size reduction, packaging and other processing equipment (Sahay and Singh, 2001). Several investigators have reported the moisture dependence of physical and mechanical properties of chosen agricultural materials ie for black pepper (Murthy and Bhattacharya, 1998), fenugreek (Altuntas et al., 2005); fruit and kernel (Sahoo et al., 2009); rapeseed (Izli et al., 2009); bay laurel seeds (Yurtlu et al., 2010); lentil seed (Bagherpour et al., 2010). Chang (1988) determined the density and porosity of grain kernels using a gas pycnometer. Coskuner and Karababa (2007) determined some physical properties of coriander seeds at different moisture content and reported that the axial dimensions, sphericity, seed volume and surface area, true density, angle of repose, 1 000 seeds mass and coefficient of static friction increased with increase in moisture content except for bulk density.The present work was carried out to understand the physical and mechanical properties of coriander seeds at different moisture content. MATERIALS AND METHODSCoriander seed (RCR-4) was procured from the National Research Centre for Seed Spices, Ajmer (India). The seeds were cleaned manually and broken, and foreign matter, split, deformed and immature seeds were discarded before the samples were prepared for the experiment. The initial moisture content of seed was determined by vacuum oven method (Ranganna, 1986) at 80°C and pressure of 13.33 KPa. The seeds were stored at room temperature (25°C) for 2 to 3 weeks. Initial moisture content of coriander seed was found to be 7.0% d.b. For experimentation, a predetermined quantity of coriander was dried in a tray dryer at 55°C to achieve a desired low moisture c...

Effects of moisture content and residence time on various dehulling parameters of flaxseed including yield, hull, hullability, extraction rate and embryo (dehulled flaxseed) recovery were studied. A laboratory model rice polisher/ dehulling machine and a laboratory model aspirator were used for dehulling and aspiration (hull separation), respectively. The dehulling experiments were carried out for moisture contents ranging from 1.9 to 7.8% wb and residence times from 20 to 50 sec in dehulling machine at 2000 rpm of abrasive disc (rotor) of the polisher. Both moisture content and residence time played an important role in dehulling of flaxseed. The optimum moisture range and residence time for dehulling of flaxseed were 1.9 to 4.5% wb and 40 sec, respectively.

Proper utilization of water is essential particularly in arid and semi-arid areas. Mulching is an application of any plant residues or other materials for covering top soil surface for conserving soil moisture, reducing the runoff and thereby to control soil erosion, checking weed growth, improving soil temperature, modifying the micro environment of soil to meet the needs of seeds for their good germination and better growth of seedlings. This study was conducted in the field located in South Pangabri area near Rain-out shelter of Pusa Farm Samastipur, Bihar located in North Bihar, India. The RBD (Randomized Block Design) was considered for design of experiment. It investigated the effects of rate of organic mulches (Sugarcane leaf & Paddy straw) on soil moisture conservation and on initial growth of Maize crop with different treatments T1 (No mulch), T2 (Paddy straw @ 3 t/ha), T3 (Paddy straw @ 6 t/ha), T4 (Paddy straw @ 9 t/ha), T5 (Sugarcane leaf @5 t/ha), T6 (Sugarcane leaf @10 t/ha), T7 (Sugarcane leaf @15 t/ha). The observations on soil moisture contents were taken from each treatment, replication-wise on alternate-day basis for four weeks period. The soil moisture content was determined by using oven drying method. Amongst different treatments, T6 is found most effective to conserve the highest level of moisture content in soil. The level of moisture conservation in this treatment (T6) was found to the tune of about 20.17% (dry basis).