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20132
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End date: 2013 × Start date: 2013 × Thesis Type: M.Tech ×
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    ThesisItemOpen Access
    PROCESS OPTIMIZATION FOR EXPRESSION OF OIL FROM DEHULLED SUNFLOWER (Helianthus annuus L.) SEEDS
    (PAU Ludhiana, 2013) Arul Selvam T; Tarsem Chand
    Mechanical expression of oil from dehulled sunflower seed is highly desirable as it provides, at low cost, non-contaminated, nutritionally rich press cakes which can be processed into nutritious edible foods. Unfortunately, mechanical oil extraction process suffers from certain drawbacks. The dehulled sunflower seeds obstruct forward movement inside the expeller barrel due to the absence of hull portion and less friction. The main focus of the present study was to maximize the oil recovery and obtain nutritionally rich press cakes from dehulled sunflower seeds using mechanical oil expression. Physical and mechanical properties were studied under four different moisture content ranged from 6-18 % (d.b.). The results showed that the geometric mean diameter, surface area, volume, sphericity and aspect ratio, thousand seed/kernel weight, true density, porosity, the angle of repose, static coefficient of friction and rupture energy were found to be increasing linearly for seed and kernel. Whereas bulk density, initial cracking force and mean rupture force decreased linearly with the increase of moisture content for both seed and kernel under study. Pre treatments in the form of steaming and addition of bio-based friction materials such as rice bran and wheat bran at different levels were employed. Central composite rotatable design was used to generate a set of experiment at different pretreatment levels during oil expression. A statistical model predicted the maximum oil yield efficiency, maximum protein, minimum fibre, minimum residual oil, minimum chlorogenic acid, minimum free fatty acid and minimum peroxide value of dehulled sunflower oil and press cakes at these optimized variable conditions for rice bran incorporation: steaming time of 10 min, steaming pressure of 0.5 kg cm-2 and rice bran incorporation of 13.88g 100g-1 of dehulled sunflower seed. For wheat bran incorporation it was at steaming time of 15 min, steaming pressure of 1.00 kg cm-2 and wheat bran incorporation of 15g 100g-1 of dehulled sunflower seed. Using these variables results are validated under experimental condition in three independent replicates. Rice bran incorporated oil expression gave best results with high desirability value.
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    Studies on effect of blade shape and rotor speed of rotavator on pulverization and mixing quality
    (PAU Ludhiana, 2013) Shiva Bhambota; G S, Manes
    A study was conducted at Punjab Agricultural University, Ludhiana to evaluate the performance of commercially available rotavator blade shapes to find out the best combination of blade shape and rotary speed of rotavator for tillage and mixing operations. Experiments were conducted on three blade shapes (L, C and J) at three rotor speeds (180, 215 and 250 rpm) in two types of soils S1 (sand 75.5%, silt 12.4% and clay 12.1 %) and S2 (sand 24.2%, silt 34.8% and clay 41%) to study the effect of blade shape and rotor speed on pulverization index, mixing index, percent reduction in bulk density and fuel consumption. These treatment combinations were compared with control (Pulverization with single pass of disc harrow followed by single pass of cultivator). For measuring pulverization index, soil samples were taken after single pass of rotavator. Standard sieve analysis method was used to find the mean mass diameter (MMD) of sample soil particles for mixing of crop mass after the operation of rotavator, the pieces of the crop which were exposed to 1/3rd of their length or more were collected and weighed to find mixing index. Percent reduction in bulk density before and after treatment by rotavator was calculated using core sampler method for pulverization and mixing operation. For measuring the fuel consumption; fuel flow meter was installed in the fuel line of the tractor. The results for each dependent parameter (pulverization index, mixing index, percent reduction in bulk density and fuel consumption) were analyzed on the basis of Completely Randomized Design (CRD) test using software “CPCS 1”. J shape blades gave minimum pulverization index (3.06 and 8.57 mm) and maximum mixing index (80.72 and 91.43 %) at 250 rpm rotor speed as compared to L and C shaped blades and control for both soils S1 and S2 respectively. The average fuel consumption was maximum for J shape blades followed by L and C shape blades respectively for both pulverization and mixing in both soil types. C shape blades have minimum fuel consumption as compared to other two blade shapes for both types of soil for pulverization and mixing operation respectively. So, J shape blade at 250 rpm rotor speed can be considered as the best combination for pulverization and mixing.