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Seed major and minor axes of three canola varieties with high oil content (45H29 at 8%, 10%, and 12% moisture content wet basis, and Invigor 5440 and Nex4 105 at 10% moisture content) and one low-oil canola variety (5525 Clearfield at 10% moisture content) were measured at room temperature. Bulk density, angles of repose, and coefficients of friction against four structural surfaces were determined for two varieties of high-oil canola (Invigor 5440 and Nex4 105) and for mixtures of them (at ratios of 1:1, 1:2, and 2:1) at four moisture contents (8%, 10%, 12%, and 14%). The same physical properties were determined for the third high-oil canola (45H29) and for the low-oil canola (5525 Clearfield) at three moisture contents (8%, 10%, and 12%). The four structural surfaces were galvanized steel, plywood, wood-floated concrete, and steel-troweled concrete. Major and minor axes of 45H29 increased with increasing moisture content. Oil content did not affect the axes of canola seeds. Bulk densities were significantly different between Invigor 5440 and Nex4 105. Mixtures of the high-oil canola varieties had bulk density values between those of the canola varieties that were used in the mixtures. Bulk density decreased with increasing oil content. Angles of repose depended more on canola variety and surface properties than on oil content. The coefficient of friction against structural surfaces was not significantly affected by moisture content but was affected by oil content. Bins used to store low-oil canola could also be used to store high-oil canola. [ABSTRACT FROM AUTHOR]

Thermal conductivity of canola seeds is used as an engineering parameter in the design of processing, storing, drying, and cooling systems. Loose (standard) and compacted bulk densities, germination, and thermal conductivity of 5.5%, 7.5%, 9.5%, 11.5%, 13.5%, and 15.5% moisture content (wet basis) of canola (cultivar NX4-105 RR with 45.4% -419.4% oil content) seeds stored at 30°C for 0 d, 30 d, and 60 d were measured at -20°C, -10°C, 0°C, 10°C, 20°C, and 30°C. Moisture content of the canola seeds had a larger influence on the value of standard bulk density than temperature. The canola seeds with different storage times could be compacted by 5.1% ± 0. 6%. The mean of thermal conductivity of the 0 d canola seeds was 0.08684 W m-1 K-1. The thermal conductivity of 0 d canola linearly increased with increasing moisture content or temperature. The thermal conductivity, standard bulk density, and germination of the canola seeds significantly decreased with increasing storage time at 30°C, and a linear relationship was observed between the percentages of decreased standard bulk density, seed germination, and thermal conductivity. There was no significant difference in thermal conductivity of the canola seeds under loose and compacted conditions. [ABSTRACT FROM AUTHOR]

In this study, temperature rise and non-uniformity of heating of grain with different moisture contents after microwave treatment were investigated. The temperature anomalies after microwave treatment were measured for barley and wheat at four moisture levels (12, 15, 18, and 21% wet basis) and for canola at five moisture levels (8, 12, 15, 18, and 21% wet basis). Fifty grams of grain samples were heated in a laboratory scale, continuous-type, industrial microwave dryer (2450 MHz) at five power levels (100, 200, 300, 400, and 500 W) and two exposure times (28 and 56 s). Grain samples were thermally imaged using an infrared thermal camera as soon as they came out from the microwave chamber. Average, maximum, and minimum temperatures were extracted from each thermal image and the difference between maximum and minimum temperatures (ΔT) was calculated. The grain type had significant effect on the surface temperatures after microwave treatment. The surface temperatures increased with microwave powers and exposure times but decreased with moisture content. The average surface temperatures after microwave treatment were between 72.5 and 117.5°C, 65.9 and 97.5°C, and 73.4 and 108.8°C for barley, canola and wheat, respectively, when the applied microwave power was 500 W. At the same power level, the maximum surface temperature was between 100.3 and 140.0°C, 77.8 and 117.7°C, and 98.3 and 130.9°C for barley, canola, and wheat, respectively. Non-uniform heating patterns were observed for all three grain types at all moisture contents, power levels, and exposure times. The ΔT was in the range of 7.2 to 78.9°C, 3.4 to 59.2°C, and 9.7 to 72.8°C for barley, canola, and wheat, respectively. The location of hot and cold spots may vary in different dryers based on the position of magnetron and other components, but almost similar non-uniform heating pattern is expected in all microwave dryers. Therefore, this non-uniformity must be taken into consideration while developing microwave processing systems for grains. [ABSTRACT FROM AUTHOR]

Safe storage guidelines for grains at different moisture contents and storage temperatures are essential to know how long seed can be held without deterioration. Rye samples with 10.0, 12.5, 15.0, and 17.5% moisture content (wet basis) were stored at 10, 20, 30, and 40°C for 16 weeks. Germination, moisture content, visible and invisible microflora, and free fatty acid (FFA) values were monitored periodically. Germination rate decreased significantly with increase in moisture content, temperature, and storage period (α=0.05). Moisture content of the samples stored at 10°C increased with time, whereas that of samples stored at 30 and 40°C decreased. Visible mold appeared in all the 17.5% moisture samples and in all the samples stored at 40°C. Penicillium spp. and Aspergillus glaucus group were the predominant fungi in almost all samples throughout the study. Fat Acidity Value (FAV) increased with increasing moisture content, temperature, and storage time (α=0.05). Safe storage guidelines with respect to initial moisture content and temperature were developed based on the drop in germination and appearance of visible mold. Rye with ≤12.5% moisture content stored at ≤20°C would be safe for at least 15 weeks, whereas rye with ≤ 15% moisture content stored at 40°C would have less than a week to complete drying and cooling. [ABSTRACT FROM AUTHOR]

An infrared thermal imaging system was assessed for its capability to identify eight western Canadian wheat classes. Twenty-gram wheat samples at 14% moisture content (wet basis) were spread in a 100 x 100 mm monolayer and heated by a plate heater (maintained at 90°C) placed at a distance of 10 mm front the grain layer. The surface temperatures of the top surface of the grain bulk were imaged before heating, after heating for 180 s, and after cooling for 30 s using a thermal camera (n = 100 samples in each class). Temperature rise (after heating) and drop (after cooling) were significantly different for wheat classes (α = 0.05). Wheat samples were classified with twelve derived thermal features using statistical classifiers. Overall classification accuracies of an eight-class model, red class model (four classes), white class model (four classes), and pairwise comparison (two-class model) using a quadratic discriminant method were 76%, 87%, 79%, and 95%, respectively. The thermal imaging approach may have potential to develop class identification methods in wheat handling facilities. However, further investigations are required to determine the performance of this system for wheat samples mixed with defects, with different moisture contents, and grown in different locations and years. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) spin-echo magnetic resonance imaging (MRI) was used to explain the moisture movement in single wheat kernels prior to and during drying. Drying was performed at temperatures of 40 °C and 50 °C using heated N2 gas at a velocity of 0.23 m/s. Individual wheat kernels of 20% to 64% moisture content (wet mass basis) were dried to study the moisture movement inside the kernel during drying. MR images were recorded at equal time intervals during drying. Moisture distribution and transfer were analyzed from MR images of wheat kernels obtained before and during drying. Moisture distribution was non-uniform at an equilibrium state prior to drying. Further, moisture loss from the seed parts differed significantly during drying. The MR images were used to obtain the drying rates and patterns of water in wheat kernels during the drying process. Influence of grain parts on the moisture distribution was also studied using mechanically scarified kernels and germ-removed kernels. [ABSTRACT FROM AUTHOR]