Some physical properties of sugarbeet seed

Various physical properties of sugarbeet seed were determined as a function of moisture content. The lengths of the major, medium and minor axes varied from 4.61 to 5.30, 3.82 to 4.36 and 2.20 to 2.38 mm, respectively, as the moisture content increased from 8.4 to 14.0% d.b. In the same moisture range, the arithmetic and geometric mean diameters increased from 3.54 to 4.02 and 3.38 to 3.80 mm, respectively. Studies on rewetted sugarbeet seed showed that the sphericity decreased from 0.734 to 0.717, whereas thousand seed mass and projected area increased from 12.60 to 13.41 g and 12.1 to 15.6 mm², respectively, with increase in moisture content from 8.4 to 14.0% d.b. The bulk density, true density and porosity decreased from 447 to 418 kg m⁻³, 962 to 851 kg m⁻³ and 53.6 to 50.9%, whereas terminal velocity and angle of repose increased from 5.6 to 6.6 ms⁻¹ and 17.6 to 25.0°, respectively, as the moisture content increased from 8.39 to 14.00% d.b. The static coefficient of friction increased on four structural surfaces namely, rubber (0.687-0.790), plywood (0.480-0.608), galvanised metal (0.392-0.434) and aluminium (0.279-0.388) in the moisture range from 8.4 to 14.0% d.b.     

Predicting Guar Seed Splitting by Compression between Two Plates Using Hertz Theory of Contact Stresses

Hertz's theory of contact stresses was applied to predict the splitting of guar seeds during uni-axial compressive loading between 2 rigid parallel plates. The apparent modulus of elasticity of guar seeds varied between 296.18 and 116.19 MPa when force was applied normal to hilum joint (horizontal position), whereas it varied between 171.86 and 54.18 MPa when force was applied in the direction of hilum joint (vertical position) with in moisture content range of 5.16% to 15.28% (d.b.). At higher moisture contents, the seeds yielded after considerable deformation, thus showing ductile nature. Distribution of stresses below the point of contact were plotted to predict the location of critical point, which was found at 0.44 to 0.64 mm and 0.37 to 0.53 mm below the contact point in vertical and horizontal loading, respectively, depending upon moisture content. The separation of cotyledons from each other initiated before yielding of cotyledons and thus splitting of seed took place. The relationships between apparent modulus of elasticity, principal stresses with moisture content were described using second-order polynomial equations and validated experimentally. Practical Application: Manufacture of guar gum powder requires dehulling and splitting of guar seeds. This article describes splitting behavior of guar seeds under compressive loading. Results of this study may be used for design of dehulling and splitting systems of guar seeds.     

Assessing mineral composition and morpho-physiological properties of de-hulled einkorn wheat during storage at different moisture levels

In this study were investigated the effects of different moisture levels (4.8, 9.5, 13, 16.7 and 20%, w.b.) during the storage at 10 °C for three months on some mineral compositions and morpho-physiological properties as dimensional (length, width, thickness, arithmetic mean diameter, geometric mean diameter, surface area and volume, sphericity), gravimetric (thousand grain weight, bulk and true densities) and the seed (colour measurement and electrical conductivity) of de-hulled einkorn wheat seeds. Mineral composition of wheat seeds changed with increasing moisture level. In particular, decreases in mineral composition were observed above 16.7% moisture level. Dimensional properties showed increases depending on increased moisture level. It was found that thousand grain weight and true density values increased with increase in moisture level. However, bulk density values were found to decrease with increase in moisture level. The seed colour properties as L*, a*, b*, Chroma, hue angle and Browning index did not change statistically at the end of three months storage with increase at moisture level. The results showed that mineral compositions and functional properties of seeds at moisture level of 9.5% is more suitable than other moisture levels. As a result, high moisture levels during storage can cause degradation of seed quality.     

Changes in some nutritional,bioactive and morpho-physiological properties of common bean depending on cold storage and seed moisture contents

Seed moisture content is one of the most important storage parameters affecting the quality of stored common beans. This study was conducted to investigate the changes in some nutritional, bioactive and morpho-physiological properties of common bean stored at three different seed moisture contents (6.4, 11.7 and 17.3%), 4 °C and 65% RH for 12 months. Significant differences were determined in terms of examined properties depending on different seed moisture contents before and after storage. Protein, essential mineral contents, total phenolic content, bulk density, true density and electrical conductivity decreased consistently as seed moisture content increases both before and after storage. On the contrary, dimensional properties, shape index values, thousand grain weight and total flavonoid content increased linearly with increase of seed moisture content both before and after storage. As a result, protein, essential mineral contents (potassium, magnesium, calcium, iron, zinc, manganese), antioxidant activity, total phenolic and total flavonoid content of common bean significantly decreased at the end of 12 months storage compared with before storage, while the contents of heavy metals such as Co, Sn and Pb increased after storage. In addition to, highly significant and positive correlations were determined between L* and WI, b* and C*, Dg and Da, Dg and Sa, Sa and Sv, P and K, P and Ca, ash and pH, Zn and Cu, Se and As. The results of this study clearly indicated that low seed moisture content was the most suitable to maintain the quality of common beans for long-term storage.     

Geometric and Mechanical Properties of Mung Bean (Vigna Radiata L.) Grain: Effect of Moisture

In this research, selected geometric and mechanical properties of mung bean grain were evaluated as a function of moisture content. Five levels of moisture content ranging from 7.28 to 17.77% d.b. (dry basis) were used. The average length, width, thickness, arithmetic and geometric mean diameters, sphericity, thousand grain mass and angle of repose ranged from 5.145 to 6.199 mm, 3.760 to 4.474 mm, 3.537 to 4.223 mm, 4.147 to 4.965 mm, 4.090 to 4.893 mm, 0.795 to 0.789, 52.3 to 64.6 g, and 25.87 to 29.38° as the moisture content increased from 7.28 to 17.77% d.b., respectively. The bulk density was found to be decreased from 821.3 to 745.2 kg/m³, whereas the grain volume, true density, porosity, terminal velocity, and projected area were found to be increased from 27.88 to 47.33 mm³, 1230.0 to 1456.7 kg/m³, 30.43 to 46.57%, 4.86 to 5.29 m/s, and 17.48 to 19.26 mm², respectively. There is a 43% increase in surface area from grain moisture content of 7.28 to 17.77% d.b. The static coefficient of friction on various surfaces increased linearly with the increase in moisture content. The rubber as a surface for sliding offered the maximum friction followed by galvanised iron, medium density fibreboard, stainless steel, aluminium and glass sheet. As moisture content increased from 7.28 to 17.77%, the rupture forces values ranged from 67.39 to 39.44 N; 63.86 to 42.18 N, and 53.96 to 41.79 N for thickness (Z axis), length (Y-axis) and width (X-axis), respectively.     

Moisture Dependent Physical Properties of Dry Sweet Corn Kernels

Physical properties of sweet corn kernels have been evaluated as a function of kernel moisture content, varying from 9.12 to 17.06% (db). In the moisture range, kernel length, width, thickness, and geometric mean diameter increased linearly from 9.87 to11.09 mm, 7.41 to 9.25 mm, 3.25 to 4.37 mm, and 6.18 to 7.62 mm, respectively, with increase in moisture content from 9.12–17.06%. The sphericity index, kernel volume, kernel surface area, and thousand seed weight increased linearly from 62.6 to 68.8, 93.8 to 194.3 mm³, 120.1 to 182.9 mm², and 220 to 268 gr, respectively. Apparent density and bulk density decreased linearly from 1.315 to 1.232 g/cm³ and 0.765 to 0.698 g/cm³, respectively, while bulk porosity increased from 41.8 to 43.3%. The highest static coefficient of friction was found on the plywood surface. The static coefficient of friction increased from 0.680 to 0.891, 0.605 to 0.741, and 0.530 to 0.644 for plywood, galvanized iron, and aluminum surfaces, respectively. The angle of repose increased linearly from 30.2 to 35.2° with the increase of moisture content.     

The resistance of packed beds of moth gram (Vigna aconitifolius) to airflow

The resistance of packed beds of clean moth gram (Vigna aconitifolius) to airflow was studied at moisture contents varying from 5.64 to 19.42% dry basis (d.b.) and at superficial air velocities ranging between 0.0104 and 0.8321 m s^?1 with bed depths of 0.2–0.6 m and bulk densities ranging from 745 to 875 kg m^?3. The airflow resistance of moth gram increased with increase in airflow rate and bulk density and decreased with moisture content. Results indicated that a 13.78% increase in moisture content decreased the pressure drop by 26.58% whereas, a 7.7% increase in bulk density increased the pressure drop by 43%. The modified Shedd's equation and Hukill and Ives equation were evaluated to see if they predicted pressure drop accurately. Airflow resistance was accurately described by the modified Shedd's equation. The statistical model that related airflow rate and bulk density could fit pressure drop data reasonably well. For loose fill beds an increase in grain moisture content increased the minimum fluidization velocity value from 1.1009 to 1.2391 m s^?1 whereas, for grain beds with 12.47% moisture content, the increase in bulk density decreased the minimum fluidization velocity value from 1.1152 to 1.0306 m s^?1.     

Geometric dimensions,density, and specific heat of chilli as a function of moisture content

Abstract

The geometric dimensions, weight of 1000 fruits, bulk density and specific heat of chilli (variety balijuri, Mymensingh local) were determined experimentally at the moisture contents of 5.14, 13.94, 26.47, 40.69, 58.94 and 73.03% (wet basis). Length of chilli fruit was found to be linearly dependent on moisture content. Chillies pose flat shape from the moisture contents 5.14 to 40.69% (wet basis) and in this moisture range the width and thickness were linearly dependent on moisture content. Above the moisture content of 40.69%, chilli fruit remained round in shape and fruit diameter was also increased linearly with the increase of moisture content. The weight of 1000 fruits, bulk density and specific heat appeared to be linearly dependent on moisture contents and these properties increased with the increase of moisture contents from 5.14 to 73.03% (wet basis).     

PHYSICAL PROPERTIES OF GRAM AS A FUNCTION OF MOISTURE CONTENT

This study was carried out to determine the effect of moisture content on some physical properties of gram. Six levels of moisture content ranging from 10.83 to 31.20 percent (dry basis) were considered for this study. Length, width, thickness, diameter of equivalent sphere, mass of 1000 grains and porosity increased linearly from 7.968 to 8.758 mm, 5.864 to 6.554 mm, 5.713 to 6.359 mm, 6.770 to 8.795 mm, 137.97 to 172.73 g, and 33.17 to 35.85% respectively with the increase of moisture content from 10.83 to 31.20%. The angle of repose increased from 27.03 to 33.27° with the increase of moisture content. Bulk density and true density decreased linearly from 787.31 kg/m³ to 712.61 kg/m³ and 1398 kg/m³ to 1250 kg/m³, respectively. Static coefficient of friction was determined over plywood, galvanized steel, celluloid sheet, and glass sheet. Static coefficient of friction varied from material to material and depended on the roughness and wetness of the true. The highest coefficient of static friction was found over plywood and lowest for glass sheet among the materials tested.     

Evaluation and Modeling of the Aerodynamic Characteristics of Watermelon Seed of Different Varieties

In this study, the aerodynamic properties of three varieties of watermelon seeds as a function of moisture content were evaluated and modeled. The watermelon seed varieties used were Charleston grey, Kaolack, and Sugar baby, and their moisture content ranged from 8.61 to 24.26, 10.30 to 26.11, and 7.78 to 23.23% wet basis (wb), respectively. The results showed that the terminal velocity of the Charleston grey, Kaolack, and Sugar baby varieties increased from 5.27 to 6.67, 4.40 to 6.23, and 4.00 to 6.60 ms^–1, respectively, as the moisture content increased. The Reynolds number of the three watermelon seed varieties increased with the increasing seed moisture content, while the drag coefficient generally decreased as the seed moisture content increased. Analysis of variance showed that the moisture content of the three watermelon seed varieties had significant effects on all the aerodynamics properties (p < 0.05). Mathematical models were developed to relate the moisture content of watermelon seeds with the values of the aerodynamic properties investigated.     

Thermal Properties of Kerstingiella geocarpa Seeds as Influenced by Moisture Content

The specific heat capacity, thermal conductivity and thermal diffusivity of Kerstingiella geocarpa seeds were determined as a function of moisture content. The initial moisture content of the seeds determined using the ASAE standard test was 10.0 % (d.b). The specific heat capacity of Kerstingiella geocarpa seed increased from 155.83 to 204.45 Jkg^?1k?1, as the moisture content increased from 10 to 30 % (d.b). The thermal conductivity of the seed increased from 5.13 × 10^?2 to 4.87 × 10^?1 Wm^?1k^?1, as the moisture content increased. The thermal diffusivity of the seed increased from 2.35 × 10^?4 to 3.66 × 10^?3 m²s^?1, as the moisture content increased. These values indicate the ability of the Kerstingiella geocarpa seed to retain heat when processed. The regression models that could be used to adequately express the relationships existing between the thermal properties of the Kerstingiella geocarpa seed and moisture content were established.     

DETERMINATION OF OIL POINT PRESSURE FOR MELON SEEDS

The oil point pressure of melon seed oil at different processing conditions, i.e., preheating moisture content (6.6, 8.3, 10.0 and 12.0% wet basis [w.b.]), heating temperature (70, 85, 100 and 115C) and heating time (15, 20, 25 and 30 min), was determined. The postheating moisture content increased with an increase in preheating moisture content and decrease in heating temperature and time. The oil point pressure obtained varied from 0.84 MPa for a moisture content of 6.6% (w.b.) heated for 30 min at 100C to 2.05 MPa for a moisture content of 12.0% (w.b.) heated for 15 min at 70C. The oil point pressure increased with increase in preheating moisture content and decreased as the heating temperature and time increased from 70 to 100C and from 15 to 25 min, respectively. A further increase in heating temperature to 115C and heating time to 30 min, however, increased the oil point.

PRACTICAL APPLICATIONS

Melon seeds are one of the commonly available oilseeds with a high oil content, and their high oil content makes them valuable for oil production. The optimization of the expression process through the identification of the oil point pressure of melon seeds is necessary for the effectiveness/efficiency of the process. The maximum oil point pressure (2.05 MPa) was obtained from the lowest value of heating temperature (70C) and time (15 min) and the highest moisture content (12.0% wet basis), while the minimum value (0.84 MPa) was from high heating temperatures and time and the lowest preheating moisture content. These indicate that reduced heat treatment of melon seeds increases the pressure required for expression, thus reducing process efficiency and increasing production cost.     

Moisture-Dependent Physical Properties of Kola Nut (Cola nitida) Seed

This study was carried out to determine the effect of moisture content on some physical properties of kola nut seed. Four moisture levels ranging from 47.48 to 61.4 % wet basis (w.b.) was considered. Results showed that there was linear increase in the mean length, width, thickness, geometric mean diameter, surface area, volume, sphericity, aspect ratio, 1,000 nut mass, bulk and true densities, and static coefficient of friction at different surfaces (mild steel and wood) by 3.58, 3.96, 6.29, 4.98, 10.72, 16.87, 1.54, 1.50, 26.23, 11.50, 7.27, and 17.86 to 23.53 %, respectively, with increase in moisture content from 47.48 to 61.4 % (w.b.). Furthermore, the angle of repose increased by 17.45 % while the porosity decreased by 3.85 % with increase in moisture content.     

Moisture-dependent physical properties of dried pomegranate arils

Physical properties of dried pomegranate arils and its variation with moisture content play an important role in designing of equipment for storage, conveying and handling. Physical properties of dried pomegranate arils in the moisture content range of 7–28 % (d.b.) were investigated. Size (GMD), sphericity, weight of the thousand dried arils, true density, bulk density, angle of repose and coefficient of friction at different surfaces (wood, galvanized iron and aluminum) increased, whereas porosity, hardness and toughness decreased with increase in the moisture content. All physical properties except porosity and angle of repose were significantly affected by the change in moisture content at probability level p ≤ 0.01.     

大豆堆压缩密度与体变模量研究

使用LHT-1型粮食回弹模量仪测定不同含水率不同围压的大豆堆的压缩密度与体变模量。测定结果表明:未受压缩的大豆堆密度随着含水率(8.58%~16.52%w.b.)的增大而减小(718~680 kg/m3),呈线性关系;不同含水率大豆堆的压缩密度随着围压(0~124 k Pa)的增大而增大,趋向各自的最大值,这些最大值随着含水率的增大而增大(774~914 kg/m3);大豆堆的体变模量随着围压的增大而增大,随着含水率的增大而减小。依据测定的数据,建立了以含水率与围压作为自变量压缩密度作为函数的预测模型,建立了以含水率与围压作为自变量体变模量作为函数的预测模型。模型预测的压缩密度、体变模量与实验测定值几乎一致(平均误差分别为5.2%和5.4%)。     

油茶籽鲜储过程中水分迁移与质构特性的变化

为明确油茶籽采后鲜储过程中水分迁移及质构变化情况,本实验以黔产油茶籽为实验原料,运用低场核磁共振(low field nuclear magnetic resonance,LF-NMR)、核磁共振成像(magnetic resonance imaging,MRI)技术探究鲜储过程中水分状态和分布规律,采用质地剖面分析(texture profile analysis,TPA)监测油茶籽鲜储过程中的质构特性变化,并进行相关性分析。结果表明:油茶籽在储藏期间水分含量不断下降,黔玉1号油茶籽水分含量由33.86%±3.03%(0 d)降至8.64%±0.24%(56 d),湘林210号油茶籽水分含量由53.03%±3.36%(0 d)降至10.73%±0.25%(56 d);种仁水分含量下降速率高于油茶籽;不易流动水在油茶籽中占比最高,储藏56 d时黔玉1号降至62.89%,湘林210号降至60.64%。新鲜油茶籽氢质子密度成像图光亮,随时间延长,局部水分流失较快,图像逐渐接近背景色。储藏期间,油茶籽破裂力、硬度不断下降,种仁破裂力、硬度曲折变化;种仁弹性逐渐丧失;黔玉1号种仁内聚性变化较小...     

Moisture-dependent engineering properties of sunflower seeds with different structural characteristics

The present study was carried out to investigate the effect of the moisture content of the seeds on engineering properties of sunflower hybrids with different structural characteristics. The properties were evaluated at seven levels of moisture from 2.0% to 20.1% (dry basis) for three selected sunflower hybrids. For both black-hull oilseed hybrid and confectionary hybrid, the variation in moisture content showed a statistically significant effect on dehulling ability, percentage of fines (broken grains with a diameter smaller than 2 mm) and all the physical properties studied (size, true density, bulk density, porosity, volume and weight, volumetric expansion coefficient, equivalent diameter and sphericity), except seed length in the confectionary hybrid and seed length and thickness in the black-hull oilseed hybrid. For the striped-hull oilseed hybrid, moisture content showed a significant effect only on dehulling ability, percentage of fines, seed width and thickness, bulk density and porosity. Of the oilseed hybrids, the striped hull genotype (higher hull content and both lower oil content and seed size) presented a higher dehulling ability. Nevertheless, the black hull hybrid resulted more sensitive to seed moisture changes. Although the confectionary hybrid showed a higher seed size, hull thickness and hull content, and lower oil content than the oilseed hybrids, the dehulling ability resulted fairly similar in the striped hull sunflower hybrids. The results suggest that sunflower seeds with different structural characteristics need to be conditioned with different moisture content before being subjected to the dehulling process.     

Potential of in-field and low temperature drying for reducing chlorophyll contents in canola (Brassica napus L)

The presence of green seeds in canola arises primarily from the common practice of swathing the crop prematurely in order to hasten the harvesting process and reduce the shattering losses. The purpose of this study was to determine the effects of plant maturity, swathing and duration of swathing on moisture and chlorophyll contents of canola seeds (Brassica napus L cv Westar), and to determine the effect of canola conditioning with air at 25·C and 90% RH on chlorophyll content. A standing crop of canola with 50% to 10% (w/w) seed moisture content was sampled at regular intervals in two consecutive harvest years (1989 and 1990). Canola was also swathed at three different stages of maturity, and seeds were checked for chlorophyll at 2-3 day intervals and compared with chlorophyll contents of seed from standing crop. Samples were conditioned in a thin layer with air at 25·C and 90% RH for 24 h, and chlorophyll was determined before and after conditioning. The chlorophyll of seeds decreased exponentially with a decrease in moisture content. Conditioning canola seeds decreased chlorophyll content by an average of 16% (SD = ± 12%).     

新收烤烟种子干燥处理方法初探

为提高新果收种子的活力,研究了蒴果和种子不同成熟度、不同种子袋以及干燥剂对种子活力的影响.结果表明,种子初始含水量随成熟度的提高而降低,种子的含水量随着干燥剂与种子比例的增加和成熟度的提高而降低,用棉布袋装的种子含水量低于尼龙袋(60目)装的种子,脱粒的种子含水量比带壳蒴果低.干燥处理的种子活力均高于对照.     

Radio Frequency Dielectric Properties of Bulk Canola Seeds under Different Temperatures,Moisture Contents,and Frequencies for Feasibility of Radio Frequency Disinfestation

The parallel capacitances and resistances of the bulk canola seeds were measured to determine the dielectric properties of canola seeds using a radio frequency dielectric fixture at different levels of temperature (30–80°C) and moisture content (5–11% w.b.), over the frequency range of 5 to 30 MHz. The dielectric constant (ε′) increased from 3.82 to 7.85 with increasing temperature and decreasing frequency regardless of the seed moisture contents. The dielectric loss factors (ε”) of the bulk seeds increased with increasing temperature and moisture content and decreased with frequency, ranging between 0.11 and 13.0. The penetration depth of the electromagnetic power in the bulk seeds varied from 1.30 to 48.0 m depending upon temperature, frequency, and moisture content. The distinct correlation of sensitivity of dielectric properties with moisture content was not observed except for that of penetration depth. The dielectric properties of the bulk canola seeds were higher than those of other oil seeds at various moisture contents; it might be affected by relatively higher linolenic acid content among other fatty acids. The large difference of the dielectric loss factors of insect pests cf. those of canola seeds showed potential for radio frequency disinfestation based on selective heating of insect pests in the canola seeds. The dielectric properties determined can be used for simulating temperature distribution within the bulk canola seeds during the radio frequency process.