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.     

Influence of storage conditions on the quality properties of wheat varieties

Effects on the quality properties in real storage conditions and galvanized steel silos for wheat varieties (cv. Bezostaya and Lancer) in the 180 day storage period were investigated. The wheat quality properties including grain moisture, crude protein, hectoliter weight, thousand grain weight, Zeleny sedimentation, wet gluten, dry gluten, and falling number were monitored in the laboratory in three replicates at regular intervals. From these results, crude protein, hectoliter weight, and thousand grain weight of Bezostaya and Lancer wheat varieties decreased with an increase in storage period. Grain moisture, Zeleny sedimentation, wet gluten, and dry gluten increased with storage period until the first two months and subsequently decreased. However, grain moisture for Lancer wheat increased until the third month of storage, after which it decreased. Falling number increased with increase in storage period.     

A comparison of the functional characteristics of wheat stored as grain with wheat stored in spike form

In this study, wheat grain and wheat spike with 12%, 14% and 16% moisture content were stored at 10, 20 and 30 °C for 0, 3, 6 and 9 months. After storage, wheat samples were investigated for hectolitre weight, gluten content, Zeleny sedimentation volume, enzyme activity, acidity, phytic acid and L colour value. Storage of wheat at different storage forms (spike and grain) and storage conditions showed considerable changes in grain quality. In general, the storage period of 3 months positively affected wheat quality. However, hectolitre weight, gluten, Zeleny sedimentation, enzyme activity, acidity and colour of wheat got worse at storage periods beyond 3 months. Hectolitre weight, wet and dry gluten, Zeleny sedimentation, phytic acid content and L Colour value of wheat stored in both spike and grain form significantly decreased during storage. However, the increase in grain moisture content, storage time and temperature resulted in significant increase in total titratable acidity and falling number values of wheat. Falling Number and phytic acid values of wheat stored in spike form were generally lower than wheat stored in grain form. Storage in spike form had a positive effect on especially wet gluten content of wheat stored at non-optimal storage conditions such as high grain moisture content and high temperature. Wet gluten of wheat stored in spike form was higher than that of wheat stored grain form after storage at 30 °C for 6 and 9 months. Wheat stored in spike form is more resistant than wheat stored in grain form against adverse storage conditions such as high moisture content and temperature and longer storage time.     

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.     

Aeration trial of farm-stored wheat for the control of insect infestation and quality loss

An aeration trial was conducted in collaboration with the Victorian Department of Agriculture, Australia, to study moisture content and quality changes in farm-stored wheat as a result of moisture uptake from the entering air. Two steel silos each filled with 44 tonnes of Olympic wheat at 33°C were aerated at the rate of 21/s per tonne with an average of 15 h of fan operation per week for 18 months. After 4 months of aeration, the average grain temperature at the centre of the bulk for each month ranged from 11–21°C depending on the season.The average moisture content of one bulk investigated in detail increased from 9.5 to 11.4% (w.b.) after 18 months of storage. Germination and some physical dough properties revealed some deterioration of the wheat near the duct. The rest of the bulk remained practically unaffected during storage and mainly free of storage fungi. Careful assessment of wheat quality before and after storage showed only small changes. The average insect fragment count at outloading was $\text{6}\text{100}\text{g}$ of flour which is considered to be a very low level.Germination and dough extensograph values were found to be, in this investigation, more sensitive indicators of deterioration than other quality tests.     

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.     

Evaluation of the effect of moisture content on cereal grains by digital image analysis

Physical appearance and kernel morphology significantly affect the grade of a harvested crop in addition to other factors such as test weight, percentage of foreign matter and constituent components. Moisture content of grain can potentially affect the physical appearance and kernel morphology. The objective of this study was to evaluate the effect of moisture content on the classification capability of colour, morphology and textural features of imaged grains. Colour images of individual kernels and bulk samples of three grain types, namely Canada Western Amber Durum (CWAD) wheat, Canada Western Red Spring (CWRS) wheat and barley were acquired using a machine vision system. The grain kernels were conditioned to 12%, 14%, 16%, 18% and 20% moisture contents before imaging. Previously developed algorithms were used to extract 123 colour, 56 textural features from bulk sample images and 123 colour, 56 textural, 51 morphological features from individual kernel images. The extracted features were analysed for the effect of moisture content. Statistical classifiers and a back propagation neural network model were used for classifying the grain bulk at different moisture contents. The colour and textural features of bulk grain images were affected by the moisture content more than that of the single kernel images.     

Physical Properties of Guar Seeds

A study on the guar seeds (Cyamopsis tetragonoloba) was performed to investigate the effect of moisture content on the selected physical properties. Moisture contents of seeds were varied from 5.2% to 25.0%, dry basis (d.b.). Seed geometric parameters, such as average length, width, thickness, geometric-mean diameter, surface area, volume, increased but sphericity decreased with increase in moisture content. The 1,000-seed mass increased linearly with moisture content. Bulk density of guar seeds decreased linearly when moisture content was raised from 5.2% to 25.0% d.b. On the other hand, true density decreased till moisture content was increased up to 20%. Further increase in seed moisture resulted in increased true density, which has not been observed in other food grains. The porosity decreased till seed 15.3% moisture and then increased with further addition of moisture. Angle of repose, coefficients of static friction on three different surfaces (plywood, mild steel, and galvanized iron), and terminal velocity increased linearly with seed moisture content.     

筒仓中小麦密度分布值的有限元分析

筒仓中粮堆密度分布值是预测筒仓中粮食对仓壁的压力、确定粮食通风阻力、计算筒仓中粮食质量的关键参数.使用有限元方法求解小麦堆的修正剑桥模型计算出筒仓中小麦堆的密度分布值.结果 表明,筒仓中小麦堆的密度随着粮层深度的增加而逐渐增大,但在筒仓拐角处密度随着粮层深度的增加而逐渐减小.在上部粮层,粮块密度随着粮块与筒仓中心轴距离...     

Safe storage guidelines for durum wheat

Storage conditions determine the safe storage period for any grain. Safe storage guidelines for durum wheat have not been developed, despite the fact that it is more susceptible to spoilage than other wheat classes. The rates of deterioration of durum wheat samples with 15, 16, 17, 18, 19 and 20% initial moisture content (wet basis) stored at 10, 20, 30 and 40 °C for 12 wk were studied. The grain deterioration parameters including seed germination, moisture content, appearance of visible mould, invisible microflora, free fatty acid value (FAV), and ochratoxin production were monitored at regular intervals. From these results, safe storage guidelines for durum wheat were developed with respect to the moisture content and storage temperature. Germination rates of the samples decreased with an increase in moisture content, temperature and storage period. Visible mould was found in all high moisture samples (17, 18, 19 and 20%) stored at high temperatures. FAV of the samples increased with moisture content and storage time.     

Effect of microwave heating of wheat grains on the browning of dough and quality of chapattis

Studies were conducted to evaluate the effect of microwave (900 W, 2450 MHz) heating of wheat grains conditioned to different moisture levels on the activity of polyphenol oxidase (PPO) and subsequent colour changes during storage of wheat dough. The results showed that microwave heating of wheat grains for 80 s decreased the PPO activity significantly ( P  ≤ 0.05) with an increase in moisture level from 12 to 18%. Whole wheat flour milled from microwave treated wheat grains (80 s, 18% MC) had 93.39% less activity of PPO. The dough balls (40 g), pressed and rolled into circular form (150.00 mm diameter and 2.00 mm thickness) and stored at 5–6 °C for 72 h. The colour of flattened circular dough was measured using Hunter Colour Meter and it was found that L -value (lightness) decreased from 64.21 to 60.23 in treated and from 64.79 to 47.93 in control samples after 72 h of storage. The results showed that the microwave heating effectively controlled the enzymatic browning in dough and improved the consumer acceptability of chapattis prepared from the same during refrigerated (5–6 °C) storage for 72 h.     

Relationships of rapeseed strength properties to seed size,colour and coat fibre composition

BACKGROUND: The size and strength of rapeseeds are factors likely to determine their suitability for storage and processing. The mechanical properties of whole seeds depend mainly on their coat composition. This study investigates variations in seed strength and colour between different‐sized rapeseeds. The paper also presents an explanation of the differences in seed mechanical properties through analyses of coat fibre composition. RESULTS: The strength properties of seeds were dependent on seed size and correlated with seed equivalent diameter. All measured strength indices showed that seeds of diameter above 2 mm were the most resistant. The mechanical properties of seeds were also correlated with the colour of seed surface, indicating that the most resistant seeds were those with values of H > 60°, S < 15% and I < 19% in the HSI colour space. The resistance of individual seeds was attributed to the surface density of soluble and insoluble dietary fibre, especially cellulose and lignin. CONCLUSION: The results suggest that the highest mechanical resistance shown by the largest and blackest rapeseeds can be associated with the high surface density of fibre components in the seed coat. Copyright © 2008 Society of Chemical Industry     

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.     

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.     

Quality changes in 12% moisture content canola stored in silo bags under Canadian Prairie conditions

A study was conducted for two storage years (2011–12 and 2013–14) to determine the changes in grain quality while storing 12% moisture content (m.c., wet basis) canola seeds in silo bags under Canadian Prairie conditions. Canola seeds were stored in three silo bags (67 tonnes per bag) and unloaded at three different times (one bag at a time) which represent 20 weeks of storage (unloaded in late winter), 28 weeks of storage (unloaded in spring) and 40 weeks of storage (unloaded after summer storage). Canola seed quality parameters (germination, free fatty acid value (FAV), and moisture content), and intergranular composition (CO₂ and O₂ levels) at different locations in silo bags were analysed every two weeks. Temperature of canola seeds at various locations in the silo bag was recorded every 30 min. The germination of canola seeds at most parts of the silo bags stayed above a safe level up to late winter (20 weeks of storage). At the top layer of the silo bags, germination of canola seeds decreased to below 30% during summer storage (after 40 weeks of storage). Moisture content of canola seeds increased at the top layer in both storage years. The FAV values remained at safe levels until 20 weeks of storage, and increased more than two times the initial values after summer storage. The commercial grades after first, second and third unloading (after 20, 28 and 40 weeks of storage) were Grade 1, Grade 2 and Feed Grade, respectively, in year 1. Whereas for year 2, these were Grade 1, Grade 1 and Grade 2 after first, second and third unloading, respectively. The grain quality analysis and commercial grading results indicated that ambient temperature had a major role in quality of canola during storage.     

Hot air-assisted radio frequency heating effects on wheat and corn seeds: Quality change and fungi inhibition

Hot air-assisted radio frequency (RF) heating has been proposed and studied as an alternative disinfestation method for grain seeds. In this study, hot air-assisted RF heating effects on fungi inhibition and its influence on physiological (seed vigor, germination rate) and biochemical (color, enzyme activity) qualities of wheat and corn seeds were further investigated. Results showed that high intensity hot air-assisted RF treatment (70 °C, 10 min) reduced seed vigor and germination rate for both wheat and corn seeds, but relatively mild intensity treatment (65 °C, 10 min) showed no significant influence on color and germination rate, and even enhanced enzyme activity (Superoxide dismutase-SOD, catalase-CAT and peroxidase-POD). Moreover, hot air-assisted RF treatment (65 °C, 10 min) reduced Aspergillus flavus by 2 and 3 log-scale (CUF/g) in wheat and corn seeds with the moisture content of 12.0%, and 3 and 4 log-scale for wheat and corn seeds when moisture content increased to 15.0%, respectively. These results indicated higher moisture content (a_w) of grain seeds would benefit fungi inhibition for hot air-assisted RF treatment, and with proper control of treatment conditions, hot air-assisted RF heating has the potential to inhibit fungi and maintain physiological and biochemical quality of grain seeds.     

Effect of temperature and fruit-moisture content on discolouration of dried, sulphured Bon Chretien pears during storage

Summary Discolouration of Bon Chretien pears which had been treated with sulphur dioxide and which had moisture contents of either 16, 18 or 20%, was monitored during storage at 4, 7, 10 and 20 °C. Colour was quantified in terms of CIE L*, a*, b*, hue and chroma. L* was used to predict quality retention. Discolouration was categorized as a decrease in all colour parameters, except a* which increased with storage. Measurement of L* showed that only fruit at 16% moisture content and stored at T ≤ 10 °C retained their original colour. The rate of change in overall colour was observed in the following order at 20 °C, 20% > 18 > 16% moisture content. Fruit with 18 and 20% moisture content could be stored at 10 °C for at least 140 weeks without changing their quality grading. Storage at 20 °C shortened this period to 60 and 27 weeks for fruit at 18 and 20% moisture content, respectively.     

Moisture-dependent properties of barnyard millet grain and kernel

The geometric mean diameter, sphericity, grain surface area, 1000 grain mass, true density (toluene displacement method), terminal velocity, dynamic angle of repose, coefficient of internal friction, coefficient of static friction at different surfaces (sun mica, canvas and mild steel surfaces), specific deformation and rupture energy of the grain were found to increase 12.21%, 4.79%, 30.47%, 30.75%, 6.74%, 32.99%, 127.05%, 60%, 18.57%, 34–67%, 69.2% and 88.87% respectively at increase of moisture content from 0.065 to 0.265 kg kg⁻¹ dry matter. However, true density (proximate composition method), bulk density, interstices and rupture force of grain was found to be decrease 8.64%, 20.1%, 86.49% and 21.17% respectively at increase of moisture content. Similar trend was observed for barnyard kernel also. True density (toluene displacement method) was found lower as compared to true density (proximate composition method) at all experimental moisture range indicated that the presence of void space inside the grain and kernel.     

Comparative utility of hermetic and conventional grain storage bags for smallholder farmers: a meta-analysis

Postharvest management is critical to attaining household food, nutrition, and income security. Hermetic grain storage bags offer an effective pesticide-free way to protect stored grain against fungal and insect infestation. We evaluated articles indexed in the Web of Science that included experiments comparing the storage efficacy of conventional and hermetic storage bags based on grain germination rate, insect infestation, physical damage, mycotoxin contamination, and changes in weight and moisture content. Compared with grain stored in hermetic bags, grain stored in conventional bags lost 3.6-fold more seed viability, contained 42-fold more insects, had 11-fold more physical damage, and lost 23-fold more grain weight, while grain moisture levels were similar for both hermetic and conventional storage bags. Mycotoxin contamination levels were not as frequently assessed. Levels could be low in grain stored in both types of bags, or levels could be low in hermetic bags and significantly higher in conventional bags. The improved properties of grain stored in hermetic bags can increase food security and household income by providing safe storage options for maintaining seed germinability, and for consumption and/or sale when food supplies are high, or when prices are low. Hermetic bags are economically feasible for use by subsistence farmers in Sub-Saharan Africa for grain for household consumption and for carrying-over seed for planting in the next season. Additional studies are needed to verify the mycotoxin contamination results and to determine if there are differences in functional food characteristics, e.g. flavor and cooking properties, that have not been as comprehensively studied. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

Microstructure and nutrient composition of hairless canary seed and its potential as a blending flour for food use

Canary seed is a true cereal with unique composition. The current study employed light and fluorescence microscopy to visualise starch, protein, phenolics and phytate in hairless canary seed (CDC Maria), a cultivar developed potentially for food use. Macronutrients, minerals and vitamins were evaluated in the developed cultivar and compared with a commercial hairy canary seed, cv. Keet. A control common wheat, cv. Katepwa, was grown adjacent to the canary seed varieties. The compositions of the two canary seed varieties were found to be similar with an average of 55.8 g/100 g of starch, 23.7% g/100 g of protein, 7.9% of crude fat, 7.3 g/100 g of total dietary fibre, 1.8 g/100 g of soluble sugar and 2.3 g/100 g of total ash in the whole grain. Regardless of the milling fraction (whole grain flour, white flour or bran), canary seed had more protein and crude fat and less starch, total dietary fibre and soluble sugar than had wheat. It also had higher concentrations of several minerals and vitamins than did wheat. The structure of the canary seed grain exhibited compound starch granules and protein bodies embedded in a protein matrix similar to that of the oat kernel. Baking tests showed that bread made with 100% hairless canary seed flour was significantly lower in loaf volume and crust and crumb colour than was wheat bread. However, bread with loaf volume, specific volume and crust colour comparable to those of the bread control was achieved by using up to 25% of hairless canary seed or 15% of roasted canary seed flour, thus demonstrating its potential for food applications.