Kernel Diameter Research Articles

Predicting Wheat Quality Characteristics and Functionality Using Near‐Infrared Spectroscopy

ABSTRACTThe accuracy of using near‐infrared spectroscopy (NIRS) for predicting 186 grain, milling, flour, dough, and breadmaking quality parameters of 100 hard red winter (HRW) and 98 hard red spring (HRS) wheat and flour samples was evaluated. NIRS shows the potential for predicting protein content, moisture content, and flour color b* values with accuracies suitable for process control (R2 > 0.97). Many other parameters were predicted with accuracies suitable for rough screening including test weight, average single kernel diameter and moisture content, SDS sedimentation volume, color a* values, total gluten content, mixograph, farinograph, and alveograph parameters, loaf volume, specific loaf volume, baking water absorption and mix time, gliadin and glutenin content, flour particle size, and the percentage of dark hard and vitreous kernels. Similar results were seen when analyzing data from either HRW or HRS wheat, and when predicting quality using spectra from either grain or flour. However, many attributes were correlated to protein content and this relationship influenced classification accuracies. When the influence of protein content was removed from the analyses, the only factors that could be predicted by NIRS with R2 > 0.70 were moisture content, test weight, flour color, free lipids, flour particle size, and the percentage of dark hard and vitreous kernels. Thus, NIRS can be used to predict many grain quality and functionality traits, but mainly because of the high correlations of these traits to protein content.

Silver precipitation: a new and easy to use method for measuring of wheat kernel surface area

Morphology, shape and surface area of wheat kernel are important factors for the characterisation of winter wheat (Triticum aestivum) varieties in the milling industry. The surface area of kernel, due to the lack of a simple and reliable method, is not measured, but usually calculated from the length and diameter of kernel. Silver precipitation, a new original method has been developed for the measurement of kernel surface area. This method is suitable for measuring the surface of cereal seed in case of individual kernel or more kernels together. According to the silver precipitation method, metal silver was precipitated on the kernel surface. After this step the precipitated silver was dissolved from the kernel and the silver concentration in the solution was measured by inductively coupled plasma optical emission spectrometry. The concentration of silver in the solution is in close correlation with the surface area of kernel. The method was calibrated to the direct surface measurement of individual kernels and was compared to the calculated surface results.

Stability analysis of kernel and milling characteristics in winter and facultative wheat

Consistency in quality of wheat grain and flour over seasons is critical to the manufacture of high quality products. The aim of this study was to measure the stability of kernel and milling quality characteristics. Thirteen hard red winter and facultative pure line and hybrid bread wheat varieties were evaluated at two planting dates for three seasons. IPC1 stability scores were compared with the AMMI stability values. Environment was found to be the most important contributor to variance in all traits. Genotype was a large contributor of variance for thousand kernel weight, kernel diameter and hardness index. GXE interaction contributed more to variation than genotype for test weight, percentage vitreous kernels, flour yield, flour colour and flour protein content at both planting dates. Molen was the most stable cultivar overall for the first planting date. At the second planting date PAN3235 and Limpopo were the most stable. The quality of the hybrids was the most inconsistent.

Contributions of Leaf Rust Resistance and Awns to Agronomic and Grain Quality Performance in Winter Wheat

Wheat (Triticum aestivum L.) cultivars grown in the Great Plains usually bear awned spikes for their putative value to grain yield and quality. Awnletted cultivars are generally limited to forage‐only systems. We hypothesized that an awnletted type would be more acceptable to grain producers if flag leaf senescence is delayed by protection against leaf rust (caused by Puccinia triticina Erikss.), the principal foliar disease affecting wheat production in the southern Great Plains. In field experiments under moderate levels of leaf rust infection, our objective was to estimate the effects of awns and leaf rust resistance according to the action and interaction of genes controlling these traits. Our analysis focused on agronomic and quality attributes previously shown to be influenced by these genes. Experimental lines were developed from crosses between leaf rust‐susceptible (awnletted or awned) near‐isolines of ‘Century’ and two leaf rust‐resistant, awned backcrossed‐derived lines with Lr41 or Lr42 from Triticum tauschii (Coss.) Schmal. For most attributes, genes controlling awns and rust resistance acted additively but with unequal effects. For the average effects of Lr41 and Lr42, grain yield increased by 63 and 26%, test weight increased by 5 and 3%, and kernel weight increased by 14 and 9%. Averaged across resistant and susceptible types for each gene, awns increased yield by 6.2 and 0%, increased test weight by 1.7% (either Lr gene source), and increased kernel weight by 6 and 4%. Rust resistance was more effective in compensating for the absence of awns than awns were in compensating for the lack of rust resistance. Leaf rust resistance improved milling quality by increasing flour yield and kernel diameter, independent of the presence or absence of awns. The development of awnletted cultivars with acceptable grain yield potential and quality appears achievable, but their utility in a grain‐only production system will be limited without leaf rust resistance.

Genetic Trends in Winter Wheat Grain Quality with Dual‐Purpose and Grain‐Only Management Systems

Hard winter wheat (Triticum aestivum L.) grain harvested from a dual-purpose (forage plus grain) crop is often perceived by users to have inferior end-use quality compared with that of a grain-only crop. In this paper, we determine if that perception has a scientific basis and if long-term genetic changes in grain quality are equally expressed under two management systems commonly practiced in the southern Great Plains. Uniform trials were established under grain-only and dual purpose management systems, each featuring whole-plot treatments of a foliar fungicide and split-plot treatments of 12 hard red winter (HRW) wheat cultivars spanning nearly 80 yr of genetic improvement. The study was conducted for 4 yr at the Wheat Pasture Research Center near Marshall, OK. Dual-purpose experiments were grazed from November through late February or early March of each year. Variables measured were kernel hardness, grain protein, flour yield, mixing time and tolerance, large-kernel fraction, kernel weight, and kernel diameter. The effect of fungicide treatment was not significant. Cultivar × system interactions were generally absent, and the correlation between management systems varied from r = 0.74 to 0.99 (P < 0.01), indicating a high level of consistency in quality between systems. Kernel weight in the dual-purpose system did not reach the same level as in the grain-only system for some cultivars, though kernel diameter was not negatively affected. Grain protein and dough strength, measured by mixing time and tolerance, were unaffected by management system. Significant genetic progress was observed in both systems for only the physical quality attributes (kernel weight and diameter, and percent large kernels). With exception of kernel weight, we detected no detrimental effect of the dual-purpose management system on cultivar performance, or on cultivar differences associated with breeding, for several characteristics commonly used to estimate bread wheat quality.

Relationship of Sorghum kernel size to physiochemical, milling, pasting, and cooking properties

Effects of kernel size on grain sorghum [ Sorghum bicolor (L.) Moench] quality were studied in an experiment designed to separate effects of kernel size from seedlot. The study utilized three sieve fractions of varying kernel diameter (>3.35, >2.80 and >2.36 mm) from six seedlots. Chemical composition, physical characteristics, milling characteristics, pasting properties, and cooking qualities were determined for each kernel size fraction. Large kernels lost less relative mass during 1 min of decortication, were higher in protein concentration, and lower in ash. Milling yields were higher from large kernels, and flour from large kernels had higher water absorbance, brighter white color, and larger particle size. Kernel size effects on Rapid Visco Analyzer (RVA) properties were not consistent. These results suggest that within the sorghum seedlots studied, an increase in kernel size is associated with an increase in sorghum quality as defined by the parameters measured in this study.

Conceptual Design of a Fluidized Bed Nuclear Reactor

A new type of nuclear reactor is presented that consists of a graphite-walled tube partly filled with TRISO-coated fuel particles. Helium is used as a coolant that flows from bottom to top through the tube, thereby fluidizing the particle bed. Only when the coolant flow is large enough does the reactor become critical because of the surrounding graphite that moderates and reflects the neutrons.The fuel particle designed for this reactor is strongly undermoderated and has a temperature coefficient of reactivity that is sufficiently negative. The outer diameter is 1 mm with a fuel kernel diameter of 0.26 mm. The fuel enrichment (16.7%) and the core inventory (120 kg of uranium) inherently limit the maximum power to 16 MW(thermal).A lumped-temperature point-kinetics model has been made that describes the fluidization of the particle bed, coupled to the thermal hydraulics and the neutronics of the core. The model has been linearized around the stationary solution, and the transfer function from coolant mass flow rate perturbations to reactor power fluctuations has been calculated. From a root-locus analysis, the reactor operation is shown to be stable with respect to small variations of the coolant mass flow rate around the stationary operation points.Transient analyses with the nonlinear reactor model show that for the three transients considered (a step in the coolant mass flow rate, a decrease of the coolant inlet temperature, and a loss of heat sink), the fuel temperature remains well below 1600°C. Recommendations are made for further research.

Requirements for high temperature reactor fuel particle design assessment

In the framework of a large Research and Development programme devoted to High Temperature Reactors (HTR) and set up in the CEA from 2000 on, we will address ourselves to the issue of coated fuel performance and design. Although HTR fuel main features have been established for a long time, we need today to reassess the fuel design to make sure that it meets the requirements linked to the most recent projects of High Temperature Reactors. Thus, in collaboration with Framatome and in connection with the Gas Turbine - Modular Helium Reactor (GT-MHR) international project, we are planning to perform parametric thermal and mechanical studies, regarding different particle design options (kernel diameter, layers composition and thickness) and seeking optima concerning particle leak tightness and fission product retention. But to initiate such studies, we have first of all to define the design bases and the requirements for HTR fuel, in terms of kernel composition (fissile element, oxide stoechiometry, enrichment), particle and compact geometry (dimensions, particle volume fraction in the graphite matrix), power density, cooling gas temperature and irradiation conditions (burnup, fast fluence).

Deconvolution of several versions of a scene perturbed by different defocus blurs: influence of kernel diameters on restoration quality and on robustness to kernel estimation

It has been shown many times that using different versions of a scene perturbed with different blurs improved the quality of a restored image compared with using a single blurred image. We focus on large defocus blurs, and we first consider a case in which two different blurring kernels are used. We analyze with numerical simulations the influence of the relative diameter of both kernels on the quality of restoration. We then quantitatively evaluate how the two-kernel approach improves the robustness of restoration to a difference between the kernels used in designing the algorithm and the actual kernels that have perturbed the image. We finally show that using three different kernels may not improve the restoration performance compared with the two-kernel approach but still improves the robustness to kernel estimation.

Some Calculations of the Failure Statistics of Coated Fuel Particles

The fact that not all coated fuel particles in a batch fail after the same irradiation history is due to manufacturing variations in values of individual particle parameters. Two methods of calculating the failure fraction as a function of burnup in terms of these statistical variations are discussed: (a) a random sampling of particles combined with a simple stress model, and (b) the convolution of the individual variations combined with an advanced stress model.These methods were applied to particles manufactured by two laboratories in support of the U.K. low-enriched fuel cycle high-temperature reactor design. Experimental values of variations in the following parameters were included: kernel diameter and porosity, thickness of buffer, seal, silicon carbide and inner and outer pyrocarbon layers (all assumed to be normally distributed), and the silicon carbide fracture stress (assumed to obey a Weibull distribution). It was concluded that the convolution approach was the more satisfactory method.The results enable one to identify which of the various parameters considered are the most worthwhile for manufacturers to put development effort into so as to reduce their variability. For the particles considered here, these are primarily silicon carbide fracture stress, followed by kernel porosity.

Abbrandbedingtes schwellen hochdichter oxidischer htr-brennstoffkerne

BISO- or TRISO-coated high-density UO 2 kernels with varying degrees of enrichment and with mean kernel diameters between 220 and 820 μm have been irradiated at 900–1300°C to burn-ups between 0.5 and 52.5% fima. From microradiographic measurements, burn-up-induced increases in kernel diameters were deduced: these ranged up to 12.8% (corresponding to 43.5% volume increase). In the low burn-up region, kernel diameters increase approximately linearly with burn-up. This increase is more pronounced for small kernels than for larger ones, it is higher for TRISO-coated kernels than for BISO-coated ones. In the high burn-up region, the dimensional increase seems to become independent of burn-up. (U, Th)O 2 kernels show more swelling than pure UO 2 kernels with identical diameters. All these results can be explained, at least qualitatively, taking into account results from fission-gas release measurements.

Moisture Contraction of Spanish Peanuts1

Abstract The linear coefficient of moisture contraction for skinned Spanish peanut kernels was determined at 40°C and at 20, 42, 70, and 80% drying air relative humidities. Kernel lengths and diameters were measured optically with a microprojector. Cubical coefficients of moisture contraction were calculated from the linear-coefficients by approximating peanut volume by a prolate spheroid shape. Cubical coefficients ranged from 5.5 to 7.71 × 10-3 cm3/cm3 % MC and generally increased as drying air relative humidities increased.

Techniques for Quality Inspection of Coated Fuel Particles

Various techniques have been developed for the quality inspection of coated fuel particles. The present report summarizes these techniques, which include random sampling of particles by two-stage sampling, measurement of kernel diameter and coating thickness by metallography and X-ray microradiography, determination of density by Hg displacement, m-xylene pycnometry and sink-float technique, determination of the crystallite orientation of pyrolytic carbon, assessment of uranium contamination by α-counting, fluorescence analysis and fission track counting, determination of the C/Si ratio of SiC layer by chlorination, and measurement of the crushing strength of particles. Quality evaluation based on statistical treatment of the data is also described briefly.

Techniques for Quality Inspection of Coated Fuel Particles

Various techniques have been developed for the quality inspection of coated fuel particles. The present report summarizes these techniques, which include random sampling of particles by two-stage sampling, measurement of kernel diameter and coating thickness by metallography and X-ray microradiography, determination of density by Hg displacement, m-xylene pycnometry and sink-float technique, determination of the crystallite orientation of pyrolytic carbon, assessment of uranium contamination by α-counting, fluorescence analysis and fission track counting, determination of the C/Si ratio of SiC layer by chlorination, and measurement of the crushing strength of particles. Quality evaluation based on statistical treatment of the data is also described briefly.

Effects of Temperature in the Ripening Periods upon the Development and Qualities of Lowland Rice Kernels

Lowland rice plants (Norin-17) of early and sermi-late cultivations, and the ears of the same variety of late cultivation were treated during night time with high (30°C) and low (20°C) temperature (15°C -30°C for the ear treatment) for certain periods in various stages of kernel development. Investigations on maturation, fruiting and specific gravities of the seeds, and some microscopic observations on bran layer and starchy tissue of the kernels were conducted. The results are summmarized as follows: 1) High night temp. accelerated the kernel development and maturation. 2) Chalky kernels and partially-chalky kernels markedly occured in the plots of high night temp. around 1O days after flowering. That was presumably due to an unbalance in supply and demand of nutrients, and to increased consumption of storage foods in the weak kernels, which were caused by high temp. 3) Both high and low night temp. 5 to 15 days after flowering caused milky-white kernels which considered to be due to the temporary hindrance of ripening. Many of milky-white kernels due to hindrance in early ripening stages had an opaque part (white-core-like but different from that of white-core kernel in shape and location) in their tissues. 4) Measurements on specific gravities of paddy, brown rice and parts of kernel revealed insufficiency of storage matter accumulation in the outer parts of kernel under high night temp. conditions. But as for the inner parts, they had larger s.g. values than those from low temp. plots, indicating good accumulation in these parts in earlier stages of seed development. 5) High night temp. in early stages of seed growth increased aleurone cells and thickness of bran layer on back side of kernel. Low temp. decreased these measurements. 6) On the cross sections of kernels from high night temp. plots a well-ar-ranged radial starch tissue (characteristic of Koshitsu-Mai) was observed. 0n the other hand, remarkable development of flatish cells along the dorso-ventral diameter of kernel (typical for Nanshitsu-Mai) was noticed in the kernels from low night temp. plots