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1.
Market value of oat grain is largely determined by test weight or bulk density, yet little is known of the physical basis for test weight in oats. We have hypothesized that a larger sized groat relative to the oat grain (the kernel with the hull) would generate higher test weight oats because the groat is the densest structure in the oat grain. We tested this by measuring oat grain size and oat groat size by digital image analysis for 10 genotypes grown in 10 environments. We also measured other physical characteristics of the oats grains and groats including mean grain and groat mass, test weight, and groat percentage. We found that the groat/ grain size ratio was highly correlated with test weight. Because the oat grain image area was nearly twice that of the groat, we suggest that there are significant amounts of empty space within the oat hull, which detracts from test weight. We also found that oat groat size distributions, like oat grains, fit bimodal distributions better than normal distributions.  相似文献   

2.
Test weight or bulk density of oats (Avena sativa L.) has a major influence on the monetary value of oat grain. We hypothesize that test weight can be attributed to grain density and packing efficiency. We have measured oat grain volume and density by a sand‐displacement method and derived the packing factor for six oat cultivars grown in three environments. Volumes of individual grains were 31–38 mm3 and were highly correlated with grain mass. Grain densities were 0.96–1.03 g/cm3. Packing efficiency, defined as the space proportion occupied by the grains, was 53–55%. Regression analysis suggested that 78% of the variation in test weight could be attributed to grain density. Size fractionation of grain by sieving and analysis by digital image analysis indicated that smaller grains within an oat sample packed more efficiently than larger grains and larger grains in a sample were less dense than the smaller grains. Analysis of oat grain components indicated groat densities were ≈1.29 g/cm3 and hull densities were ≈0.69 g/cm3. The difference in densities between groat and hull provide a physical basis for the recognized relationship between groat percentage and test weight.  相似文献   

3.
Commercial processing of oats for human consumption generally requires impact dehulling to isolate groats from the hull. Impact dehulling involves feeding oat grain into the center of a spinning rotor that expels the grain against the walls of the dehuller. The force of the impact breaks the hull from the groat. We have tested the effect of rotor speed on dehulling efficiency, groat breakage, and unbroken groat yield on 18 oat genotypes from replicated plots in six different environments. Dehulling efficiency and groat breakage increased with rotor speed with all genotypes and environments, but there were significant genotypic and environmental effects as well. In general, genotypes with higher test weight and kernel density dehulled more efficiently at slower rotor speeds. Oat genotypes with higher oil and protein concentrations in their groats tended to break less during dehulling. Oats from hotter, drier environments suffered greater groat breakage. Maximal unbroken groat yield represented a balance between dehulling efficiency and groat breakage, but groat proportion and dehulling efficiency appeared to be the most important factors contributing to groat yield.  相似文献   

4.
The cholesterol-lowering effect of cereal grains has been associated with the soluble fiber component of dietary fiber. β-Glucan is the major soluble fiber component of barley (Hordeum vulgare L.) and oat (Avena sativa L.). Much research has been conducted to determine the β-glucan content of barley and oat genotypes from many different countries. However, genotypes of both crops always were grown in separate experiments, making direct comparisons between the two crops difficult. This study compares in the same experiment the β-glucan content of nine barley and 10 oat genotypes grown at two locations in each of two years (i.e., four environments) in North Dakota. Averaged across genotypes, total β-glucan content of barley and oat groat was similar. Soluble β-glucan content of oat groat was greater than barley, and oat groat had a greater ratio of soluble-to-total β-glucan than barley. The soluble β-glucan content and ratio of soluble to total β-glucan content of the “best” barley genotypes were less than that of oat genotypes with the highest levels of these two traits.  相似文献   

5.
Central to commercial oat (Avena sativa L.) processing is impact dehulling. During impact dehulling, oats are fed into a spinning rotor that expels the grains against an impact ring. The impact frees the groat from the hulls. To optimize dehulling protocols, we examined the effects of physical grain characteristics and rotor speed on oat dehulling using an impact dehuller. We separated grain of three cultivars (Gem, CDC Dancer, Ronald) according to size by sieve fractionation (separation by width), disk fractionation (separation by length), and by gravity table (separation by density). Grains were characterized by mass, digital image analysis, and bulk density. Samples (50 g) were adjusted to 9% moisture and dehulled at four different rotor speeds. Groat percentage, dehulling efficiency, and groat breakage were measured after dehulling. In general, oats with higher bulk density dehulled more efficiently at slower rotor speeds, regardless of grain mass. Groat breakage increased with rotor speed and with grain mass. Adjusting dehulling conditions according to grain size improved groat yields over optimal dehulling conditions for unfractionated grains for some cultivars. More refined fractionation of grain according to bulk density may provide further improvement of groat yield during impact dehulling.  相似文献   

6.
Correlations among grain sorghum quality factors (proximate composition, physical properties, and water absorption properties) were evaluated. Samples of 46 commercial hybrids (24 and 22 from crop years 1993 and 1994) were analyzed for starch, protein, crude free fat, test weight, absolute density, 1,000 kernel weight, percent kernel abraded, water absorption index, initial water absorption rate, and moisture saturation point. Test weight, absolute density, and percent kernel abraded were positively correlated among themselves (r > 0.5). Protein was negatively correlated with both test weight and absolute density (r < -0.5), while moisture saturation point showed negative correlations with test weight, absolute density, 1,000 kernel weight, and percent kernel abraded (r < -0.4). Principal component factor analysis through the covariance matrix explained 95% of the total variation of quality factors among hybrids (two factors), and, through the correlation matrix, 85% of the total variation (five factors). Water absorption rate decreased with increasing starch content of grain sorghum kernels as water absorption rate increased and amount of water for saturation decreased with softening of kernels.  相似文献   

7.
Oat kernel size uniformity is important to the oat milling industry because of the size fractionations that occur in the milling process. We measured frequency of single, double, and triple kernel spikelets and kernel mass of primary, secondary, and tertiary kernels from each spikelet type (for a total of six kernel types) to determine relative influence of kernel type, panicle position, genotype, and environment on oat kernel size for 10 oat cultivars grown at four locations. Kernel type was the most important factor affecting kernel size. Primary kernels from triple kernel spikelets were larger than primary kernels from double kernel spikelets. Tertiary kernels were the smallest. Environments that produced larger kernels also produced higher frequencies of triple kernel spikelets. Some genotypes produced no triple kernel spikelets in any environment, whereas others produced varying proportions, depending on the environment. Kernels closer to the top of the panicle were larger than those near the base. The presence of tertiary kernels was neither associated with lower groat percentages nor with increased proportions of undersized kernels. Most undersized kernels were kernel types other than tertiary.  相似文献   

8.
The aim of this study was to improve the bioavailability of the dietary phenolic acids in flours from whole grain barley and oat groat following fermentation with lactic acid bacteria (LAB) exhibiting high feruloyl esterase activity (FAE). The highest increase of free phenolic acids was observed after fermentation with three probiotic strains, Lactobacillus johnsonii LA1, Lactobacillus reuteri SD2112, and Lactobacillus acidophilus LA-5, with maximum increases from 2.55 to 69.91 μg g(-1) DM and from 4.13 to 109.42 μg g(-1) DM in whole grain barley and oat groat, respectively. Interestingly, higher amounts of bound phenolic acids were detected after both water treatment and LAB fermentation in whole grain barley, indicating higher bioaccessibility, whereas some decrease was detected in oat groat. To conclude, cereal fermentation with specific probiotic strains can lead to significant increase of free phenolic acids, thereby improving their bioavailability.  相似文献   

9.
Eight Scandinavian oat cultivars were studied as grains, groats before and after kiln drying, rolled oats, and oatmeal for 62 physical, chemical, and sensory parameters over three consecutive crop years. The objectives were to study cultivar and year differences, and the relationships between parameters to find out the cultivars most suitable for rolled oats production and to understand how grain parameters are reflected on groat, rolled oat, and oatmeal characteristics. The cultivars and crop years differed (P < 0.05) in most of the parameters. In addition, many groat, rolled oats, and oatmeal variables showed a significant year by crop interaction. Several grain variables were significantly interrelated but only two, moisture and amount of dark and damaged grains, had a strong correlation (r > 0.70) to rolled oat parameters, the former correlating negatively to crude fat and the latter positively with maximum viscosity value. However, some weaker (r < 0.70) negative associations were found such as those between kernel size value and β‐glucan content and water binding capacity of rolled oats. In general, the variables analyzed at different processing stages correlated strongly, indicating good retention of groat properties during processing. Various associations were found between the physicochemical parameters of rolled oats and sensory properties of oatmeal. In principal component analysis, factor 1 mostly represented rolled oat parameters such as crude fat, color values L and a, and oatmeal parameters such as toasted aromatics, coarseness, and size of swollen particles. Factor 2 represented properties that pertain to structure and water and rolled oats interactions. The cultivars were also grouped according to these properties. The results suggest that the rolled oat process deserves optimization on a cultivar basis, particularly when specific product properties such as good water binding capacity are required.  相似文献   

10.
Nutritional composition of oat kernels from 18 genotypes grown in six environments in North Dakota, U.S.A., was analyzed by chemical means. Of the macronutrients, mean starch concentration was 56.5%, protein was 18.1%, oil was 7.9%, neutral detergent fiber (insoluble fiber) was 6.0%, β‐glucan (soluble fiber) was 5.2%, ash was 1.9%, and soluble carbohydrate was 0.6%. These add up to 96.2%, which appears to account for most of the mass of the oat kernel. Protein amino acid analysis indicated 4.5% lysine and 1.8% methionine. Free amino acid analysis indicated 1,129 μg of asparagine per gram of flour. The 18:1 and 18:2 fatty acids were the most abundant in oat lipids. Mean micronutrient concentrations in oat kernels included potassium (3,419 ppm), magnesium (1,416 ppm), calcium (441 ppm), iron (52 ppm), zinc (26 ppm), and selenium (0.38 ppm). Analysis of variance indicated significant genotypic and environmental variation, as well as significant genotype × environmental interaction for most of the nutritional components. In general, protein was higher in drier, hotter environments, whereas oil, β‐glucan, and starch were higher in wetter, cooler environments. The results provide a unique database of a collection of compositional components for specific oat genotypes in diverse environments.  相似文献   

11.
Avenanthramides (avn) are antioxidant compounds found in oat tissues, including the grain, that are of interest from a nutritional standpoint. In this study, we have measured avenanthramide concentration in the grain of 18 oat genotypes grown in six environments. These genotypes varied widely in crown rust (Puccinia coronata) resistance. Crown rust infected two of the six environments studied. The grain avenanthramide concentrations in the crown rust environments were significantly higher than those in the uninfected environments. Avenanthramide concentrations in the crown rust infected environments was also significantly correlated with their genetic crown rust resistance, as evaluated in the field. These results suggest that avenanthramide accumulation in the grain is associated with crown rust infection and that, in most of the cultivars evaluated, the extent of their accumulation also correlated with their genetic disease resistance; avenanthramide accumulation in the grain was, with noted exceptions, highest in those cultivars showing the greatest genetic resistant to crown rust.  相似文献   

12.
Five Canadian oat genotypes were grown at six environments in Manitoba to assess the effects of genotype, environment, and genotype‐by‐environment interaction on oat starch properties and end‐product quality. Genotypic variation was significant for total starch, amylose content, starch swelling volume (SSV), Rapid Visco Analyser (RVA) pasting viscosities, differential scanning calorimetry (DSC) thermal properties, and starch gel texture as well as the quality of flakes and cooked oatmeal made by laboratory‐scale methodologies. Environment was the dominant factor contributing to the total variation of starch content, RVA pasting viscosities, SSV, and DSC thermal properties. Most measurements of starch gel and oatmeal texture were not affected by growing environment. Cross‐over analysis revealed that changes in the ranking of genotypes across environments occurred for starch RVA hot paste, breakdown and shear thinning viscosities, work of gel compression, flake hydration capacity, and the proportion of large flakes, indicating that breeding for these traits would require multiple testing sites. Trends were observed between oatmeal texture and several flake and starch gel properties, warranting further study. Results of this study indicated that there is a potential to breed Canadian oat cultivars with improved functional end‐product quality for use in the milling and food manufacturing industries.  相似文献   

13.
The production of oat bran involves the dehulling of oats, inactivation of their enzymes, and the subsequent grinding and sieving of the clean groats to isolate the larger bran particles. The bran yield from the oat groats may be related to their hardness, as it is in wheat. Groat breakage, which occurs during the dehulling process, reduces milling yield and may also be related to groat hardness. This study sought to investigate genotypic and environmental effects on oat dry milling and oat dehulling characteristics, and attempted to define properties associated with oat groat hardness. Significant genotypic differences in bran yield were largely attributed to groat composition, where higher β‐glucan and oil concentrations in the groat were associated with higher bran yields. Bran composition was largely dependent on a combination of the bran yield and the groat composition. Although groat breakage was correlated with bran yield and with groat β‐glucan concentration, environmental factors appeared to be more influential. Locations that had suffered severe crown rust infestations exhibited higher rates of groat breakage during dehulling. Bran yield was not as strongly affected at the locations infested with crown rust, indicating that bran yield and groat breakage are manifestations of different types of groat hardness and are only partially related.  相似文献   

14.
The development of high‐quality wheat (Triticum aestivum L.) cultivars depends on a thorough understanding of the constituents of grain and their variation due to genetics and environment. Arabinoxylans (pentosans) are key constituents of wheat grain and have broad and far‐reaching influences on milling and baking quality. However, variation in arabinoxylans due to genotype and environment are not fully understood. In this study, 25 hard winter and 25 hard spring wheat commercial cultivars and advanced breeding lines developed from eight public and private breeding programs in the U.S. Pacific Northwest were analyzed for water‐extractable and total arabinoxylan contents (WE‐AX and total AX), and the proportion of total AX that was water‐extractable. Winter and spring genotypes were grown in three environments each. The results indicated that there were significant differences among both sets of hard wheat genotypes for WE‐AX, total AX, and proportion of total AX that was WE‐AX. The WE‐AX and total AX mean content ranges for the winter cultivars were 0.390–0.808 and 3.09–4.04%, respectively; and for the spring cultivars 0.476–0.919 and 3.94–4.70%, respectively. WE‐AX as a percentage of total AX was similar between the two genotype sets, 11.7–23.0%. Arabinoxylan fractions were generally not correlated with grain protein, test weight, and kernel hardness. The two highest correlations for winter wheats were between protein and total AX (r = –0.40) and test weight and percentage of total AX that were water‐extractable (r = 0.37) for winter wheats. Among spring wheats, single‐kernel characterization system hardness was negatively correlated with WE‐AX and proportion of total AX that was WE‐AX (r = –0.46 and –0.51, respectively). Although often significant, arabinoxylan fractions were usually not highly intercorrelated, indicating some independence of traits. Notable genotypes, being especially high or low for one or more arabinoxylan fraction and, thus, candidates for further genetic study and cross‐breeding, included Juniper, Eddy, and ORN980995 winter wheats, and Hollis, Alta Blanca, and WQL9HDALP spring wheats. Although the results indicate that arabinoxylan fractions of wheat grain can be highly influenced by environment, there is clear support for the existence of genetic differences, especially for WE‐AX and the proportion of total AX that is water‐extractable. As such, the manipulation of arabinoxylan content of wheat grain seems to be a reasonable breeding objective.  相似文献   

15.
Shriveled kernels lower wheat test weight and reduce milling flour yields. Test weight is also lowered by rain-dry cycles that cause kernels to puff (exhibit, in part, loosened layers of pericarp). A numeric score was developed for degree of puffing and for degree of shriveling based on simple measurement devices. Wheat samples were evaluated for test weight and Single Kernel Characterization System (SKCS) hardness index, SKCS kernel weight, milling flour yield, and kernel density (hexane displacement). Those evaluations were performed before and after samples were air-aspirated to remove all shriveled kernels. Test weight, SKCS hardness index, and density of aspirated samples were used to develop a puffing score. Changes (resulting from aspiration) in test weight, SKCS kernel weight, and flour yield were used to develop a shriveling score. Higher puffing scores were related to elevated α-amylase activity. Puffed kernels were softer and were not associated with decreased flour yield. Puffing and shriveling scores were independent (poorly correlated), but together predicted 95% of the variation in original, nonaspirated test weight.  相似文献   

16.
Sprout damage of oats can occur when mature grain is left in the field after maturity and rainfall induces the germination process in the seeds. Although characteristics of sprout damage have been described thoroughly in many grains including wheat, rye, triticale, and barley, such characteristics have not been identified in oats. During a field study of oat quality, one site exhibited much higher rates of groat breakage during dehulling than other sites. Determination of falling number values on groat flour and a visual inspection of the grain suggested that the higher rates of groat breakage were associated with sprout damage. This hypothesis was confirmed with artificially sprouted oats, where sprouted grain exhibited lower falling numbers and lower stirring number values, suggesting increased α‐amylase activity in the sprouted oats. Sprouted oats exhibited much more breakage during dehulling, decreased β‐glucan concentration, and decreased β‐glucan integrity, as evaluated from the viscosity of steamed groat flour slurries. We suggest that the increased breakage was a result of the weakening of cell walls, as evidenced by the loss of β‐glucan concentration and integrity.  相似文献   

17.
Wheat (Triticum aestivum L.) genotypes with short mixing times usually have low mixing tolerance values, which make them more sensitive to overmixing in commercial bread production. In this study, we evaluated the genotypic and environmental effects on agronomic performance and end‐use quality of 27 experimental genotypes (hereafter referred to as mixing tolerant genotypes) which were identified in an initial screen as having short mixing times and good mixing tolerances to 1) determine whether genotypes identified in a preliminary end‐use quality screen as lines with usually long tolerances but short mixing times were due to their genotype (G), the environment (E), or G × E; and as these results were unusual, 2) determine whether or not our initial screen predicts end‐use quality, and 3) determine the stability of both agronomic and end‐use quality traits. The 27 genotypes and five check cultivars were grown in a randomized complete block design with two replicates in nine environments in 1997 and 1998. All plots were harvested for grain yield. The harvested grain from the first replicate and random genotypes from the second replicate were micromilled to produce flour samples for evaluation of flour yield, protein content, and mixograph mixing time and mixing tolerance values. Seed diameter, thousand kernel weight, and kernel hardness were also measured in three environments. Environment, G, and G × E interaction effects (mainly changes in magnitude) were significant for most agronomic and end‐use quality parameters. Our initial screen, which had identified 27 genotypes, was partially effective in identifying genotypes that have shorter mixing time values compared with their mixing tolerance values. We identified four genotypes (15%) from the mixing tolerant genotypes that had a good mixing tolerance value and relatively shorter mixing time, as did the released cultivars ‘Agate’ and ‘Scout 66’. However, mixing characteristics values of all genotypes fell within the acceptable limits, indicating our screen effectively identified genotypes with acceptable quality. Mixing tolerant genotypes, which had been identified as having short mixing time scores and long mixing tolerance scores, were considered stable across environments.  相似文献   

18.
Twelve hard red winter wheat cultivars were grown at four locations in central Kansas to evaluate the role of foliar fungal diseases on wheat end-use quality in 1995. Disease was allowed to develop naturally on control plots and was controlled partially on plots treated with a systemic fungicide. After harvest, wheat samples were evaluated for the impact of the disease complex (leaf rust, tan spot, speckled leaf blotch) on physical grain quality, grain protein, milling properties, flour absorption, and peak mixing time. Data were analyzed using a mixed model to account for random (location and block) and fixed (cultivar and fungicide) effects. Location significantly influenced quality characteristics except kernel size and peak mixing time. The magnitudes of variation among random effects on all quality characteristics were larger for location than for the interactions between location × cultivar and location × fungicide. The fixed effects portion of the analysis revealed that the cultivar × fungicide treatment interaction significantly affected test weight, kernel protein, and flour absorption. Fungicide treatment resulted in significant increases in yield and kernel weight. Cultivar significantly affected all quality characteristics except kernel size and peak mixing time. Disease resistance exerted a significant influence on yield and test weight. The economic benefit associated with improved wheat quality from fungicide treatment was variety specific. Three cultivars (TAM 107, Karl 92, and Ike), which account for 50% of the 1997 planted wheat acres in Kansas, demonstrated positive improvements in test weight and protein in response to fungicide treatment.  相似文献   

19.
A comprehensive analysis of the variation in wheat grain ash content has not been previously conducted. This study assessed the relative contribution of genotype and environment to variation in ash content, with a particular aim of ascertaining the potential for manipulating the trait using contemporary adapted germplasm. A total of 2,240 samples were drawn from four years of multilocation field plots grown in the wheat production areas of Oregon and Washington states. Genotypes included commercial cultivars and advanced breeding lines of soft and hard winter, and soft and hard spring wheats with red and white kernel color, several soft white club wheats, and one soft white spring waxy wheat cultivar. In addition to ash, protein content, test weight, and Single Kernel Characterization System kernel hardness, weight and size were also measured. In total, 20 separate fully balanced ANOVA results were conducted. Whole model R2 values were highly significant, 0.62–0.91. Nineteen of the 20 ANOVA results indicated significant genotype effects, but the effects were not large. In contrast, environment effects were always highly significant with F values often one to two orders of magnitude larger than the genotype F values. The grand mean for all samples was 1.368% ash. For individual data sets, genotype means across environments varied ≈0.1–0.3% ash. The genotypes judged noteworthy because they had the highest least squares mean ash content were OR9900553 and ClearFirst soft white winter, NuHills hard red winter, Waxy‐Pen and Cataldo soft white spring, and WA8010 and Lochsa hard spring wheats. Genotypes with lowest least squares mean ash were Edwin (club) soft white winter, OR2040073H hard red winter, WA7952 soft white spring, and WA8038 hard spring wheats. In conclusion, wheat grain ash is more greatly influenced by crop year and location than by genotype. However, sufficient genotype variation is present to plausibly manipulate this grain trait through traditional plant breeding.  相似文献   

20.
Test weight or bulk density in durum wheat is a physical quality characteristic considered by semolina millers. High test weight values are desirable because they positively influence market grade and price. This study reports data on kernel size features, determined on a sample size of only 25 kernels, replicated three-times, of 16 commercial durum wheat cultivars grown in two locations in southern Italy, to ascertain whether some kernel traits could be related to test weight. For each year and cultivar, the analysis of variance for all of characteristics showed that sample size effect was not significant, enabling the use such a small sample for further investigations. The kernel trait with the highest variation for year was kernel width. The absolute variation of 1994 with respect to 1993 growing season was 30.9%. While kernel weight or volume did not correlate with test weight, a negative association with kernel length (r = -0.61, P = 0.05) and perimeter (r = -0.57, P = 0.05) was found. The kernel shape factors, rectangular aspect ratio (RAR) and circularity shape factor (CSF), showed a positive correlation with test weight (r = 0.51, P = 0.05 and r = 0.59, P = 0.05, respectively). The shape factors were negatively correlated both with kernel length and perimeter and positively with kernel width. A predictive model for test weight (TW = 38.7 + 5.1·ETW, where the estimated test weight [ETW] was computed as individual kernel weight/estimated kernel volume [EKV] ratio), was highly correlated with actual test weight values (r = 0.82, P = 0.001). The effectiveness of the linear model was confirmed when a set of 10 advanced lines of durum wheat were considered, although a slightly lower correlation (r = 0.73, P = 0.05) between actual and predicted test weight values was found. Because the extent of predictability of this approach might be more effective in early-generation lines, the application of the findings in a durum wheat breeding program would be advisable.  相似文献   

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