Effect of Wheat Genotype and Environment on Relationships Between Dough Extensibility and Breadmaking Quality

Dough extensibility affects processing ease, gas retention, and loaf volume of finished products. The Kieffer dough extensibility test was developed to assess extensibility of small dough samples and is therefore adapted for use in breeding programs. Information is lacking on relationships between wheat growing environments and dough properties measured by the Kieffer dough extensibility test. This study documents the variability of dough extensibility (Ext), maximum resistance to extension (Rmax), and area under the extensibility curve (Area) in relation to breadmaking quality, and the effect of wheat growing environments. Mixograph, Kieffer dough extensibility, and bake tests were performed on flour milled from 19 hard red spring wheat (Triticum aestivum L.) genotypes grown during three growing seasons (2007‐2009) at six South Dakota locations. Although both genotype and environment had significant effects on Kieffer dough extensibility variables, environment represented the largest source of variation. Among genotype means, Area was most correlated (r = 0.63) with loaf volume, suggesting that by selecting lines with increased Area, loaf volume should improve. Rmax was positively correlated (r = 0.58) with loaf volume among genotype means but negatively correlated (r = –0.80) among environmental means. Ext was positively correlated (r = 0.90) with loaf volume among environmental means. Weather variables were correlated with Rmax, Ext and loaf volume and therefore could help predict end‐use quality.     

Relationship of Bread Quality to Kernel,Flour, and Dough Properties

This study measured the relationship between bread quality and 49 hard red spring (HRS) or 48 hard red winter (HRW) grain, flour, and dough quality characteristics. The estimated bread quality attributes included loaf volume, bake mix time, bake water absorption, and crumb grain score. The best‐fit models for loaf volume, bake mix time, and water absorption had R² values of 0.78–0.93 with five to eight variables. Crumb grain score was not well estimated, and had R² values ≈0.60. For loaf volume models, grain or flour protein content was the most important parameter included. Bake water absorption was best estimated when using mixograph water absorption, and flour or grain protein content. Bake water absorption models could generally be improved by including farinograph, mixograph, or alveograph measurements. Bake mix time was estimated best when using mixograph mix time, and models could be improved by including glutenin data. When the data set was divided into calibration and prediction sets, the loaf volume and bake mix time models still looked promising for screening samples. When including only variables that could be rapidly measured (protein content, test weight, single kernel moisture content, single kernel diameter, single kernel hardness, bulk moisture content, and dark hard and vitreous kernels), only loaf volume could be predicted with accuracies adequate for screening samples.     

Modeling of Dough Mixing Profile Under Thermal and Nonthermal Constraint for Evaluation of Breadmaking Quality of Hard Spring Wheat Flour

This research was initiated to investigate associations between flour breadmaking traits and mixing and empirical dough rheological properties under thermal stress. Thirty hard spring wheat flour samples were analyzed by a Mixolab standard procedure. Mixolab profiles were divided into six different stages, and torque measurements of individual stages were modeled by nonlinear curve fitting using a compound of two solution searching procedures, multidimensional unconstrained nonlinear minimization and genetic algorithm. Mixing patterns followed exponential equations. Dough torque patterns under heat constraint, specifically dough thermal weakening and pasting profiles, were described by a sigmoid logistic equation as a function of time. Dough stability during heating appeared important for bread loaf volume increase from significant correlations between bread loaf volume and parameters generated from models of a dough thermal weakening stage. Multivariate continuum regression was employed to calibrate prediction models of baking traits using Mixolab parameters. Coefficients of determination estimated from prediction models and cross‐validation were greater than 0.98 for bake water absorption, mixing time, and bread loaf volume, indicating that the Mixolab parameters have a potential to enhance evaluation of flour breadmaking quality.     

Protein Composition‐Functionality Relationships for a Set of Argentinean Wheats

Relationships between flour functional properties and protein composition were studied using a set of 138 Argentinean wheat samples. Among different protein groups, the incremental increase of gliadin with increasing grain protein content was highest followed by polymeric protein with albumin‐globulin content much lower. Functional properties could be divided into two groups based on dependence on protein composition. Properties such as dough extensibility and bake test loaf volume correlated highly with the percentage of polymeric protein in the grain. Properties such as mixograph dough development time were best correlated with the percentage of polymeric protein in the protein (PPP). Alveograph tenacity showed no significant dependence on PPP. as found previously for extensigraph maximum resistance, but it was correlated with the percentage of unextractable polymeric protein in the protein. Energy (W) appeared to be a more useful alveograph parameter for predicting flour quality.     

Transgenic Enhancement of High‐Molecular‐Weight Glutenin Subunit 1Dy10 Concentration: Effects in Wheat Flour Blends and Sponge and Dough Baking

Dough strength is needed for efficient breadmaking quality. This property is strongly influenced in wheat (Triticum aestivum L.) by gluten seed storage proteins and, in particular, by high‐molecular‐weight (HMW) glutenin subunit composition. Experiments were designed to elevate expression of a key native HMW glutenin subunit (1Dy10) via genetic engineering and to determine whether resultant flours can be used in sponge and dough applications, the most common commercial bread‐baking procedure. Both unblended and blended samples from transgenic and nontransgenic sister lines were tested, with blended samples being formed by addition to a control sample. Dough properties, as determined by farinograph evaluation, were improved by the transgene‐encoded increases in 1Dy10 in both undiluted and blended flours. Mean farinograph stability of transgenic samples was twice that of the control, and blends with transgenic samples demonstrated increases in stabilities proportional to the amount of transgenic flour included. Mean farinograph quality numbers of transgenic samples, and of all blends containing transgenic flour, were significantly higher than both the control and all nontransgenic treatments. In the sponge and dough bake procedure, undiluted transgenic samples induced lower scores, relative to both control and undiluted nontransgenic samples, for water absorption, crumb body firmness, and loaf volume. In blends, however, the transgenic samples resulted in improvements in some sponge and dough loaf attributes, including loaf symmetry and crumb color score, without any concomitant loss of loaf volume in transgenic blends. These improved variables relate to finished product appearance and to consumer selection in markets. The use of transgenic flours with increased 1Dy10 glutenin content in commercial blends could provide advantages in sponge and dough bake applications.     

Levels of Protein and Protein Composition in Hard Winter Wheat Flours and the Relationship to Breadmaking

Protein and protein fractions were measured in 49 hard winter wheat flours to investigate their relationship to breadmaking properties, particularly loaf volume, which varied from 760 to 1,055 cm³ and crumb grain score of 1.0–5.0 from 100 g of flour straight‐dough bread. Protein composition varied with flour protein content because total soluble protein (SP) and gliadin levels increased proportionally to increased protein content, but albumins and globulins (AG), soluble polymeric proteins (SPP), and insoluble polymeric protein (IPP) levels did not. Flour protein content was positively correlated with loaf volume and bake water absorption (r = 0.80, P < 0.0001 and r = 0.45, P < 0.01, respectively). The percent SP based on flour showed the highest correlation with loaf volume (r = 0.85) and low but significant correlation with crumb grain score (r = 0.35, P < 0.05). Percent gliadins based on flour and on protein content were positively correlated to loaf volume (r = 0.73, P < 0.0001 and r = 0.46, P < 0.001, respectively). The percent IPP based on flour was the only protein fraction that was highly correlated (r = 0.62, P < 0.0001) with bake water absorption followed by AG in flour (r = 0.30, P < 0.05). Bake mix time was correlated positively with percent IPP based on protein (r = 0.86) but negatively with percent SPP based on protein (r = ‐0.56, P < 0.0001).     

SDS-Protein Gel Test for Prediction of Bread Loaf Volume

Flour dispersed in aqueous solutions of sodium dodecyl sulfate (SDS) forms a proteinaceous gel when centrifuged at high speed. The conventional methodology for SDS gel testing was modified to develop a small-scale (<1 g of flour or wheat meal) screening test for evaluation of the protein quality of wheat for breadmaking. The principal modification involved centrifugation with a swinging-bucket rotor to facilitate direct measurement of gel height, which is the primary test parameter. The effects of suspension temperature and time, centrifugation speed, sample size, and sieving of ground wheat or flour on the efficacy of the test were examined. Gel height, wet weight, and protein content were assessed as test parameters. In the standard test procedure that was developed, 0.67 g of flour or ground whole wheat was dispersed in 13.5 mL of 1.5% SDS solution for 15 min at 20°C, followed by centrifugation at 80,000 × g for 30 min. The test was evaluated using seven Canadian commercial wheat flours with diverse breadmaking quality. For the samples, gel height was strongly related to loaf volume (R² = 0.89 and 0.95 for flour and ground wheat, respectively). Sieving flour through a 75-μm sieve slightly increased the predictive power of the test (R² = 0.94). SDS gel height gave better discrimination of samples for prediction of loaf volume than did the traditional SDS sedimentation test. The performance of the sedimentation test improved when sieved ground wheat was used. The relationship between gel height or protein content and flour protein content was comparatively poor (R² = 0.25). The SDS gel test appears to primarily measure the effects of flour protein quality.     

Effect of Enzymatic Tempering of Wheat Kernels on Milling and Baking Performance

This study examined the effect of cell‐wall‐degrading enzymes added to temper water on wheat milling performance and flour quality. An enzyme cocktail consisting of cellulase, xylanase, and pectinase and five independent variables (enzyme concentration, incubation time, incubation temperature, tempered wheat moisture content, and tempering water pH) were manipulated in a response surface methodology (RSM) central composite design. A single pure cultivar of hard red winter wheat was tempered under defined conditions and milled on a Ross experimental laboratory mill. Some treatment combinations affected flour yield from the break rolls more than that from the reduction rolls. However, a maximum for flour yield was not found in the range of parameters studied. Though treatments did not affect the optimum water absorption for breadmaking, enzyme‐treated flours produced dough exhibiting shorter mixing times and slack and sticky textures compared with the control. Regardless of differences in mixing times, specific loaf volumes were not significantly different among treatments. Crumb firmness of bread baked with flour milled from enzyme‐treated wheat was comparable to the control after 1 day but became firmer during storage up to 5 days.     

Variability and Relationships Among Mixolab,Mixograph, and Baking Parameters Based on Multienvironment Spring Wheat Trials

Because of the large number of cultivars that require examination in the development of spring wheat (Triticum aestivum L.) cultivars, breeding programs use predictive methods to test end use quality. The Mixograph is a widely used predictive test with which end use quality of many genotypes can be assessed in a short time. By comparison, the Mixolab is a relatively new device with additional capability that might be used for the same purpose. Our objective was to document variability of, and relationships among, 20 parameters obtained from Mixolab, Mixograph, and bake tests. Tests were performed on flour from 18 genotypes grown in 20 environments. Both genotype and environment had significant effects on quality parameter values. Several Mixograph and Mixolab parameters were highly significantly correlated, particularly when genotype mean values over environments were considered. Correlations between loaf volume and Mixolab parameters within environments were inconsistent and suggest that average genotype values over environments will be most useful. For example, the correlation between Mixolab stability and loaf volume (r = 0.25, P < 0.001) was much higher when genotype averages (r = 0.70, P < 0.001) were considered. Our results show that selection for Mixolab stability and water absorption should help delineate and improve the selection of genotypes with greater loaf volume.     

Predicting Wheat Quality Characteristics and Functionality Using Near‐Infrared Spectroscopy

The 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.     

Effects of Pearling on Falling Number and α‐Amylase Activity of Preharvest Sprouted Spring Wheat

Preharvest sprouted wheat is often characterized by the falling number (FN) test. FN decreases in preharvest sprouted wheat as enzymatic degradation of the starchy endosperm increases. Wheat with FN values <250–275 is often discounted at the time of sale. The intent of this investigation was to evaluate the effects of debranning or pearling on the flour quality traits of five samples of wheat rated as low, med‐low, medium, med‐high, and sound that exhibited a range in FN values of 62–425 sec. Replicates of each sample were pearled for 30, 60, and 120 sec to remove portions of the outer bran layers before milling. FN was highly correlated with α‐amylase activity (r > ‐0.97) in the med‐low, medium, and med‐high FN sample sets as pearling time increased. FN increased in the medlow, medium, and med‐high FN samples by 128, 123, and 80%, respectively, after 120 sec of pearling. Pearling had no effect on flour FN of the low FN sample but α‐amylase activity was significantly decreased. Pearling had little or no effect on FN and α‐amylase activity of the sound sample. FN was moderately to strongly correlated with Rapid Visco Analyser (RVA), alveograph, and farinograph properties, and poorly correlated with protein content, flour yield, and bread loaf volume. In subsequent breadmaking studies, bread loaf volume, and crumb characteristics of flour from pearled wheat were not significantly different from loaf volume and crumb characteristics of flour from the corresponding nonpearled wheat.     

Distribution of Protein Composition in Bread Wheat Flour Mill Streams and Relationship to Breadmaking Quality

Wheat protein quantity and composition are important parameters for wheat baking quality. The objective of this study was to use fractionation techniques to separate the proteins of flour mill streams into various protein fractions, to examine the distribution of these protein fractions, and to establish a relationship between protein composition and breadmaking quality. Nine break streams, nine reduction streams, and three patent flours obtained from three samples of Nekota (a hard red winter wheat) were used in this study. A solution of 0.3M NaI + 7.5% 1-propanol was used to separate flour protein into monomeric and polymeric proteins. The protein fractions, including gliadin, albumin+globulin, HMW-GS, and LMW-GS, were precipitated with 0.1M NH₄Ac-MeOH or acetone. The fractions were statistically analyzed for their distribution in the mill streams. The quantities of total flour protein and protein fractions in flour were significantly different among mill streams. The ratio of polymeric to monomeric proteins in break streams was significantly greater than in the reduction streams. The relationship between protein composition and breadmaking quality showed that the quantities of total flour protein, albumin+ globulin, HMW-GS, and LMW-GS in flour were significantly and positively correlated with loaf volume. The ratio of HMW-GS to LMW-GS had little association with loaf volume. The gliadin content in total flour protein was negatively and significantly correlated with loaf volume. These results indicated that the quantity and composition of protein among the mill streams was different, and this resulted in differences in breadmaking quality.     

Environmental Influences on Flour Quality for Sheeted Noodles in Idaho 377s Hard White Wheat

Production of common wheat (Triticum aestivum L.) in the Pacific Northwest of the United States specifically for Asian noodle products is a relatively new goal for grain producers. We surveyed commercial fields of the hard white spring wheat cultivar Idaho 377s in two years to determine the variables contributing to Asian noodle quality and to validate previous observations made with small‐plot research. Fields were surveyed in 1998 and 1999 in two areas of the Snake River Plain of southeastern Idaho separated by ≈100 km, with both irrigated fields and rain‐fed fields sampled in both zones. Samples were evaluated for grain characteristics then milled and evaluated for flour quality, alkaline noodle color, and color and texture of nonalkaline Chinese (salted, neutral pH) noodles. Grain from rain‐fed fields produced brighter and more yellow alkaline noodles than grain from irrigated fields. Grain produced in rain‐fed fields also had lower peak flour pasting viscosity than grain produced in irrigated fields. Flour ash was lowest in grain from rain‐fed fields located in a higher elevation district (Upper Valley) and greatest in grain from irrigated fields located in a lower elevation district (Lower Valley). Noodle hardness and chewiness were greater in Chinese noodles made from grain produced in the Upper Valley than grain from the Lower Valley. Chinese noodle color had significant interaction with the location and irrigation management used for producing the grain. However, Chinese noodle brightness was consistently negatively correlated with flour protein concentration. The color and texture of noodles produced from flours milled from on‐farm commercial production was consistent with previous experiment station small‐plot research.     

Impact of Wheat Grain Selenium Content Variation on Milling and Bread Baking

Selenium (Se) is an essential micronutrient in animals. High levels of Se can accumulate in wheat grain, but it is not clear how high Se affects milling or baking. Low and high Se grain from the same hard red winter wheat cultivar was milled and used for breadbaking studies and Se analysis. Mill stream yields from the low and high Se wheat were comparable, as were flour yields. The amount of total grain Se retained in the flour mill streams was 71.2 and 66.4% for the low and high Se wheat, respectively. Proportionally, Se content in the bran, shorts, and the first reduction flour stream in high Se wheat was higher by 13–20% compared to the low Se wheat. Flour quality parameters including protein content, ash content, and farinograph traits were similar in low and high Se flours, although high Se flour mill streams exhibited lower farinograph stability. Breadbaking evaluations indicated that high Se had a deleterious effect on loaf volume. There was no evidence of significant Se loss after breadbaking with either low or high Se flour.     

Impact of Wheat Fiber on Frozen Dough Shelf Life and Bread Quality

Freezing and prolonged frozen storage of dough results in constant deterioration in the overall quality of the final product. In this study the effect of wheat bran and wheat aleurone as sources of arabinoxylan (AX) on the quality of bread baked from yeasted frozen dough was investigated. Wheat fiber sources were milled to pass through a 0.5 mm screen, prehydrated for 15 min, and incorporated into refined wheat flour at 15% replacement level. Dough products were prepared from refined flour (control A), whole wheat flour (control B), aleurone composite flour (composite flour A), and bran composite flour (composite flour B) and stored at –18°C for 28 weeks. Dough samples were evaluated for breadmaking quality at zero time, 14 weeks, and 28 weeks of storage. Quality parameters evaluated were loaf weight, loaf specific volume, and crumb firmness. Composite flour bread samples showed the most resistance to freeze damage (less reduction in the overall product quality), indicating a possible role of some fiber components (e.g., AX) in minimizing water redistribution in the dough system and therefore lessening adverse modifications to the gluten structure. The data suggest that the shelf life of frozen dough and quality of obtained bread can be improved with the addition of an AX source.     

Solvent Retention Capacity Values in Relation to Hard Winter Wheat and Flour Properties and Straight‐Dough Breadmaking Quality

Solvent retention capacity (SRC) was investigated in assessing the end use quality of hard winter wheat (HWW). The four SRC values of 116 HWW flours were determined using 5% lactic acid, 50% sucrose, 5% sodium carbonate, and distilled water. The SRC values were greatly affected by wheat and flour protein contents, and showed significant linear correlations with 1,000‐kernel weight and single kernel weight, size, and hardness. The 5% lactic acid SRC value showed the highest correlation (r = 0.83, P < 0.0001) with straight‐dough bread volume, followed by 50% sucrose, and least by distilled water. We found that the 5% lactic acid SRC value differentiated the quality of protein relating to loaf volume. When we selected a set of flours that had a narrow range of protein content of 12–13% (n = 37) from the 116 flours, flour protein content was not significantly correlated with loaf volume. The 5% lactic acid SRC value, however, showed a significant correlation (r = 0.84, P < 0.0001) with loaf volume. The 5% lactic acid SRC value was significantly correlated with SDS‐sedimentation volume (r = 0.83, P < 0.0001). The SDS‐sedimentation test showed a similar capability to 5% lactic acid SRC, correlating significantly with loaf volume for flours with similar protein content (r = 0.72, P < 0.0001). Prediction models for loaf volume were derived from a series of wheat and flour quality parameters. The inclusion of 5% lactic acid SRC values in the prediction model improved R² = 0.778 and root mean square error (RMSE) of 57.2 from R² = 0.609 and RMSE = 75.6, respectively, from the prediction model developed with the single kernel characterization system (SKCS) and near‐infrared reflectance (NIR) spectroscopy data. The prediction models were tested with three validation sets with different protein ranges and confirmed that the 5% lactic acid SRC test is valuable in predicting the loaf volume of bread from a HWW flour, especially for flours with similar protein contents.     

Whole Grain Wheat Flour Production Using an Ultracentrifugal Mill

Interest has been growing in whole grain products. However, information regarding the influence of the ultracentrifugal mill on whole grain flour quality has been limited. An experiment was conducted to produce whole wheat flour with hard red spring (HRS) wheat using an ultracentrifugal mill. This study determined the effect of centrifugal mill parameters as well as grain moisture (10–16%) on producing whole wheat flour and its final products. Mill parameters studied were rotor speed (6,000–15,000 rpm) and feed rate (12.5–44.5 g/min). Results showed that fine particle size (<150 µm) was favored by low seed moisture content (10–12%) and high rotor speed (12,000–15,000 rpm). Flour moisture content was positively related to seed moisture content. Wheat grain with low seed moisture content (10–12%) milled with high rotor speeds (12,000–15,000 rpm) produced desirable whole grain wheat flour quality, with 70–90% of fine particle size portion and low damaged starch (less than 11%). This whole wheat flour produced uniform and machinable dough that had low stickiness and formed bread with high loaf volume.     

Bran Characteristics and Bread‐Baking Quality of Whole Grain Wheat Flour

Variations in physical and compositional bran characteristics among different sources and classes of wheat and their association with bread‐baking quality of whole grain wheat flour (WWF) were investigated with bran obtained from Quadrumat milling of 12 U.S. wheat varieties and Bühler milling of six Korean wheat varieties. Bran was characterized for composition including protein, fat, ash, dietary fiber, phenolics, and phytate. U.S. soft and club wheat brans were lower in insoluble dietary fiber (IDF) and phytate content (40.7–44.7% and 10.3–17.1 mg of phytate/g of bran, respectively) compared with U.S. hard wheat bran (46.0–51.3% and 16.5–22.2 mg of phytate/g of bran, respectively). Bran of various wheat varieties was blended with a hard red spring wheat flour at a ratio of 1:4 to prepare WWFs for determination of dough properties and bread‐baking quality. WWFs with U.S. hard wheat bran generally exhibited higher dough water absorption and longer dough mixing time, and they produced smaller loaf volume of bread than WWFs of U.S. soft and club wheat bran. WWFs of two U.S. hard wheat varieties (ID3735 and Scarlet) produced much smaller loaves of bread (<573 mL) than those of other U.S. hard wheat varieties (>625 mL). IDF content, phytate content, and water retention capacity of bran exhibited significant relationships with loaf volume of WWF bread, whereas no relationship was observed between protein content of bran and loaf volume of bread. It appears that U.S. soft and club wheat bran, probably owing to relatively low IDF and phytate contents, has smaller negative effects on mixing properties of WWF dough and loaf volume of bread than U.S. hard wheat bran.     

Single-Kernel Characteristics of Hard Winter Wheats in Relation to Milling and Baking Quality

To investigate relationships of wheat single kernel (SK) characteristics with end-use properties, we used 12 hard winter wheat cultivars harvested at six regions in Kansas in 1993. Significant positive correlations occurred among wheat hardness parameters including near-infrared reflectance hardness score, SK hardness index (SK-HI), and SK peak force (SK-PF) obtained by the Single Kernel Characterization System (SKCS). The SKCS characteristics also were significantly correlated to conventional wheat quality parameters such as test weight, kernel density, and kernel sizing. Flour yields were significantly correlated with SK-PF, SK-HI, and SK weight (SK-WT), suggesting the usefulness of SKCS in evaluating milling quality. The negative correlation of milling score with the standard deviation of SK-HI and SK-PF indicated that uniformity of SK hardness is desirable for good milling performance. However, bread loaf volumes had significant negative correlations with SK diameter and SK-WT, mainly due to the inverse relationship between wheat protein contents and kernel weights or sizes. Loaf volume regression values, the changes in loaf volumes per one percentage point of flour protein, also had significant negative correlations with SK-HI, SK-PF, and SK-WT.     

Comparison of Quality Characteristics and Breadmaking Functionality of Hard Red Winter and Hard Red Spring Wheat

Various whole‐kernel, milling, flour, dough, and breadmaking quality parameters were compared between hard red winter (HRW) and hard red spring (HRS) wheat. From the 50 quality parameters evaluated, values of only nine quality characteristics were found to be similar for both classes. These were test weight, grain moisture content, kernel size, polyphenol oxidase content, average gluten index, insoluble polymeric protein (%), free nonpolar lipids, loaf volume potential, and mixograph tolerance. Some of the quality characteristics that had significantly higher levels in HRS than in HRW wheat samples included grain protein content, grain hardness, most milling and flour quality measurements, most dough physicochemical properties, and most baking characteristics. When HRW and HRS wheat samples were grouped to be within the same wheat protein content range (11.4–15.8%), the average value of many grain and breadmaking quality characteristics were similar for both wheat classes but significant differences still existed. Values that were higher for HRW wheat flour were color b*, free polar lipids content, falling number, and farinograph tolerance. Values that were higher for HRS wheat flour were geometric mean diameter, quantity of insoluble polymeric proteins and gliadins, mixograph mix time, alveograph configuration ratio, dough weight, crumb grain score, and SDS sedimentation volume. This research showed that the grain and flour quality of HRS wheat generally exceeds that of HRW wheat whether or not samples are grouped to include a similar protein content range.