Flour Characteristics Related to Optimum Water Absorption of Noodle Dough for Making White Salted Noodles

Physicochemical properties of 34 wheat flours with various classes and different protein contents were related to optimum water absorption of noodle dough. Club and soft wheat flours generally exhibited higher water absorption (34–37%) of noodle dough than hard wheat flours (31–35%). Optimum water absorption of noodle dough in three hard wheat flours with five different protein contents was 33–37%. Optimum water absorption was negatively correlated with flour protein content and SDS sedimentation volume. Physical properties of flour, damaged starch content, NIRS hardness and water retention capacity, influenced optimum water absorption of noodle dough from club, soft and hard wheat flours. A prediction equation developed using protein content, water retention capacity and SDS sedimentation volume of flour provides a reliable estimation of the optimum absorption of noodle dough for making noodles.     

Relationship Between Protein Characteristics and Instant Noodle Making Quality of Wheat Flour

We investigated the relationship between the protein content and quality of wheat flours and characteristics of noodle dough and instant noodles using 14 hard and soft wheat flours with various protein contents and three commercial flours for making noodles. Protein content of wheat flours exhibited negative relationships with the optimum water absorption of noodle dough and lightness (L*) of the instant noodle dough sheet. Protein quality, as determined by SDS sedimentation volume and proportion of alcohol‐ and salt‐soluble protein of flour, also influenced optimum water absorption and yellow‐blueness (b*) of the noodle dough sheet. Wheat flours with high protein content (>13.6%) produced instant noodles with lower fat absorption, higher L*, lower b*, and firmer and more elastic texture than wheat flours with low protein content (<12.2%). L* and free lipid content of instant noodles were >76.8 and <20.8% in hard wheat flours of high SDS sedimentation volume (>36 mL) and low proportion of salt‐soluble protein (<12.5%), and <75.7 and >21.5% in soft wheat flours with low SDS sedimentation volume (<35 mL) and a high proportion of salt‐soluble protein (>15.0%). L* of instant noodles positively correlated with SDS sedimentation volume and negatively correlated with proportion of alcohol‐ and salt‐soluble protein of flour. These protein quality parameters also exhibited a significant relationship with b* of instant noodles. SDS sedimentation volume and proportion of salt‐soluble protein of flours also exhibited a significant relationship with free lipid content of instant noodles (P < 0.01 and P < 0.001, respectively). Protein quality parameters of wheat flour, as well as protein content, showed significant relationship with texture properties of cooked instant noodles.     

Comparison of Asian Noodles from Some Hard White and Hard Red Wheat Flours

Asian noodles were prepared by an objective laboratory method that included adding optimum water to the dry ingredients, mixing the ingredients to homogeneous salt distribution, and sheeting of the dough under low shear stress. The lightness (L*) values of alkaline‐ and salt‐noodle doughs made from 65% extraction hard white wheat flours (except KS96HW115 flour at ≈70% extraction) were higher than those from 60% extraction hard red wheat flours (except Karl 92 flour at ≈70% extraction). A hard white spring wheat, ID377s, and a Kansas line of hard white winter wheat, KS96HW115, to be released in 2000, gave the highest L* values for dough sheets stored for 2 and 24 hr at 25°C. Cooking losses were 5–9 percentage points higher for alkaline noodles than salt noodles, but the cooking yields of the two types of Asian noodles were almost the same. Cooked alkaline noodles made from a high‐swelling flour (SP₉₃≈21 g/g) gave higher tensile strength than those made from several low‐swelling flours (SP₉₃ ≈15 g/g) with the same protein contents (≈12.5%). However, the cooked salt noodles gave the same tensile strength.     

Quantitative and Qualitative Role of Added Gluten on White Salted Noodles

A commercial gluten and glutens isolated from four soft and four hard wheat flours were incorporated into a hard and a soft white flour by replacement to directly determine the quantitative and qualitative role of gluten proteins in making noodles. Gluten incorporation (6%) decreased water absorption of noodle dough by 3%, shortened the length of the dough sheet by 15 and 18%, and increased the thickness of the dough sheet by 18 and 20% in soft and hard wheat flour, respectively. Noodles imbibed less water and imbibed water more slowly during cooking with gluten incorporation, which resulted in a 3‐min increase in cooking time for both soft and hard wheat noodles. Despite the extended cooking time of 3 min, noodles incorporated with 6% gluten exhibited decreases in cooking loss by 15% in soft wheat. In hard wheat flour, cooking loss of noodles was lowest with 2% incorporation of gluten. Tensile strength of fresh and cooked noodles, as well as hardness of cooked noodles, increased linearly with increase in gluten incorporation, regardless of cooking time and storage time after cooking. While hardness of cooked noodles either increased or showed no changes during storage for 4 hr, tensile strength of noodles decreased. There were large variations in hardness and tensile strength of cooked noodles incorporated with glutens isolated from eight different flours. Noodles incorporated with soft wheat glutens exhibited greater hardness and tensile strength than noodles with hard wheat glutens. Tensile strength of cooked noodles incorporated with eight different glutens negatively correlated with SDS sedimentation volume of wheat flours from which the glutens were isolated.     

Investigation of a Small‐Scale Asymmetric Centrifugal Mixer for the Evaluation of Asian Noodles

A high throughput centrifugal mixer capable of using smaller amounts of flour (50 g) was evaluated for the production of oriental alkaline noodles. The unit requires a small footprint on a laboratory bench and offers variable speed mixing (300–3,500 rpm) for 5–60 sec. Three different mixing bowls, plain, pin, and paddle, were evaluated for the small‐scale production of alkaline noodles using straight‐grade flour derived from Canada Western Red Spring (CWRS) and Canada Prairie White Spring (CPSW) wheat. Under optimized mixing conditions (3,000 rpm for 30 sec), the pin and paddle bowls produced noodle dough with crumb size distribution and adhesion characteristics consistent with commercial requirements. The plain bowl produced dough with larger undesirable dough chunks and showed excessive heat buildup. Noodle sheets produced from this dough were not comparable in color characteristics to conventionally produced noodle sheets. Noodles prepared using the paddle mixer also displayed some significantly different color and texture characteristics than conventionally prepared noodles. However, raw noodle sheets or cooked noodles of either wheat class, prepared using the pin bowl mixer, displayed color values (L*, a*, and b*) at 2 and 24 hr and cooked noodle texture characteristics (bite, chewiness, resistance to compression, and recovery) comparable to a conventional laboratory‐scale Hobart type mixer. In addition to the very short mixing time and small equipment footprint for the centrifuge mixer, rapid throughput is enhanced by the ability to rapidly clean or interchange bowls and to potentially vary sample size to as little as 5 g. These attributes should be particularly useful in earlier generation breeder programs where large numbers of samples require rapid screening.     

Whey Protein Concentrate Treated with Heat or High Hydrostatic Pressure in Wheat-Based Products

Commercial whey protein concentrate (CWPC) treated with heat or with high hydrostatic pressure (HHP) was incorporated by replacement into wheat flour, and its effects on dough rheology and the quality of cookies, noodles, and bread were evaluated. Wheat flour fortified with heat- or HHP-treated CWPC produced smaller cookies than those fortified with untreated CWPC. Increasing the fortification level of heat- or HHP-treated CWPC from 5 to 10% further decreased cookie diameter. The water absorption for noodle dough decreased by 5% with 10% fortification of untreated CWPC. Both heat- and HHP-treated CWPC increased water absorption from 33% in the control to 35.8%. Incorporation of untreated CWPC decreased the lightness (L*) value of Cantonese noodle dough, while dough fortified with heat- or HHP-treated CWPC had higher L* values compared to those of the control. Yellowness (b*) was improved with incorporation of both untreated and treated CWPC. Cooking loss of Cantonese noodles fortified with untreated or heat- or HHP-treated CWPC was comparable to or lower than that of the control. Incorporation of untreated CWPC increased hardness and cohesiveness of Cantonese noodles. Noodles fortified with heat- or HHP-treated CWPC had similar hardness and were softer than the control and the noodles fortified with untreated CWPC. Wheat flour fortified with 10% untreated CWPC produced wet and sticky bread dough and a small loaf (730 mL). Handling properties of dough were improved and bread volume was increased by 50 mL when heat- or HHP-treated CWPC was incorporated. Incorporation of 10% CWPC increased protein content of bread up to 20.2% and also increased the proportion of essential amino acids.     

Effect of Processing,Formula and Measurement Variables on Alkaline Noodle Color—Toward An Optimized Laboratory System

A standardized laboratory method for assessing the color potential of flours for yellow alkaline (Cantonese) noodles is needed, especially for evaluating large numbers of small‐scale samples such as found in wheat breeding populations. To develop such a method, a number of processing and formula parameters were varied and judged for optimum level based on 1) discrimination and mean separation of flours, 2) sensitivity to minor variation in the protocol parameter, 3) practicality and simplicity for the technician, and 4) time efficiency. Four flours milled from single‐cultivar grain lots representing two with good and two with poor color potential were made into alkaline noodle sheets varying in thickness of 0.75–2.00 mm, water absorption of 33.0–39.0%, mixing time of 2–6 min, and NaCl levels of 0–4% (all flour weight basis). Commission Internationale de l'Eclairage (CIE) tristimulus color space (L*, a*, b*) values were measured at 0–24 hr using white, yellow, and black background tiles. Noodle sheet side and a dough resting period were examined. The flours themselves were a consistently large, significant source of variation for color, especially lightness (L*). Based on the optimization criteria, a noodle sheet thickness of 1.5–2.0 mm, an optimum to slightly over optimum water absorption (36% for the flours in this study) with some adjustment for protein content and dough handling properties, a mixing time of 4 min, no dough resting period, and 2% NaCl were selected. Color measurement at 24 hr on a white or otherwise light‐colored background tile was judged best using a consistent side of the noodle sheet. Resting doughs for 1 hr slightly improved handling and sheeting characteristics but was not included for time efficiencies.     

Suitability of Ontario‐Grown Hard and Soft Wheat Flour Blends for Noodle Making

This study evaluated the blending of flours made from an Ontario hard red winter wheat (HWF) and an Ontario soft red winter wheat (SWF) and compared it with a commercial standard noodle flour (control) made from Canadian Western Hard Red Spring wheat to assess the impact on white salted noodle‐making performance and texture of cooked noodles. Flour characteristics, gluten aggregation, and starch pasting properties were assessed with a farinograph, GlutoPeak tester, and Rapid Visco Analyzer, respectively. The machinability of dough was evaluated with an SMS/Kieffer rig attached to a TA.XT Plus texture analyzer. Tensile and bite tests of cooked noodles were also conducted. Blending HWF with standard noodle flour decreased gluten strength and dough extensibility linearly proportional to the blend ratio, whereas a curvilinear response from blending SWF with standard noodle flour was observed. HWF demonstrated more favorable pasting properties except for lower peak viscosity for noodle making than standard noodle flour. Below a 20% blend ratio with HWF, no significant changes were seen on dough extensibility, cooking loss, tensile properties, and bite testing parameters of cooked noodles. It can be concluded that blending HWF up to a 20% level caused no significant change in the processing properties of dough and cooked noodle quality. The results also showed that the GlutoPeak tester is a sensitive tool for evaluating gluten strength in wheat flour.     

Refrigerated Storage of Yellow Alkaline Durum Noodles: Impact on Color and Texture

Durum wheat straight‐grade flour samples, representing the cultivars Commander and Strongfield, a composite cargo mixture of Canada Western Amber Durum cultivars and a Japanese commercial durum flour were used to make yellow alkaline noodles. A Canada Western Red Spring common wheat composite straight‐grade flour was included in the study for comparative purposes. Alkaline noodles were prepared using 1% w/w kansui reagent (sodium and potassium carbonates, 9:1) and stored for 1, 2, 3 and 7 days at 4°C to duplicate a normal convenience store operation. The raw noodle color of the durum alkaline noodles exhibited significantly better noodle brightness, L*, and yellowness, b*, as compared to noodles prepared from common wheat at all storage periods. The number of discolored specks in the durum flour based noodles was significantly lower as well as significantly lighter than those of common wheat at all time intervals. Noodles prepared from Commander, Strongfield, or the cargo composite flours displayed significantly lower water uptake during cooking than both the commercial durum flour and the common wheat noodles. The commercial durum flour noodles displayed the thinnest cooked noodles, while the common wheat flour noodles were the thickest. Evaluation of cooked noodle texture, immediately after production and subsequent storage of the raw noodles at 4°C for 1, 2 and 3 days before cooking showed a general increase in maximum cutting stress (MCS) with storage. Noodles prepared from Commander flour consistently display MCS values exceeding those of CWRS as well as the highest resistance to compression (RTC) and recovery (REC) measurements. The visual improvements in noodle brightness, enhanced yellowness, reduced speck numbers and darkness in combination with equivalent to improved cooked noodle texture attributes compared with common wheat flour suggests that durum flours are an ideal material for fresh, refrigerated yellow alkaline noodles.     

Effects of Allelic Variations in Wx‐1, Glu‐D1, Glu‐B3, and Pinb‐D1 Loci on Flour Characteristics and White Salted Noodle‐Making Quality of Wheat Flour

Doubled haploid wheat lines developed from a cross between a hard white winter wheat variety of normal starch endosperm and a waxy wheat variety were used to determine the effects of allelic variation in Wx‐1, Glu‐D1, Glu‐B3, and Pinb‐D1 loci on physiochemical properties of flour, noodle dough properties, and textural quality of cooked noodles. Milling yield, damaged starch content, protein content, and SDS sedimentation volume of flour were influenced the most by allelic composition of Pinb‐D1 loci, less by Wx‐1 loci, and least by Glu‐B3. Wheat lines carrying Pinb‐D1b or Glu‐B3h alleles exhibited higher milling yield and damaged starch content of flour than those with Pinb‐D1a and Glu‐B3d alleles. Wheat lines carrying the Pinb‐D1b allele were higher in protein content and SDS sedimentation volume than those carrying Pinb‐D1a. Mixograph water absorption was largely influenced by allelic composition of Wx‐1 loci, whereas mixograph mixing time and mixing tolerance were predominantly determined by allelic composition of Glu‐D1 loci. Amylose content and pasting properties of starch were mainly determined by allelic composition of Wx‐1 loci with little influence by allelic compositions of Glu‐D1, Glu‐B3, and Pinb‐D1 loci. Allelic composition of Wx‐1 loci contributed 53.4% of the variation in optimum water absorption of noodle dough and 26.7% of the variation in thickness of the noodle dough sheet. The variation of 7.8% in optimum water absorption of noodle dough was contributed by the allelic composition of Pinb‐D1 loci. Allelic composition of Wx‐1 loci was responsible for 73.2, 74.4, and 59.6% in the variation of hardness, springiness, and cohesiveness of cooked noodles, respectively. Cohesiveness of cooked noodles was also influenced by the allelic compositions of Glu‐B3 and Pinb‐D1 loci to a smaller extent.     

Quality Characteristics of Fresh and Dried White Salted Noodles Enriched with Flour from Hull‐less Barley Genotypes of Diverse Amylose Content

Fresh and dried white salted noodles (WSN) were prepared by incorporating up to 40% flour from hull‐less barley (HB) genotypes with normal amylose, waxy, zero amylose waxy (ZAW), and high amylose (HA) starch into a 60% extraction Canada Prairie Spring White (cv. AC Vista) wheat flour. The HB flours, depending on genotype, contained four to six times the concentration of β‐glucan of the wheat flour, offering potential health benefits. The HB‐enriched noodles were made with conventional equipment without difficulty. Noodles containing 40% HB flour required less work input during sheeting, probably due to higher optimum water absorption and weakening of the dough due to dilution of wheat gluten. The addition of HB flour had a negative impact on WSN color and appearance, as evident from decreased brightness, increased redness, and more visible specking. The impact of HB flour on cooked WSN texture varied by starch type. Enrichment with HA or normal starch HB flour produced WSN with bite and chewiness values equivalent to or superior to the wheat flour control. Addition of waxy and ZAW HB flour resulted in WSN with lower values for bite and chewiness. The diversity of HB starch types allows tailoring of WSN texture to satisfy specific markets. HB flour also has potential as an ingredient in novel noodle products targeting health‐conscious consumers who associate darker colored cereal‐based foods with superior nutritional composition.     

Alkaline‐Carbonate Noodles from Hard Winter Wheat Flours Varying in Protein,Swelling Power,and Polyphenol Oxidase Activity

The effects of wheat protein and starch on yellow‐alkaline noodles have not been fully clarified. Twenty‐four hard winter wheats with varying protein, hot‐water swelling power (SP₉₅), and polyphenol oxidase (PPO) activity were milled into long‐patent and short‐patent flours. Protein, SP₉₅, and PPO activity in the 48 flours were 8.2–12.9%, 16.2–24.1 g/g, and 80–157 ΔA₄₈₀/mg of protein/min, respectively. Lightness of raw noodles declined with increasing protein and PPO levels but yellowness decreased and then increased. Tensile force to break the cooked noodles was positively correlated with SP₉₅ and protein. Compression (50%) force of noodles made from flour with high SP₉₅ ≈21 g/g, averaged ≈20% below those made from low SP₉₅ ≈17 g/g of flour. Compression force was measured in the long dimension of a single noodle strand using a rectangular probe. The instrumental measurements suggest that alkaline noodles made from a single‐null partial‐waxy wheat with medium SP₉₅ ≈19.9 g/g will have a tender bite and a cohesive texture compared with those from a low SP₉₅ wheat with a hard bite and fracturable texture. Furthermore, alkaline noodles from a double‐null partial‐waxy wheat with high SP₉₅ will have an extra soft bite unless flour protein is above ≈12.5%. Hard‐white, dual‐purpose wheat should have a low level of PPO and, depending on the preferred noodle‐eating texture, a low to medium SP₉₅ level. Such wheats with medium protein levels (11–12%) are well suited for alkaline noodles because of improved color and surface smoothness, whereas the same wheats with 12–13% protein are well suited for bread. Wheats with medium SP₉₅ also reduce cooking loss and increase cooked yield.     

Great Northern Bean Could Improve the Nutritional Value of Instant Noodles

Instant noodles were prepared by substituting hard red winter (HRW) wheat flour with Great Northern bean powder (GNBP) at selected levels (0–60%) using a pilot‐scale noodle processing machine. The functional properties, water absorption, water solubility, and pasting profiles of flour mixtures were tested to verify the process tolerances of ingredients. Prepared noodle samples were evaluated for color, cooking quality, texture, and sensory properties. Slight color differences, an increased cooking loss, and reduced chewiness, cohesiveness, and hardness were observed in cooked noodles that were prepared with GNBP up to 25% of HRW wheat flour weight. The results suggest that HRW wheat flour could be replaced up to 20% (w/w) with GNBP, while still using the conventional processing conditions, to improve the product nutritional value (i.e., increased protein and fiber contents and reduced fat content) (P < 0.05).     

Effects of Flour Extraction Rate,Added Water,and Salt on Color and Texture of Chinese White Noodles

Both cultivar and noodle composition and preparation have important effects on noodle quality. In this study, the effects of flour extraction rate (50, 60, and 70%), added water (33, 35, and 37%), and salt concentration (0, 1, and 2%, w/w) on color and texture of Chinese white noodle (CWN) were investigated using flour samples from five leading Chinese wheat cultivars. The five samples showed large variations in protein content, ash content, flour color, farinograph, and extensigraph parameters, and starch pasting properties. Analyses of variance indicated that cultivar, flour extraction rate, level of water addition, salt concentration, and the interactions had significant effects on color of raw noodle sheets and color and textural properties of CWN. Cultivar and water addition were more important sources of variation than flour extraction rate and salt concentration. The brightness (L*) and redness (a*) values of raw noodle sheets were significantly reduced and increased, respectively, as flour extraction rate increased from 50 to 70%, and noodle scores were slightly higher at flour extraction rates of 50%. Water addition showed different effects on raw noodle sheet color at 2 and 24 hr, and a significant improvement was observed for noodle appearance, firmness, viscoelasticity, smoothness, and total score as water addition increased from 33 to 37%. L* of raw noodle sheets, and firmness and viscoelasticity of cooked noodles, were significantly improved, but noodle flavor significantly deteriorated as salt concentration increased from 0 to 2%; 1% salt produced the highest noodle score. Thus, the recommended composition for laboratory preparation of CWN is 60% flour extraction, 35% water addition, and 1% salt concentration.     

Milling Quality and White Salt Noodle Color of Chinese Winter Wheat Cultivars

Improvement of milling quality is an important aspect in wheat breeding programs. However, the milling quality of Chinese wheats remains largely unexplored. Fifty‐seven Chinese winter wheat cultivars from four regions were used to investigate the variation of milling quality parameters and to determine the associations between milling quality traits and color of noodle sheet. Substantial variation was presented for all measured parameters in this germplasm pool. Complete soft, hard, and medium‐hard types were observed. Soft wheat and hard wheat show significant differences in flour ash content, flour bran area, and flour color grade. No simple trait can be used to select for flour milling quality. High flour ash content and bran speck area contributed negatively to brightness of dry flour. Correlation coefficients (r) between L* value of dry flour and flour ash content and bran speck area were ‐0.47 and ‐0.65 for hard cultivars, and ‐0.51 and ‐0.72 for soft cultivars, respectively. Flour color grade (FCG) was significantly and positively associated with bran speck area; r = 0.56 and 0.73 for hard and soft wheats, respectively. There was a high correlation between FCG and L* value of flour water slurry (r = ‐0.95). Strong associations were also established between milling quality index (MQI) and FCG, L* value of dry flour, flour‐water slurry, and white salted noodle sheet for both hard and soft wheats. In conclusion, substantial progress could be achieved in improvement of milling quality in Chinese winter wheats through genetic selection, and FCG and MQI could be two important parameters for evaluation of milling quality in breeding programs.     

Effect of Amaranthus and Buckwheat Proteins on Wheat Dough Properties and Noodle Quality

Isoelectric protein concentrates (IPC) were prepared from one buckwheat (Fagopyrum esculentum) and five Amaranthus genotypes. Their effect on the mixing properties of a wheat flour was studied. Mixograph and dynamic oscillatory measurements showed significant increases in dough strength with the addition of 2 and 4% IPC, correlated to the water-insoluble fraction level of the IPC. The same IPCs were used at 2% level to supplement a wheat flour in making Chinese dry noodles. Measurable changes in both the raw and cooked noodle color were observed, and the change caused by addition of buckwheat IPC was substantial. Some of the IPCs caused an increase in cooking loss and only one caused an increase in weight, while increase in volume of the cooked noodles was not significantly affected. The changes in the rheological properties of cooked noodles due to addition of IPCs were measured. Overall, their effects were favorable, but the changes were statistically significant in only a few cases. The substantial dough-strengthening effect of the IPCs was hence not effectively translated into improved cooked noodle quality, and possible reasons for this are discussed.     

Protein Quality of Wheat Desirable for Making Fresh White Salted Noodles and Its Influences on Processing and Texture of Noodles

Protein characteristics of wheat flours from various wheat classes, and of commercial flours for making noodles, were evaluated to determine the effects of protein content and quality on processing and textural properties of white salted noodles, as well as to identify protein quality required for making white salted noodles. SDS sedimentation volume based on constant protein weight, mixograph mixing time, and proportions of salt‐ and alcohol‐soluble protein of three commercial flours for making noodles were more similar to those of hard wheat than to soft wheat flours. SDS sedimentation volume of commercial flours for making noodles based on constant protein weight ranged from 38.5 to 40.0 mL and was higher than those of most soft wheat flours. Mixograph mixing time and proportion of salt‐soluble protein of hard and commercial flours for making noodles were >145 sec and mostly <13.8%, respectively, while those of club and soft wheat flours were < 95 sec and >15.0%. Both protein content and protein quality, as determined by SDS sedimentation volume based on constant protein weight, mixograph mixing time, proportion of salt‐soluble protein, and score of HMW‐GS compositions correlated with optimum water absorption of noodle dough and hardness of cooked white salted noodles.     

Relationship Between Physicochemical Properties of Wheat Flour,Wheat Protein Composition,and Textural Properties of Cooked Chinese White Salted Noodles

Physicochemical properties and protein composition of 39 selected wheat flour samples were evaluated and correlated with the textural properties of Chinese hard‐bite white salted noodles. Flour samples were analyzed for their protein and wet gluten contents, sedimentation volume, starch pasting properties, and dough mixing properties by farinograph and extensigraph. Molecular weight distribution of wheat flour proteins was determined with size‐exclusion (SE) HPLC, SDS‐PAGE, and acid‐PAGE. Textural properties of Chinese hard‐bite white salted noodles were determined through texture profile analysis (TPA). Hardness, springiness, gumminess, and chewiness of cooked noodles were found to be related to the dough mixing properties. Both protein content and protein composition were found to be related to TPA parameters of noodles. The amount of total flour protein was positively correlated to hardness, gumminess, and chewiness of noodles. The absolute amounts of different peak proteins obtained from SE‐HPLC data showed positive correlations with the hardness, gumminess, chewiness, and springiness of noodles. The proportions of these peak proteins were, however, not significantly related to texture parameters. The proportions of low‐molecular‐weight glutenins/gliadins and albumins/globulins, as observed from SDS‐PAGE, were correlated positively and negatively, respectively, to the hardness, gumminess, and chewiness of cooked noodles. Among the alcohol‐soluble proteins (from acid‐PAGE data), β‐gliadins showed strong correlations with the texture properties of cooked noodles. For the selected flour samples, the total protein content of flour had a stronger relationship with the noodle texture properties than did the relative proportion of different protein subgroups. Prediction equations were developed for TPA parameters of cooked noodles with SE‐HPLC and rapid visco analysis data of the 30 flour samples, and it was found that about 75% of the variability in noodle hardness, gumminess, and chewiness values could be explained by protein composition and flour pasting properties combined together. About 50% of the variations in cohesiveness and springiness were accounted for by these prediction equations.     

Effects of Protein Content and Composition on White Noodle Making Quality: Color

Wheat cultivars, representing three winter and three spring wheats were grown in western Canada with six levels of nitrogen fertilizer and flours were prepared from them with an extraction rate of 65%. Using a chromameter, flour color and the color of uncooked white noodle sheets made from these flours with different resting times were assessed. The cooked noodle sheet color was also assessed. While protein content initially declined with added nitrogen and increased with further nitrogen addition, brightness (L*) of flour decreased and redness (a*) and yellowness (b*) increased. Positive correlation coefficients of flour brightness with particle size index (PSI) were also observed. Flour redness (a*) and yellowness (b*) were also affected by flour moisture content, whereas L* values were not significantly correlated with moisture contents. For the uncooked white noodle sheet, as protein content increased brightness decreased but there was an increase in a* and b* values. Thus, the L* value for noodle sheets was negatively correlated with the a* and b* values. The percentages of monomeric protein and soluble glutenin in flour were equal to or better than protein content in relation to most noodle sheet color characters. Uncooked noodle sheet brightness decreased, while redness and yellowness increased with rest time. In general, uncooked white noodle sheets prepared from different wheat flours can be ranked in terms of brightness and yellowness within each level of nitrogen fertilization.     

Structural Modifications of Gluten Proteins in Strong and Weak Wheat Dough During Mixing

The network‐forming attributes of gluten have been investigated for decades, but no study has comprehensively addressed the differences in gluten network evolution between strong and weak wheat types (hard and soft wheat). This study monitored changes in SDS protein extractability, SDS‐accessible thiols, protein surface hydrophobicity, molecular weight distribution, and secondary structural features of proteins during mixing to bring out the molecular determinants of protein network formation in hard and soft wheat dough. Soft wheat flour and dough exhibited greater protein extractability and more accessible thiols than hard wheat flour and dough. The addition of the thiol‐blocking agent N‐ethylmaleimide (NEM) resulted in similar results for protein extractability and accessible thiols in hard and soft wheat samples. Soft wheat dough had greater protein surface hydrophobicity than hard wheat and exhibited a larger decrease in surface hydrophobicity in the presence of NEM. Formation of high‐molecular‐weight (HMW) protein in soft wheat dough was primarily because of formation of disulfides among low‐molecular‐weight (LMW) proteins, as indicated by the absence of changes in protein distribution when NEM was present, whereas in hard wheat dough the LMW fraction formed disulfide interaction with the HMW fraction. Fourier transform infrared spectroscopy indicated formation of β‐sheets in dough from either wheat type at peak mixing torque. Formation of β‐sheets in soft wheat dough appears to be driven by hydrophobic interactions, whereas disulfide linkages stabilize secondary structure elements in hard wheat dough.