Influence of Starch and Gluten Characteristics on Rheological Properties of Wheat Flour Gel at Small and Large Deformation

Starch and gluten were isolated from 10 wheat cultivars or lines with varied amylose content. The rheological properties of 30% wheat flour gel, starch gel, and the gel of isolated gluten mixed with common starch were determined in dynamic mechanical testing under shear deformation, creep‐recovery, and compression tests under uniaxial compression. Variation of wheat samples measured as storage shear modulus (G′), loss shear modulus (G″), and loss tangent (tan δ = G″/G′) was similar between flour and starch gels and correlated significantly between flour and starch gel. The proportion of acetic acid soluble glutenin exhibited a significant relationship with tan δ of gluten‐starch mixture gel. The small difference in amylose content strongly affected the rheological parameters of flour gels in creep‐recovery measurement. Wheat flour gel with lower amylose content showed higher creep and recovery compliance that corresponded to the trend in starch gel. Compressive force of flour gel at 50 and 95% strain correlated significantly with that of starch gel. Gel mixed with the isolated gluten from waxy wheat lines appeared to have a weaker gel structure in dynamic viscoelasticity, creep‐recovery, and compression tests. Starch properties of were primarily responsible for rheological changes in wheat flour gel.     

Characteristics of Noodles and Bread Prepared from Double‐Null Partial Waxy Wheat

Double‐null partial waxy wheat (Triticum aestivum L.) flours were used for isolation of starch and preparation of white salted noodles and pan bread. Starch characteristics, textural properties of cooked noodles, and staling properties of bread during storage were determined and compared with those of wheat flours with regular amylose content. Starches isolated from double‐null partial waxy wheat flours contained 15.4–18.9% amylose and exhibited higher peak viscosity than starches of single‐null partial waxy and regular wheat flours, which contained 22.7–25.8% amylose. Despite higher protein content, double‐null partial waxy wheat flours, produced softer, more cohesive and less adhesive noodles than soft white wheat flours. With incorporation of partial waxy prime starches, noodles produced from reconstituted soft white wheat flours became softer, less adhesive, and more cohesive, indicating that partial waxy starches of low amylose content are responsible for the improvement of cooked white salted noodle texture. Partial waxy wheat flours with >15.1% protein produced bread of larger loaf volume and softer bread crumb even after storage than did the hard red spring wheat flour of 15.3% protein. Regardless of whether malt was used, bread baked from double‐null partial waxy wheat flours exhibited a slower firming rate during storage than bread baked from HRS wheat flour.     

Comparison of Physical Properties of Wheat Starch Gels with Different Amylose Content

The effects of amylose content and other starch properties on concentrated starch gel properties were evaluated using 10 wheat cultivars with different amylose content. Starches were isolated from grains of two waxy and eight nonwaxy wheat lines. The amylose content of waxy wheat lines was 1.4–1.7% and that of nonwaxy lines was 18.5–28.6%. Starch gels were prepared from a concentrated starch suspension (30 and 40%). Gelatinized starch was cooled and stored at 5°C for 1, 8, 16, 24, and 48 hr. The rheological properties of starch gels were studied by measuring dynamic viscoelasticity with parallel plate geometry. The low‐amylose starch showed a significantly lower storage shear modulus (G′) than starches with higher amylose content during storage. Waxy starch gel had a higher frequency dependence of G′ and properties clearly different from nonwaxy starches. In 40% starch gels, the starch with lower amylose showed a faster increase in G′ during 48 hr of storage, and waxy starch showed an extremely steep increase in G′. The amylose content and concentration of starch suspension markedly affected starch gel properties.     

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.     

Quality Characteristics of Yellow Alkaline Noodles Enriched with Hull‐less Barley Flour

Roller milled flours from eight genotypes of hull‐less barley (HB) with normal, waxy, zero amylose waxy (ZAW), and high amylose (HA) starch were incorporated at 20 and 40% (w/w) with a 60% extraction Canada Prairie Spring White (CPSW, cv. AC Vista) wheat flour to evaluate their suitability as a blend for yellow alkaline noodles (YAN). The barley flour supplemented noodles were prepared using conventional equipment. Noodles containing 40% HB flour required less work input than the corresponding 20% blend noodles due to a higher water absorption at the elevated level of HB flour addition, which probably caused them to soften. The addition of any HB flour at either level to the CPSW flour resulted in significantly decreased brightness (L*) and yellowness (b*), elevated redness (a*), concomitant with a significantly greater number of specks per unit area of noodle sheet compared with the control flour. The addition of 40% HB flour to YAN decreased cook time and cooking losses. Noodle firmness, as determined by maximum cutting stress (MCS), was significantly increased by the addition of 40% HB flour. Noodle chewiness, as determined by the texture profile analysis (TPA), was affected by the type of starch in the barley samples; the addition of waxy and ZAW HB flour decreased chewiness, whereas normal and HA HB flour increased chewiness of composite noodles.     

Significance of Amylose Content of Wheat Starch on Processing and Textural Properties of Instant Noodles

The effect of amylose content of starch on processing and textural properties of instant noodles was determined using waxy, partial waxy, and regular wheat flours and reconstituted flours with starches of various amylose content (3.0–26.5). Optimum water absorption of instant noodle dough increased with the decrease of amylose content. Instant noodles prepared from waxy and reconstituted wheat flours with ≤12.4% amylose content exhibited thicker strands and higher free lipids content than wheat flours with ≥17.1% amylose content. Instant noodles of ≤12.4% amylose content of starch exhibited numerous bubbles on the surface and stuck together during frying. Lightness of instant noodles increased from 77.3 to 81.4 with the increase of amylose content of starch in reconstituted flours. Cooking time of instant noodles was 4.0–8.0 min in wheat flours and 6.0–12.0 min in reconstituted flours, and constantly increased with the increase in amylose content of starch. Hardness of cooked instant noodles positively correlated with amylose content of starch. Reconstituted flours with ≤12.4% amylose content of starch were higher in cohesiveness than those of wheat flours of wild‐type and partial waxy starches and reconstituted flours with ≥17.1% amylose content. Instant fried noodles prepared from double null partial waxy wheat flour exhibited shorter cooking time, softer texture, and higher fat absorption (1.2%) but similar color and appearance compared with noodles prepared from wheat flour of wild‐type starch.     

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.     

End Use Quality of Waxy Wheat Flour in Various Grain‐Based Foods

The practical applications of flour from waxy (amylose‐free) hexaploid wheat (Triticum aestivum L.) were assessed. The applications evaluated were bread, cakes, white salted noodles, and pasta for gyoza. An excessive addition of waxy hexaploid wheat flour to total wheat flour (>20%) resulted in poorer functional properties (sticky, lumpy, or less crispy textures) in almost every end use product. However, incorporation of <20% waxy hexaploid wheat flour, produced considerable improvement in shelf‐life characteristics. After one day of storage, the bread from flour including waxy hexaploid wheat flour maintained moistness, softness, and stickiness. This application of waxy hexaploid wheat flour as an antistaling ingredient was also confirmed in cake products. Tests were also conducted on alimentary pasta products. In alimentary pasta, waxy hexaploid wheat flour was most effective when utilized for frozen fried dumplings (gyoza). By using flour including 30 or 50% waxy hexaploid wheat flour, the problem of firmness was solved without other ingredients. In conclusion, flour from waxy hexaploid wheat may be useful in developing more increased staling‐ and freezing‐tolerant grain‐based foods. Starch properties could be responsible for these improved characteristics.     

Rheological Properties of Starch Gels from Wheat Mutants with Reduced Amylose Content

Wheat lines with reduced amylose content were recently produced by single and double mutation from a low‐amylose line, Kanto 107. They are appropriate for clarifying the influence of amylose content on starch gel properties because of their similar genetic background. When measured using the concanavalin A method (ConA), the total amylose content of isolated starches from Kanto 107 and three mutants (K107Afpp4, Tanikei A6599‐4, K107Wx2) was 24.8, 18.5, 7.1, and 1.7%, respectively. Results of differential scanning calorimetry (DSC) showed that the difference in amylose content strongly affected gelatinization conclusion temperature and enthalpy. We prepared 30 and 40% starch gels and measured their dynamic shear viscoelasticity using a rheometer with parallel plate geometry. Compressive and creep‐recovery tests were conducted under uniaxial compression. The storage shear modulus correlated highly with the amylose content of starch in 30 and 40% starch gels. The creep‐recovery test showed a clear distinction in creep curves among starch samples. When the compressive force required for 50, 80, and 95% strains was compared, starch gels with lower amylose content showed lower compressive force at 50% strain. Waxy starch gel (K107Wx2) showed higher compressive force at strain >80% than other samples due to its sticky property.     

Functional Characteristics of Bread Wheat (Triticum aestivum L.) Near‐Isogenic Lines Differing at the Waxy (Wx) Locus

The Waxy (Wx) gene in hexaploid wheat (Triticum aestivum L.) encodes granule‐bound starch synthase (GBSS1), which is involved in the synthesis of amylose, a mostly linear glucan polymer that makes up ∼25% of wheat starch. A null mutation of the Wx gene in each of the three genomes is associated with starch almost entirely consisting of the branched glucan polymer amylopectin (waxy starch), with corresponding changes in functionality. However, the rheological behavior of partially waxy starch remains unclear. The objective of this study was to characterize flour and baking quality in 16 near‐isogenic lines, null at the Wx locus on zero, one, two, or all three genomes, grown in four different environments. Across allelic groups, significant variations in amylose concentrations, flour paste viscosity, loaf structure and texture, dough stability, and proximate variables were observed. Because waxy wheat starch has greater water absorbance and resistance to retrogradation than normal starch, its inclusion in flour blends has been suggested as a means of improving the texture and appearance of bakery products and noodles. The results indicate that wheat encoding <3 functional homeologs of GBSS1 produces starch that has potential in the production of certain food items, such as Asian noodles. However, further research is necessary to determine the optimal amylose‐to‐amylopectin ratio to improve baking quality.     

Effects of Starch Amylose Content of Wheat on Textural Properties of White Salted Noodles

White salted noodles were prepared through reconstitution of fractionated flour components with blends of waxy and regular wheat starches to determine the effects of amylose content on textural properties of white salted noodles without interference of protein variation. As the proportion of waxy wheat starch increased from 0 to 52% in starch blends, there were increases in peak viscosity from 210 to 640 BU and decreases in peak temperature from 95.5 to 70.0°C. Water retention capacity of waxy wheat starches (80–81%) was much higher than that of regular wheat starch (55–62%). As the waxy wheat starch ratio increased in the starch blends, there were consistent decreases in hardness of cooked noodles prepared from reconstituted flours, no changes in springiness and increases in cohesiveness. White salted noodles produced from blends of regular and waxy wheat flours became softer as the proportion of waxy wheat flour increased, even when protein content of flour blends increased. Amylose content of starch correlated positively with hardness and negatively with cohesiveness of cooked white salted noodles. Protein content of flour blends correlated negatively with hardness of cooked noodles, which were prepared from blends of regular (10.5% protein) and waxy wheat flours (> 16.4% protein).     

Significance of Starch Properties and Quantity on Sponge Cake Volume

We evaluated the qualitative and quantitative effects of wheat starch on sponge cake (SC) baking quality. Twenty wheat flours, including soft white and club wheat of normal, partial waxy, and waxy endosperm, as well as hard wheat, were tested for amylose content, pasting properties, and SC baking quality. Starches isolated from wheat flours of normal, single‐null partial waxy, double‐null partial waxy, and waxy endosperm were also tested for pasting properties and baked into SC. Double‐null partial waxy and waxy wheat flours produced SC with volume of 828–895 mL, whereas volume of SC baked from normal and single‐null partial waxy wheat flours ranged from 1,093 to 1,335 mL. The amylose content of soft white and club wheat flour was positively related to the volume of SC (r = 0.790, P < 0.001). Pasting temperature, peak viscosity, final viscosity, breakdown, and setback also showed significant relationships with SC volume. Normal and waxy starch blends having amylose contents of 25, 20, 15, and 10% produced SCs with volume of 1,570, 1,435, 1,385, and 1,185 mL, respectively. At least 70 g of starch or at least 75% starch in 100 g of starch–gluten blend in replacement of 100 g of wheat flour in the SC baking formula was needed to produce SC having the maximum volume potential. Starch properties including amylose content and pasting properties as well as proportion of starch evidently play significant roles in SC baking quality of wheat flour.     

Reduced Amylose Effects on Bread and White Salted Noodle Quality

Amylose content in wheat endosperm is controlled by three Wx loci, and the proportion of amylose decreases with successive accumulation of Wx null alleles at the three loci. The proportion of amylose is believed to influence end‐use quality of bread and Asian noodles. The objectives of this study were to determine influence of the allelic difference at Wx‐B1 locus on bread quality, bread firmness, and white salted noodle texture in a spring wheat cross segregating for the Wx‐B1 locus and in a set of advanced spring wheat breeding lines differing in allelic state at the Wx‐ B1 locus. In addition, we examined the relationship between amylose content and flour swelling properties on bread and noodle traits. Fifty‐four recombinant inbred lines of hard white spring wheat plus parents were grown in replicated trials in two years, and 31 cultivars and breeding lines of hard spring wheat were grown in two locations. Bread and white salted noodles were processed from these trials. The presence of the Wx‐B1 null allele reduced amylose content by 2.4% in a recombinant inbred population and 4.3% in a survey of advanced breeding lines and cultivars compared with the normal. The reduced amylose was accompanied by an average increase in flour swelling power (FSP) for the Wx‐B1 null group of 0.8 g/g for the cross progeny and 2.3 g/g for the cultivar survey group. The Wx‐B1 allelic difference did not affect flour protein in cross progeny where the allelic difference was not confounded with genetic background. Bread from the Wx‐B1 null groups on average had increased loaf volume and was softer than the normal group for the cross progeny and cultivar survey group. The Wx‐B1 allelic difference altered white salted noodle texture, most notably noodle springiness and cohesiveness where the Wx‐B1 null groups was more springy and more cohesive than the normal groups for both sets of genetic materials. Flour protein was more highly related to loaf volume than were FSP or amylose. Both flour protein and FSP were positively related to noodle textural traits, but especially noodle springiness and cohesiveness.     

Evaluation of White Salted Noodles Enriched with Oat Flour

Oat consumption is regarded as having significant health benefits. The enrichment of white salted noodles with oat flour would provide a potential health benefit but may affect the texture and sensory quality. Oat cultivars grown in Western Australia (Yallara, Kojonup, Mitika, Carrolup, and new line SV97181‐8) and a commercial oat variety were milled into flour and added to wheat flour at 10, 20, and 30% to produce oat‐enriched white salted noodles. The purpose of the study was to determine the quality characteristics of the oat flours and to assess the influence the oat flour blends had on noodle texture, color, and sensory characteristics. In addition, another goal was to determine whether the different oat cultivars had similar potential to provide health benefits by measuring the β‐glucan content before and after processing. The results indicated that protein, ash content, and noodle firmness increased with the increased percentage of oat flour in the noodle formulations, whereas the pasting properties of the noodle wheat–oat flour blends did not differ significantly. The color of raw noodle sheets and boiled noodles changed significantly with oat incorporation and resulted in lower lightness/brightness, higher redness, lower yellowness, and lower color stability in comparison to standard wheat white salted noodles. Noodles made with the lowest oat percentage (10%) scored highest for all sensory parameters and were significantly different in appearance, color, and overall acceptability compared with noodles made with 20 and 30% oat flour. The β‐glucan content of the flour blends increased with the increase in the level of oat incorporation but subsequently decreased during processing into noodles. The decrease in the β‐glucan content varied across the different oat cultivars and levels of incorporation into the noodles. A new oat cultivar, SV97181‐8, exhibited the least β‐glucan loss during processing. In this study, the quality characteristics of white salted noodles enriched with oat flour from Western Australian cultivars were determined to provide essential information for the commercial development of healthier noodles.     

Physicochemical and Structural Characteristics of Flours and Starches from Waxy and Nonwaxy Wheats

A waxy spring wheat (Triticum aestivum L.) genotype was fractionated into flour and starch by roller and wet‐milling, respectively. The resultant flour and starch were evaluated for end‐use properties and compared with their counterparts from hard and soft wheats and with commercial waxy and nonwaxy corn (Zea mays L.) starches. The waxy wheat flour had exceptionally high levels of water absorption and peak viscosity compared with hard or soft wheat flour. The flour formed an intermediate‐strength dough that developed rapidly and was relatively susceptible to mixing. Analysis by differential scanning calorimetry and X‐ray diffractometry showed waxy wheat starch had higher gelatinization temperatures, a greater degree of crystallization, and an absence of an amylose‐lipid complex compared with nonwaxy wheat. Waxy wheat and corn starches showed greater refrigeration and freeze‐thaw stabilities than did nonwaxy starches as demonstrated by syneresis tests. They were also similar in pasting properties, but waxy wheat starch required lower temperature and enthalpy to gelatinize. The results show analogies between waxy wheat and waxy corn starches, but waxy wheat flour was distinct from hard or soft wheat flour in pasting and mixing properties.     

Associations of Starch Gel Hardness,Granule Size,Waxy Allelic Expression,Thermal Pasting,Milling Quality,and Kernel Texture of 12 Soft Wheat Cultivars

Starches were isolated from 12 soft wheat (Triticum aestivum L.) cultivars and were characterized for waxy (Wx) allelic expression, thermal pasting characteristics, and starch granule size. Gels were produced from the thermally degraded starches and were evaluated using large deformation rheological measurements. Data were compared with cultivar kernel texture, milling characteristics, starch chemical analyses, and flour pasting characteristics. Larger flour yields were produced from cultivars that had larger starch granules. Flour yield also was correlated with lower amylose content and greater starch content. Harder starch gels were correlated with higher levels of amylose content and softer kernel texture. The cultivar Fillmore, which had a partial waxy mutation at the B locus, produced the highest peak pasting viscosity and the lowest gel hardness. Softer textured wheats had greater lipid‐complexed amylose and starch phosphorus contents and had less total starch content. Among these wheats of the soft market class, softer textured wheats had larger starch granules and harder textured wheats had smaller starch granules. In part, this may explain why soft wheats vary in texture. The smaller granules have larger surface area available for noncovalent bonding with the endosperm protein matrix and they also may pack more efficiently, producing harder endosperm.     

The Impact of Oat Quality on White Salted Noodles Containing Oat Flour

This research compared the physicochemical properties of six milling oat cultivars from Western Australia over two growing seasons (2011 and 2012). Variations among the cultivars in physicochemical properties, particularly β‐glucan content, were assessed to determine their suitability for incorporation into white salted noodles at a level of 30% of the flour component. The average across six oat cultivars grown in 2012 was significantly higher (P < 0.05) for protein content, lipid content, and volume of smaller sized particles (<100 µm) and significantly lower for ash content, starch damage, and volume of larger particles (>100 µm) in comparison with the average across the same oat cultivars grown in 2011. The year of cultivation by cultivar interaction was significant (P < 0.05) for ash content, protein content, β‐glucan content, starch damage, and particle size. Oat cultivar Mitika had the highest peak viscosity for 100% oat flour (whole groat) and 30% oat–wheat (OW) flour blend, which may be owing to lower amylose percentage, high protein content, and greater volume of smaller particles. The effect of growing season had greater impact on OW noodle firmness than the genetic effect of cultivars. The eating and cooking quality attributes of OW noodles, such as color, color stability, firmness, and cooking solid loss were superior for those incorporated with 2012 oat flour (whole groat) compared with 2011 oat flour. Among the six oat cultivars, Williams produced noodles with poor cooking and eating quality, and Mitika was easier to handle during processing and produced noodles with superior brightness and color stability in comparison with other oat cultivars evaluated.     

Sources of Variation for Starch Gelatinization,Pasting, and Gelation Properties in Wheat

The starch of wheat (Triticum aestivum L.) flour affects food product quality due to the temperature-dependent interactions of starch with water during gelatinization, pasting, and gelation. The objective of this study was to determine the fundamental basis of variation in gelatinization, pasting, and gelation of prime starch derived from seven different wheat cultivars: Kanto 107, which is a partial waxy mutant line, and six near-isogenic lines (NILs) differing in hardness. Complete pasting curves with extended 16-min hold at 93°C were obtained using the Rapid Visco Analyser (RVA). Apparent amylose content ranged from 17.5 to 23.5%; total amylose content ranged from 22.8 to 28.2%. Starches exhibited significant variation in onset of gelatinization. However, none of the parameters measured consistently correlated with onset or other RVA curve parameters that preceded peak paste viscosity. Peak paste viscosity varied from 190 to 323 RVA units (RVU). Higher peak, greater breakdown, lower final viscosity, negative setback, and less total setback were associated with lower apparent and total amylose contents. Each 1% reduction in apparent or total amylose content corresponded to an increase in peak viscosity of about 22 and 25 RVU, respectively, at 12% starch concentration. Of the seven U.S. cultivars, the lower amylose cultivars Penawawa and Klasic were missing the granule-bound starch synthase (GBSS; ADPglucose starch glycosyl transferase, EC 2.4.4.21) protein associated with the Waxy gene locus on chromosome 4A (Wx-B1 locus). Kanto 107 was confirmed as missing both the 7A and 4A waxy proteins (Wx-A1 and Wx-B1 loci). The hardness NIL also were shown to be null at the 4A locus. Apparent and total amylose contents of prime starch generally corresponded well to the number of GBSS proteins; although the hardness NIL tended to have somewhat higher amylose contents than did the other GBSS 4A nulls. We concluded that reduced quantity of starch amylose due to decreased GBSS profoundly affects starch gelatinization, pasting, and gelation properties.     

Production of Bihon-type Noodles from Maize Starch Differing in Amylose Content

Maize starches extracted from selected maize cultivars with 0.2–60.8% amylose contents were used to produce bihon-type noodles. Starch dough using a pregelatinized starch binder was prepared and extruded through a laboratory-scale extruder simulating the traditional process of making bihon in the Philippines. The normal maize starches with amylose content of ≈28% were successfully used for bihon-type noodle production, but waxy maize starches with 0.2–3.8% amylose content and high-amylose maize starches with 40.0–60.8% amylose content failed to produce bihon-type noodles. Viscoamylograph profile parameters and swelling volume are significantly correlated to amylose content of maize starch samples evaluated. These physicochemical properties may be used to indicate that the starch samples at normal amylose levels may be used for bihon-type noodles. Starch noodles produced in the laboratory were not significantly different in terms of either cooking quality or textural properties from two commercially produced maize noodle samples, except for adhesiveness. The laboratory process and fabricated extruder can be used to produce bihon-type noodles.     

Impact of Genotype and Environment on the Quality of Amber Durum Wheat Alkaline Noodles

Canada Western Amber Durum wheat cultivars (4), Canada Western Red Spring (1), and Canada Western Hard White Spring (1) wheat were grown at three sites in 2007 to evaluate the effect of genotype (G) and environment (E) on the quality of yellow alkaline noodles (YAN). YAN were evaluated for color, appearance, and cooked texture. Brightness (L*) and yellowness (b*) of YAN made from durum cultivars were significantly higher than common wheat. Durum flour yellow pigment content was approximately fourfold greater than common wheat while noodle speckiness was approximately half of CWRS at 2 hr with environment accounting for >75% of the variance for each parameter. Resistance to compression (RTC) and recovery (REC) of cooked durum alkaline noodles were equivalent or superior to common wheat noodles even when lower grade durum wheat flour was used. In conclusion, cooked durum noodle texture parameters were all significantly influenced by genotype and environment, with environment accounting for 66–71% of their variance.