Comparison of Physicochemical Properties and Structures of Sugary‐2 Cornstarch with Normal and Waxy Cultivars

Starches from normal, waxy, and sugary‐2 (su2) corn kernels were isolated, and their structures and properties determined. The total lipid contents of normal, waxy, and su2 corn starches were 0.84, 0.00, and 1.61%, respectively. Scanning electron micrographs showed that normal and waxy corn starch granules were spherical or angular in shape with smooth surfaces. The su2 starch granules consisted of lobes that resembled starch mutants deficient in soluble starch synthases. Normal and waxy corn starches displayed A‐type X‐ray patterns. The su2 starch showed a weak A‐type pattern. The chain‐length distributions of normal, waxy, and su2 debranched amylopectins showed the first peak chain length at DP (degree of polymerization) 13, 14, and 13, respectively; second peak chain length at DP 45, 49, and 49, respectively; and highest detectable DP of 80, 72, and 76, respectively. The su2 amylopectin showed a higher percentage of chains with DP 6–12 (22.2%) than normal (15.0%) and waxy (14.6%) amylopectins. The absolute amylose content of normal, waxy, and su2 starches was 18.8, 0.0, and 27.3%, respectively. Gel‐permeation profiles of su2 corn starch displayed a considerable amount of intermediate components. The su2 corn starch displayed lower gelatinization temperature, enthalpy change, and viscosity; a significantly higher enthalpy change for melting of amylose‐lipid complex; and lower melting temperature and enthalpy change for retrograded starch than did normal and waxy corn starches. The initial rate of hydrolysis (3 hr) of the corn starches followed the order su2 > waxy > normal corn. Waxy and su2 starches were hydrolyzed to the same extent, which was higher than normal starch after a 72‐hr hydrolysis period.     

Amylopectin Staling of Cooked Milled Rices and Properties of Amylopectin and Amylose

Starches of waxy rices that showed varietal differences in hardness testing of cooked rice after amylopectin staling and high-amylose content (AC) rices differing in gel consistency (GC) and starch gelatinization temperature (GT) were studied to determine the factors related to varietal differences in amylopectin staling of cooked rice. Intermediate- and high-GT starches showed greater amylopectin staling of gelatinized rice by hardness testing values or differential scanning calorimetry (DSC) endotherm than did low-GT starches in both waxy and nonwaxy rices. Isoamylase-debranched amylopectins of waxy rices differed in the ratio of weight-average degree of polymerization (DP_w) fractions, but these fraction ratios were not simply related to differences in amylopectin staling of cooked rice. Among high-AC rices, amylopectin from low-GT starch was confirmed to have higher iodine affinity (2.3–2.5%) than amylopectin from intermediate-GT starches (1.7–1.8%), regardless of GC. Within high-AC starch of the same GT type, soft-GC rice corresponded with more A + B₁ DP_w 16–18 and less B₃ DP_w 150–200 fractions of debranched amylopectin and low DP_w of amylose. Amylopectin of amylose extender mutant of IR36 was confirmed to have a longer chain length than ordinary rice amylopectin: the debranched amylopectin has more B₂ DP_w 47–51 fraction, less A + B₁ DP_w fraction, but no B₄ fraction with DP_w > 200. Only high-AC amylopectin had debranched fraction with DP_w >120.     

Molecular Size Distribution and Amylase Resistance of Maize Starch Nanoparticles Prepared by Acid Hydrolysis

The molecular size distribution of maize starch nanoparticles (SNP) prepared by acid hydrolysis (3.16M H₂SO₄) and their amylase‐resistant counterparts, before and after debranching, was investigated. The weight average molecular weight (M_w) and linear chain length distribution were determined by high‐performance size‐exclusion chromatography (HPSEC) and high‐performance anion‐exchange chromatography (HPAEC), respectively. The objective was to understand the role of amylose involvement in the formation of SNP showing different crystalline structures (A‐ and B‐types). The HPSEC profiles of SNP before debranching from waxy, normal, and high‐amylose maize starches showed broad monomodal peaks. Debranched SNP from waxy maize eluted in a single narrow peak, whereas those from nonwaxy starches showed a multimodal distribution. Similar trends were also observed for the chain length distribution patterns, for which the longest detectable chains (degree of polymerization [DP] 31) in waxy maize were significantly lower than those of nonwaxy maize starches (DP 55–59). This indicated the potential amylose involvement in the SNP structure of normal and high‐amylose starches. Further evidence of amylose involvement was ascribed to the resistance of SNP toward amylolysis (Hylon VII > Hylon V > normal > waxy). The amylase‐resistant residues of SNP from high‐amylose maize starches were composed of both low M_w linear and branched chains.     

Structural Properties of Starch Fractions Isolated from Normal and Mutant Corn Genotypes Using Different Methods

The objectives of this research study were to isolate, evaluate, and compare the fine structures of starch fractions obtained from a wild‐type (normal) corn starch and amylose‐extender25, dull39, sugary2, and sugary1 corn mutants in the same genetic background using three different fractionation procedures based on gel‐permeation chromatography or alcohol‐precipitation methods. Starch fractions obtained from each of the three methods were enzymatically debranched and analyzed using high‐performance anion‐exchange chromatography with a postcolumn amyloglucosidase reactor and a pulsed amperometric detector. The separations were performed by fractionation on a GPC column, by precipitation with 1‐butanol, and by preferential precipitation with 1‐butanol and isoamyl alcohol. Using any of these methods, no apparent differences in the molecular weight distributions of amylopectin or of amylose among the different starches were observed. The proportions of branch chain lengths of the starch components obtained by the various fractionation methods were very similar among methods for each of the starch types analyzed, such as the predominance of long branch chains in ae25 corn and that of the short branch chains in su2 corn. Overall, the effect of the corn mutations was more important to the differences observed among the starch types than was the method of fractionation used.     

Effects of Amylopectin Branch Chain Length and Amylose Content on the Gelatinization and Pasting Properties of Starch

Structures and properties of starches isolated from different botanical sources were investigated. Apparent and absolute amylose contents of starches were determined by measuring the iodine affinity of defatted whole starch and of fractionated and purified amylopectin. Branch chain-length distributions of amylopectins were analyzed quantitatively using a high-performance anion-exchange chromatography system equipped with a postcolumn enzyme reactor and a pulsed amperometric detector. Thermal and pasting properties were measured using differential scanning calorimetry and a rapid viscoanalyzer, respectively. Absolute amylose contents of most of the starches studied were lower than their apparent amylose contents. This difference correlated with the number of very long branch chains of amylopectin. Studies of amylopectin structures showed that each starch had a distinct branch chain-length distribution profile. Average degrees of polymerization (dp) of amylopectin branch chain length ranged from 18.8 for waxy rice to 30.7 for high-amylose maize VII. Compared with X-ray A-type starches, B-type starches had longer chains. A shoulder of dp 18–21 (chain length of 6.3–7.4 nm) was found in many starches; the chain length of 6.3–7.4 nm was in the proximity of the length of the amylopectin crystalline region. Starches with short average amylopectin branch chain lengths (e.g., waxy rice and sweet rice starch), with large proportions of short branch chains (dp 11–16) relative to the shoulder of dp 18–21 (e.g., wheat and barley starch), and with high starch phosphate monoester content (e.g., potato starch) displayed low gelatinization temperatures. Amylose contents and amylopectin branch chain-length distributions predominantly affected the pasting properties of starch.     

Thermal Decomposition of Corn Starch with Different Amylose/Amylopectin Ratios in Open and Sealed Systems

Thermal decomposition of corn starches with different amylose to amylopectin ratios (0:100 waxy, 23:77 maize, 50:50 Gelose 50, 80:20 Gelose 80) were studied by thermogravimetric analysis (TGA) in an open system and differential scanning calorimetry (DSC) in a sealed system using stainless steel high‐pressure pans with varying water content (9–75%). The initial water content did not affect the decomposition temperature in the open system because all water evaporated from samples before reaching the decomposition temperature. The sequence of decomposition temperature of different starches is waxy > maize > G50 > G80 in an open system. The moisture content in starch remains constant during the degradation process in a sealed system. Two decomposition temperatures were observed in the sealed system: the first at lower temperature represents long chain scission and the second at higher temperature involves decomposition of the glucose ring. The sequence of the first degradation is waxy > maize > G50 > G80. There is no observable difference of the second degradation for the samples containing different amylose to amylopectin ratios. The higher the moisture content, the lower the second decomposition temperature. Decomposition of glucose was used to confirm the mechanisms proposed for the starch degradation.     

Starch Characteristics of the Rice Mutant du2‐2 Taichung 65 Highly Affected by Environmental Temperatures During Seed Development

The effects of environmental temperature (21 vs. 28°C) during rice seed development on the starch characteristics (apparent amylose content, amylopectin chain length distribution, and gelatinization properties) of nonwaxy Taichung 65 (T65), waxy Taichung (T65wx), du2‐2 mutated low‐amylose strain Taichung (76‐3/T65), and Koshihikari were studied. Amylose contents increased with decreasing environmental temperatures. Analysis of the amylopectin chain length distribution showed that the relative amounts of long chains with degree of polymerization (DP) > 25 in all starches decreased if maturation occurred at 21°C. Gelatinization onset, peak, and conclusion temperatures and enthalpies decreased with decreasing environmental temperatures. Of all starches studied, the du2‐2 mutated low‐amylose Taichung (76‐3/T65) was most affected by maturation temperatures. These results indicate that the du2‐2 mutated low‐amylose Taichung (76‐3/T65) may be a useful strain in understanding biochemical and genetic starch biosynthesis response to slight changes in temperature.     

Structures and physicochemical properties of six wild rice starches

Starches from six wild rice cultivars were studied for their chemical structures and physicochemical properties and compared with a long-grain rice starch. The six wild rice starches were similar in morphological appearance, X-ray diffraction patterns, swelling power, and water solubility index but different in amylose content, beta-amylolysis limit, branch chain length distribution, thermal properties, and pasting properties. The structure of the wild rice amylopectins was close to that of waxy rice amylopectin with more branching and a larger proportion of short branch chains of degree of polymerization 6-12 as compared with that of amylopectin from rice starch with a similar amylose content. The differences in branch chain length distribution of amylopectin and amylose content were assumed to contribute to the differences in physicochemical properties among the six wild rice starches as well as to the differences between the wild rice starches and the rice starch.     

Molecular Characterization of Corn Starch Using an Aqueous HPSEC‐MALLS‐RI System Under Various Dissolution and Analytical Conditions

Molecular characteristics based on absolute weight‐average molecular weight (M_w) and z‐average radius of gyration (R_g) of normal corn starch were analyzed by high‐performance size‐exclusion chromatography (HPSEC) attached to multiangle laser‐light scattering (MALLS) and refractive index (RI) detectors under different starch dissolution and analytical conditions. Autoclaving (121°C, 20 min) or microwave heating (35 sec) provided better HPSEC recovery and higher M_w for starch molecules than simple dissolution in hot water. The M_w for the autoclaved corn amylopectin and amylose fractions separated with a TSK G5,000 column at 60°C were 201 × 10⁶ and 3.3 × 10⁶, respectively. The specific volume for gyration (SV_g) calculated from M_w and R_g could be used for the comparison of molecular compactness which was inversely related to the degree of branching. The SV_g values of amylopectin and amylose fractions in the chromatogram (TSK G5,000, autoclaved for 20 min) were 0.092 and 0.529, respectively. But a portion (20–30%) of large amylopectin molecules did not pass the injection membrane filter (3.0 μm) and the SEC column, resulting in incomplete recovery. The unfiltered portion varied according to the dissolution treatment. Homogenization (7,000 rpm, 5 or 10 min) of the starch solution improved the recovery of the amylopectin fraction, but significantly increased the M_w of the amylose fraction (17 × 10⁶). Sonication for 5 min degraded starch molecules. For accurate analysis of a native starch using an aqueous SEC, the starch should be fully dissolved with proper treatment such as autoclaving or microwaving, and the column should be improved for full recovery of large amylopectin molecules.     

Fine Structures of Amylose and Amylopectin from Large,Medium, and Small Waxy Barley Starch Granules

Amylose and amylopectin were prepared from large, medium, and small granule starches of classified waxy barley flour, and their fine structures were investigated. The amylose content had a wide distribution range (≈1.4–9.4%). Number‐average degrees of polymerization (DP_n) of the amyloses were similar among the samples (≈1,200–1,300). But number of chains per molecule (NC) decreased from the surface to the center (≈6–10 chains). DP_n of the amylopectins varied from 4,657 to 14,604; decreased in the order of large, medium, and small granules in same fractions of the grain; and increased from the surface layer to the center. Longest chains (LC) were not found in any of the amylopectin molecules. The large amylopectin molecule had more long chains and fewer A chains than the small molecule. The amylose content had definite effects on the transition temperature range and crystal formation of the starch granules. There were positive correlations between DP_n of the amylopectin and relative crystallinity (γ = +0.69) and enthalpy value (γ = +0.80), respectively. These findings may help to elucidate biosynthesis mechanism of starch.     

Structure and functional properties of sorghum starches differing in amylose content

Starches were isolated from grains of waxy, heterowaxy, and normal sorghum. To study the relationship between starch structure and functionality and guide applications of these starches, amylose content, amylopectin chain-length distributions, gelatinization and retrogradation, pasting properties, dynamic rheological properties, and in vitro enzyme digestion of raw starches were analyzed. Heterowaxy sorghum starch had intermediate amylose content, pasting properties, and dynamic rheological properties. Stress relaxation was a useful indicator of cooked starch cohesiveness. Cooked heterowaxy sorghum starch (10% solids) had a viscoelastic-solid type of character, whereas cooked waxy sorghum starch behaved like a viscoelastic liquid. Amylopectin of normal sorghum starch had a slightly higher proportion of chains with degree of polymerization (DP) of 6-15 (45.5%) compared with amylopectin of heterowaxy starch (44.1%), which had a gelatinization peak temperature 2 degrees C higher than normal sorghum starch. Heterowaxy sorghum starch contained significantly lower rapidly digestible starch (RDS) and higher resistant starch (RS) than waxy sorghum starch.     

Molecular Structure and Some Physicochemical Properties of High‐Amylose Barley Starches

The molecular structure and some physicochemical properties of starches from two high‐amylose cultivars of barley, high‐amylose Glacier A (HAG‐A) and N (HAG‐N), were examined and compared with those of a normal cultivar, Normal Glacier (NG). The true amylose contents of HAG‐A, HAG‐N, and NG were 41.0, 33.4, and 23.0%, respectively. Iodine affinities before and after defatting of starch, and thermograms of differential scanning calorimetry, indicated that HAG‐A and HAG‐N starches had a higher proportion of amylose‐lipid complex than did NG starch. The amylopectins from HAG‐A and HAG‐N were similar to NG amylopectin in average chain length (18–19), β‐amylolysis limit (β‐AL 56–57%), number‐average degrees of polymerization (DP_n 6,000–7,500) and chain length distribution. Very long chains (1–2%) were found in amylopectins from all cultivars. HAG‐A amylopectin had a larger amount of phosphorus (214 ppm) than the others. The amyloses from HAG‐A and HAG‐N resembled NG amylose in DP_n (950–1,080) and β‐AL (70–74%). However, HAG‐A and HAG‐N had a larger number of chains per molecule (NC 2.4–2.7) than NG amylose (1.8) and contained the branched amylose with a higher NC (9.5–10.6) than that of NG amylose (5.8), although molar fractions of the branched amylose (15–20%) were similar.     

Solubilization Effects on Molecular Weights of Amylose and Amylopectins of Normal Maize and Barley Starches

Structural characteristics of starches have been important to determine their physicochemical and functional properties. Solubilization procedures were tested to find a higher solubilization percentage and thereafter to study the structural characteristics of amylose and amylopectin. Size‐exclusion chromatography with refractive index (SEC‐RI) system using a pullulan standard curve was tested to study the amylose molar mass. Also, a microbatch system using a MALLS detector was used to determine the molar mass and gyration radius of starch and amylopectin. Microwave heating produced higher solubility percentages than autoclaving, and there was a difference between both starches. The sample solubilized with microwave heating presented higher molar mass and gyration radius values than autoclave samples, showing that this process for structural studies provided information representative of the initial starch sample. When starch components were separated, amylose showed lower purity than amylopectin. Lower purity was obtained for amylose separated from barley starch, but no difference was obtained for purity of amylopectin separated from both starches. Barley amylopectin had a higher solubility percentage than maize amylopectin. Molar mass of barley amylose was 1.03 × 10⁵ g/mol and for maize of 2.25 × 10⁵ g/mol. Molar mass values of amylopectin separated from both starches were lower than the starch counterparts, although the same solubilization procedure (microwave heating) was used. The difference might be due to depolymerization during separation of starch components.     

Molecular degradation rate of rice and corn starches during acid-methanol treatment and its relation to the molecular structure of starch

The degradation rates of rice and corn starches with different contents of amylose treated in methanol containing 0.36% HCl at 25 degrees C for 1-15 days were evaluated by monitoring the weight average degree of polymerization of starch. A two-stage degradation pattern during acid-methanol treatment was found for the starches studied, which were the slow (first) and the rapid (second) degradation stages. Waxy starches showed a shorter time period of the first stage than that of nonwaxy starch. Rice starch showed a shorter time period of the first stage and a higher degradation rate of the second stage than the counterpart corn starch with similar amylose content. Despite the botanic source and amylose content of starch, the degradation rate of starch in the second stage significantly (p < 0.05) correlated to the S/L ratio (r = -0.886) and polydispersity (r = 0.859) of amylopectin branch chains of native starch.     

Fractionation of High-Amylose Maize Starches by Differential Alcohol Precipitation and Chromatography of the Fractions

Three high-amylose maize starches (HAS) and a common corn starch (CCS) were subjected to differential alcohol precipitation using isoamyl alcohol and 1-butanol to obtain fractions designated as amylose (AM), amylopectin (AP), and intermediate material (IM). For each starch, IM had a blue value and an iodine binding wavelength maximum (λ_max) between the λ_max of the respective AM and AP. Size-exclusion chromatography (SEC) showed similarities in the AM from CCS and HAS. HAS AP had higher blue values and iodine binding λ_max values than CCS AP. SEC of the intact HAS AP and IM both showed large proportions of material eluting after the void volume (45–85%) when compared to CCS AP and IM. Chain length (CL) distributions of debranched AP and IM indicated that these fractions from each starch were highly branched, and that AP had a shorter average chain length than IM. Consequently, the differential precipitation behavior of the HAS AP and IM appears dependent on general branching structure rather than size. We conclude that in both CCS and HAS, AP and IM are subsets of the branched molecules with AP as the predominant fraction. For HAS, AP and IM include molecules of a size typical for AM and contain a higher proportion of chains that are longer than those of CCS AP. Differential alcohol precipitation is a useful method of separating amylose, amylopectin, and intermediate material from HAS.     

Preparation and Properties of Starch Phosphates Using Waxy,Common, and High‐Amylose Corn Starches. I. Oven‐Heating Method

The structure and physicochemical properties of waxy, common, and high‐amylose corn starch phosphates prepared by oven heating were studied. Starch phosphates prepared by either slurry or dry‐mixing treatment before oven heating were also compared. The slurry treatment more efficiently incorporated phosphorus into starch relative to the dry‐mixing treatment under the reaction conditions studied. In general, the phosphorylated starch prepared by the slurry treatment exhibited a lower gelatinization temperature, a higher peak viscosity, a lesser degree of retrogradation, and improved freeze‐thaw stability compared with those prepared by the dry‐mixing treatment. Phosphorylation occurred probably in both amylose and amylopectin, and the amount and location of incorporated phosphate groups varied with starch types likely due to their different amylose and amylopectin contents. Waxy starch was more prone to phosphorylation, followed by common and high‐amylose starches, respectively.     

Effects of Granular Structures on the Pasting Behaviors of Starches

Japonica (Tainung 67 [TNu67]) and waxy (Taichung 70 [TCW70]) rice, normal and waxy corn, and cross-linked waxy rice and corn starches were used in an investigation of the influence of the granular structure on the pasting behavior of starch, using small amplitude oscillatory rheometry. Both normal corn and normal rice (TNu67) starches had the highest storage moduli (G′), followed by their cross-linked versions; native waxy corn and rice starches had the lowest. Native waxy starches showed paste characteristics (G′ < 500 Pa; tan δ > 0.2) at concentrations of up to 35%. However, cross-linked waxy starches exhibited gel behavior at 10% concentration (cross-linked TCW70) or higher (cross-linked waxy corn starch). The degrees of swelling power were in the order: TCW70 > native waxy corn > TNu67 ≅ cross-linked TCW70 ≅ normal corn ≅ cross-linked waxy corn starches. Solubilities were in the order: normal corn > TNu67 > native waxy > cross-linked waxy starches. The addition of 2% purified amylose from indica rice (Kaohsiung Sen 7) did not induce gelation of waxy corn starch. Swelling powers of normal corn, TNu67, and crosslinked waxy starches were similar, but normal corn and TNu67 had much higher G′ value. Such results implied that the formation of gel structure was governed by the rigidity of swollen granules and that the hot-water soluble component could strengthen the elasticity of the starch gel or paste.     

Barley grain constituents, starch composition, and structure affect starch in vitro enzymatic hydrolysis

The relationship between starch physical properties and enzymatic hydrolysis was determined using ten different hulless barley genotypes with variable carbohydrate composition. The ten barley genotypes included one normal starch (CDC McGwire), three increased amylose starches (SH99250, SH99073, and SB94893), and six waxy starches (CDC Alamo, CDC Fibar, CDC Candle, Waxy Betzes, CDC Rattan, and SB94912). Total starch concentration positively influenced thousand grain weight (TGW) (r(2) = 0.70, p < 0.05). Increase in grain protein concentration was not only related to total starch concentration (r(2) = -0.80, p < 0.01) but also affected enzymatic hydrolysis of pure starch (r(2) = -0.67, p < 0.01). However, an increase in amylopectin unit chain length between DP 12-18 (F-II) was detrimental to starch concentration (r(2) = 0.46, p < 0.01). Amylose concentration influenced granule size distribution with increased amylose genotypes showing highly reduced volume percentage of very small C-granules (<5 μm diameter) and significantly increased (r(2) = 0.83, p < 0.01) medium sized B granules (5-15 μm diameter). Amylose affected smaller (F-I) and larger (F-III) amylopectin chains in opposite ways. Increased amylose concentration positively influenced the F-III (DP 19-36) fraction of longer DP amylopectin chains (DP 19-36) which was associated with resistant starch (RS) in meal and pure starch samples. The rate of starch hydrolysis was high in pure starch samples as compared to meal samples. Enzymatic hydrolysis rate both in meal and pure starch samples followed the order waxy > normal > increased amylose. Rapidly digestible starch (RDS) increased with a decrease in amylose concentration. Atomic force microscopy (AFM) analysis revealed a higher polydispersity index of amylose in CDC McGwire and increased amylose genotypes which could contribute to their reduced enzymatic hydrolysis, compared to waxy starch genotypes. Increased β-glucan and dietary fiber concentration also reduced the enzymatic hydrolysis of meal samples. An average linkage cluster analysis dendrogram revealed that variation in amylose concentration significantly (p < 0.01) influenced resistant starch concentration in meal and pure starch samples. RS is also associated with B-type granules (5-15 μm) and the amylopectin F-III (19-36 DP) fraction. In conclusion, the results suggest that barley genotype SH99250 with less decrease in grain weight in comparison to that of other increased amylose genotypes (SH99073 and SH94893) could be a promising genotype to develop cultivars with increased amylose grain starch without compromising grain weight and yield.     

Characterization of Maize Starch Nanoparticles Prepared by Acid Hydrolysis

Starch nanoparticles (SNP) from maize starches of varying amylose content (0–71%) were prepared by acid hydrolysis (3.16M H₂SO_4, at 40°C up to 6 days) followed by repeated water washings. During the washing cycles, nonwaxy starches (normal, Hylon V, and Hylon VII) had suspended particles in the water washings, which were not evident in waxy starch. Microscopic examination revealed the presence of SNP in the “cloudy supernatants” of nonwaxy starches and in the “final washed residue” of waxy maize. The objective of this study was to collect SNP fractions accordingly and determine whether variation in the native starch amylose content would influence the yield, morphology, and crystallinity of the SNP. In nonwaxy starches, the yield of SNP increased up to 26.6% with hydrolysis time and was proportional to the amylose content. Morphology of SNP differed with starch type: flat/elliptical (500 nm) in waxy, oval/irregular (50–200 nm) in normal, oval/round (40–50 nm) in Hylon V, and square/polygonal (50–100 nm) in Hylon VII. X‐ray diffraction confirmed the presence of A‐type crystals in SNP from all starch types and a crystalline transformation from B‐ to A‐type in Hylon starches. The relative crystallinity of SNP was higher than their native starch counterparts.     

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.