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Summary: Making noodles based on broken rice (BR) is a green approach to promote the utilisation of rice byproducts (the underutilised bio‐materials with vast annual production). In this study, BR of Indica, Japonica and Glutinous varieties were semi‐dry milled to yield flour (BRI, BRJ and BRG). They were substituted for wheat flour at the level of 10% to prepare W‐BRI, W‐BRJ and W‐BRG noodles respectively. Among three varieties, BRG showed greatest whiteness, highest relative crystallinity and lowest pasting viscosities. Substitution of all BR flours decreased percentage of α‐helix but increased β‐sheet in fresh noodles. BRG substitution markedly enhanced the binding tightness of water to gluten or starch. Owing to the strongest swelling power and lowest pasting temperature (59.1 °C) of BRG, W‐BRG noodles showed shortest cooking time and highest cooking yield (190.64%). All noodles were sensorily acceptable, among which W‐BRG noodles had the greatest softness and least stickiness. W‐BRJ noodles presented more uniform and tightly packed microstructure, which might explain their lowest cooking loss (6.65%) and greater springiness. W‐BRI dough sheet had the most viscoelastic, and its noodles had the highest cohesiveness (0.65). Selective utilisation of rice variety is crucial for producing noodles with characteristic quality. [ABSTRACT FROM AUTHOR]

Comparative studies were conducted on physicochemical and technological properties of two black wheat (BW) varieties (cultivated in Shanxi Agricultural University) and their noodle‐making potential. Whole‐grain BW noodles showed acceptable cooking loss (≤10%) and strong antioxidant capacity. However, their textural quality remains to be enhanced. Regarding refined flour (RF) of the two BW varieties, Yunhei 14207 showed more anthocyanins, brighter color, and greater thermal stability (as reflected by the higher pasting temperature). 16W16 resulted in greater gluten content and better gluten quality of flour and higher dough stability, which contributed to the lower cooking loss and stronger tensile property of noodles. RF noodles of Yunhei 14207 displayed brighter appearance, although they had weaker tensile property. The stronger gluten network in noodles of 16W16 protected phenolics from release and degradation during drying, cooking, and steaming. Despite phenolics loss, RF noodles of Yunhei 14207 showed antioxidant capacity up to 14.97 mg TE/100 g. This research would promote understanding of characteristics of BW varieties. Considering the stronger gluten network of 16W16, its fortification in common wheat noodles at high proportion (>50%) may be promising to develop antioxidant noodles with further improved sensory quality. [ABSTRACT FROM AUTHOR]

Summary: This study explored the effects of adding A‐type starch (AS), B‐type wheat starch (BS) on the physicochemical or edible quality of dough sheet and noodle samples at different stages of the noodle‐making process, which included 1‐mixing, 2‐kneading, 3‐resting, 4‐sheeting and cutting and 5‐drying. The swelling power and pasting viscosities of samples in noodle‐making process were decreased compared with mixed flour, indicating gluten network during noodle‐making inhibits these properties of starch. Adding 20% BS enhanced the formation and aggregation of gluten network during kneading and drying compared by adding AS. The drying process increased cooking yield and cooking loss and decreased hardness and springiness, and the effect was weakened when adding BS. The correlation results show the increased solubility and decreased setback during drying are the main reason for the changes of cooking and texture quality of noodles. The increase of swelling power resulted in the increased cooking yield. [ABSTRACT FROM AUTHOR]

Buckwheat flour was extruded with different feeding moistures (FMs). It evaluated changes of dough, nutritional, and textural quality of noodles fortified with extruded buckwheat flour (EBF). Results indicated that EBF had significantly lower viscosities and was more resistant to retrogradation than control. EBF (30% FM) fortification remarkably prolonged composite dough stability time and reduced attenuation degree. Noticeable enhancement was observed in cooked noodles nutritional quality when EBF (18%~30% FM) fortification was employed. Compared with control, EBF (30% FM) fortification resulted in significantly higher content of total phenolics, total flavonoids, rutin, and kaempferol, as well as antioxidant capacity of cooked noodles. Furthermore, highest hardness, cohesion, springiness, and chewiness of noodles was achieved when fortified with EBF (30% FM), while the cooking loss was not reduced in contrast to control. Fortification with buckwheat flour extruded properly would improve both nutritional and texture quality of staple noodles. Practical applications: Recently, chronic diseases frequently occur in the world, and staple food prepared from only wheat could not cater for consumers' desire for health. Buckwheat contains abundant phenolics (especially flavonoids) that possess numerous bioactivities, such as antioxidant capacity. It is essential to investigate staple noodles based on wheat–buckwheat composite flour. Thermal processing could improve the bioactive phenolics level and antioxidant capacity of many cereal products (e.g., wheat, corn, and oat). Besides, it contributes to the desirable texture formation of staple foods by modifying the starch–gluten network, and could alter the processing property (e.g., flour viscosity). Therefore, it is worth considering the application of extrusion (a typical thermal processing technique) in staple industry. [ABSTRACT FROM AUTHOR]

Generally, heat‐moisture treatment (HMT) modified starch is prepared at atmospheric pressure without stirring, which is time‐consuming (8~24 hr) and uneven heating. The wheat flour (WF) and starch (WS) were modified by HMT in a high pressure reactor with a stirrer. Physicochemical properties of WF and WS after HMT for 30 min with different moisture and temperature conditions were investigated. Compared to native samples, decrease in peak viscosity, and increase in gelatinization temperature were found in both WF and WS after HMT treated at moisture of 25% and 30%. A decrease in rapidly digestible starch and slowly digestible starch content while an increase in resistant starch content was found for all moisture levels. By studying the effect of heat treatment on the digestibility of starch and flour, and the application of heat treatment in noodles, it provides a theoretical basis for the development of staple food products suitable for diabetic patients. Practical applications: Resistant starch (RS) within a calorie‐controlled diet is thought to be beneficial in protecting against metabolic syndrome and colon cancer. With the acceleration of the pace of life, a diet high in sugar and fat and a sedentary lifestyle, which can led to a rapid rise in the global incidence of diabetes. Therefore, reasonable diet is significant to stabilize and improve the condition of diabetic patients. Wheat flour provides the basis for breads and other baked products including noodles. Noodles are one of China's traditional staple foods. It is of great importance to explore and develop the noodle recipe suitable for the diabetic diet. Heat moisture treatment is an important physical treatment method used to improve the poor functional properties of native starch and is specially favorable for food applications. In this study, RS of wheat flour and starch was significantly increased during heat‐moisture treatment. By studying the effect of heat treatment on the digestibility of starch and flour, and the application of heat treatment in noodles, it provides a theoretical basis for the development of staple food products suitable for diabetic patients. [ABSTRACT FROM AUTHOR]

This research was aimed to investigate the influence of esterified starches on the quality and texture of fresh noodles by adding starches with different amylose contents (<1%, 23%, 50%, 80%). The application of pulsed electric fields (PEF) during esterification can improve the introduction of acetyl groups. The peak viscosity of esterified waxy starch was decreased obviously from 4,238 to 79 mPa s by PEF assistance. Compared to the conventional method, esterified starch with higher amylose content (>23%) by PEF assistance can improve the appearance and elasticity of its uncooked noodles, while the addition of waxy starch esters showed an opposite trend. The influence of PEF‐assisted modification on the increase in cooking yield and the decrease in hardness was more obvious compared to conventional method. Additionally, waxy starch esterified by the dual method exhibited a decrease in rapidly digestible starch content during in vitro digestion. Practical applications: This study was to explore the effects of esterification on maize starch with full range of amylose content as well as the modified starches applied on noodles. Conventional and PEF‐assisted dual methods have different influence on the rheological, cooking, and textural properties of noodles. Bright appearance and higher springiness, which were the desired properties of raw noodles for consumers, can be obtained by adding starch esters (except for waxy starch) modified by PEF‐assisted esterification rather than the conventional method. It can expand the application of PEF technology on flour products, especially for noodles. [ABSTRACT FROM AUTHOR]

Summary: Heat treatment and salt addition on the physicochemical properties and quality of fresh noodles were investigated. The water activity was decreased, while the bound water content was increased after heat treatment, and this effect was dependent on the treated intensity and salt concentration, which extended the shelf life of noodles. The content of SDS‐soluble protein was decreased after heat treatment, and this effect was dependent on the treated intensity. However, 3% salt concentration can reduce the aggregation of SDS‐soluble protein. The paste viscosities were reduced, whereas the gelatinisation temperatures increased after heat treatment, and the variation was increased with increasing salt concentration. The hardness and chewiness of cooked noodles were increased after heat treatment, but adding salt reduced this effect. Results showed the quality of heat‐treated noodles can be precisely controlled by the addition of salt, and the optimal treatment condition was 98 °C and 2% salt concentration. [ABSTRACT FROM AUTHOR]

Total starch (TS), large A‐type starch (AS), and small B‐type starch (BS) separated from wheat flour were used to be esterified with acetic anhydride via conventional and pulsed electric field‐assisted (PEF‐assisted) methods. The rheological properties of these esterified wheat starch and their effects on the quality of noodles were studied. The RVA results showed that the two esterification methods can reduce the peak viscosity of TS, AS, and increase that of BS and it was higher as modified by the PEF‐assisted method. While the loss factor of gel expressed the opposite trend. Gel hardness of all types of starch was greatly reduced by modification, especially for PEF‐assisted esterification. After adding modified starches to the noodle‐making flour, all the esterified starches can improve the color of noodles and increase the water absorption rate. Compared with noodles adding native BS, the stretching distance of noodles was added by 12 mm after being added PEF‐assisted esterified BS. Practical applications: This study explored the effects of esterification on total starch (TS), large size of A‐type starch (AS), and small size of B‐type starch (BS) as well as the modified starches applied on noodles. Adding pulsed electric field (PEF)‐assisted esterified starch was beneficial to improve the hardness of noodles and increase the stretching distance especially for that of adding PEF‐assisted BS. These results provide a technical reference that PEF‐assisted esterified starch, which can be considered as a food additive improver, has greater feasibility and effectiveness than conventionally esterified starch and it brings new light on the role of PEF technology in the texture and quality of cereal products. [ABSTRACT FROM AUTHOR]

Wheat flour was ground in an ultrafine pulveriser to obtain different levels of damaged starch ( DS). The effect of DS content on physicochemical properties of flour and quality attributes of Chinese noodles and northern-style Chinese steamed bread were investigated. Results showed that the degree of starch damage raised from 6.54% to 12.06% as grinding intensity increased from 0 to 130 Hz ( P < 0.05). The falling number, sedimentation value, starch pastes' viscosity, dough proofing stability were negatively, while water absorption, pastes thermal stability, the degree of starch pastes and dough level were positively correlated with DS content, respectively ( P < 0.05). The increase in DS content from 6.54% to 8.86% did not lead to a deterioration of texture characteristic, which might be attributed to the slight declining in hardness while enhancing in springiness and cohesiveness. The flour with DS content of 6.54-9.66% was suitable for steamed bread making. [ABSTRACT FROM AUTHOR]

• Moisture content first increased rapidly and then slowly during noodle cooking. • Large A-type wheat starch granules promoted the water uptake of cooked noodles. • Protein aggregation was earlier than starch gelatinization during noodle cooking. • Structural changes of starch and protein need good coordination during cooking. • Noodles with 50% B-type starch granules showed moderate firmness and resilience. The impact of the A/B-type wheat starch granule ratio on the rehydration behavior and cooking quality of noodles and the underlying mechanisms were investigated. The amounts of water absorbed increased sharply first and then slowly during cooking, and large A-type starch (AS) promoted the water absorption of noodles. The water penetrated gradually from the surface to the core, and noodles with a high ratio of AS or small B-type starch (BS) exhibited a more rapid water migration and faster structural changes at the initial stage and then became slower later. The protein appeared to react slightly earlier than starch during noodle cooking. Noodles with AS/BS ratio of 50:50 showed higher water absorption, good coordination between starch gelatinization rate and protein aggregation rate, and moderate firmness and resilience. A suitable AS/BS ratio and good coordination in structural transformations were needed to achieve a good quality cooked noodle. [ABSTRACT FROM AUTHOR]

In this study, three typical wheat cultivars (ZM366, AK58, and ZM103) with high, medium, and low gluten strength, respectively, were selected as the raw material. The starch granules separated from different stages of the noodle-making process, including kneading, resting, sheeting, cutting, and drying, were used to explore the structure, dynamic rheology, and quality of the noodles. The D50 (median diameter) of the starch granules decreased during the noodle-making process, and the reduction was enhanced by an increase in the gluten strength of the flour. Between steps 4 and 5 of the noodle-making process, the solubility of ZM103 variety increased from 4.3% to 5.0% at 80 °C, while the peak viscosity decreased from 3626 to 3386 mPa s, which resulted in a decrease in the cooking loss of noodles. Similar trend was observed in the ZM366 and AK58 varieties. The gelatinization enthalpy was reduced, suggesting that the crystalline regions of the starch granules were destroyed during the kneading process. Between steps 4 and 5 of the noodle-making process, the elastic modulus of the starch granules significantly increased, while the temperature at which maximum elastic modulus was decreased, indicating an increase in the crystalline stability of starch during the drying process. Correlation analysis indicated that the changes occurred to the gelatinization property was primarily due to the change in the particle size. Image 1 • Peak viscosity of starch was decreased gradually during noodle-making process. • The increased smaller starch granules would decrease its thermal stability. • Higher damaged starch content was produced in kneading and cutting steps. • Cooking loss of noodles was improved by the increased solubility in drying step. • Elastic modulus of starches was increased obviously after drying step. [ABSTRACT FROM AUTHOR]

The contribution of starch to dough behaviors has been largely overshadowed by the role of gluten, receiving much less attention in comparison. The impact of wheat starch granule size on the viscoelastic behaviors of low-moisture noodle dough and its underlying mechanism were investigated. Dough with a high ratio of B-type starch granules (BS) had higher viscoelastic moduli (G″ and G′) and percent stress relaxation (SR%), and lower creep compliance (J max), indicating higher viscoelasticity and strength. This might be related to the higher filling ability and water-binding capacity of B-type starch. Compared to large A-type starch granules (AS), small B-type granules would easily embed to form a more closely packed and uniform network structure. In addition, the differences in water distribution and hydration properties could affect the hydrophobicity of starch and the surface environments of the protein, thus influencing the polymer interactions in the doughs. The hydrogen bonds were the main con-covalent bonds in the low-moisture noodle dough. With increasing B-/A-type starch ratios, β-sheet and hydrogen bond contents significantly increased, while the SDS-extractable protein content also increased, suggesting the enhanced hydrogen bond interaction in a high ratio of B-type starch dough could cooperate with intermolecular disulfide bonds to stabilize the network structure of gluten, improving the dough strength. These results demonstrated that the viscoelastic behaviors of dough sheet were closely related to the granule size distribution of wheat starch. Finally, a schematic model describing the mechanism of the influence of starch granule size on dough behaviors was built. [Display omitted] • B-type wheat starch granules promoted uniform and compact gluten network formation. • Small B-type granules led to stronger hydrogen bond interaction in the noodle dough. • The enhanced interaction by hydrogen bonding could improve the dough strength. • Viscoelasticity of dough sheet increased with increasing B- to A-type starch ratios. [ABSTRACT FROM AUTHOR]

• Both salt and kansui could increase the rupture stress. Salt could increase while kansui decrease the rupture elongation. • The large polymeric glutenin (LPP) disaggregated from glutenin macropolymer (GMP) through physical disentanglement. • The addition of kansui especially at 1% concentration could inhibit the disaggregation of GMP through protein cross-linking. Effects of different levels of salt (1–2%, fwb) and kansui (0.5–1%) on the rheological, chemical and structural characteristics of noodle dough developed by repeated sheeting were studied. The rupture stress was increased by salt and kansui. The rupture elongation was increased by salt while reduced by kansui. The rupture stress and elongation increased to a maximum at 3 or 4 sheeting passes then decreased. The larger polymeric glutenin (LPP) increased while glutenin macropolymer (GMP) and free SH contents declined with the increased sheeting passes except for the dough contained 1% kansui at which these indicators remained constant. The β-sheet was increased while the β-turn was decreased by salt and kansui. The results showed the LPP disaggregated from GMP through physical disentanglement and experienced a reaggregation process with the SS bonds participate in, but the addition of kansui especially at 1% concentration could inhibit the disaggregation of GMP through protein cross-linking. [ABSTRACT FROM AUTHOR]