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The mechanism by which the heat-moisture induction of a gel-entrapped network affects the texture of Tartary buckwheat noodles was explored by studying starch gelatinisation, starch crystallinity and molecular weight, proton mobility, and microstructure of noodles prepared from extruded starch (ES) and Tartary buckwheat flour during cooking. Noodles with higher ES content showed higher hardness and chewiness during cooking for 4.5 min, whereas the hardness was reduced after optimal cooking.Starch-lipid complexes (SLCs) collapsed and the entrapped networks were disrupted during optimal cooking, while overcooking led to the escape of starch molecules from the noodles and reduced the textural hardness. Proton migration and microstructure evaluations confirmed that water migration was stronger and more cavities appeared in the gel-entrapped network of noodles overcooking. Therefore, the disintegration of SLCs and the appearance of cavities in the gel-entrapped network were closely associated with the deterioration of the texture of noodles. [Display omitted] • Higher levels of extruded starch (HL-ES) retarded starch gelatinisation in noodles. • HL-ES promoted the decrease of noodle hardness after optimal cooking. • HL-ES inhibited the production of new starch-lipid complexes in cooked noodles. • Disruption of starch-lipid complexes (SLCs) promoted more voids in the gel network. • Disruption of SLCs and gel network both promoted deterioration of noodle texture. [ABSTRACT FROM AUTHOR]

Abstract Products fermented by probiotics are consumed worldwide and play important roles in human nutrition and health. In this study, the effects of fermented and unfermented Agaricus bisporus polysaccharide (FABP and UABP) flours on the structural and antioxidant properties of composite gluten-free (CGF) doughs and cookies were investigated. The extracted Agaricus bisporus polysaccharide flour was subjected to fermentation by Lactobacillus plantarum at 37 °C for 72 h. Incorporation of both FABP flour and UABP flour resulted in larger interconnected structures in doughs, with smoother surfaces being observed compared to the control. Moreover, FABP flour formulations showed higher total phenolic content (20.07–28.12 mg GAE/g, dwb), ABTS radical scavenging activity (82.17–86.82%) and β-carotene bleaching (68.80–83.72%), and UABP flour formulations had greater reducing power (0.61–0.83) and DPPH radical scavenging activity (78.66–91.22%), whereas less antioxidant activity was found in the control. Aggregated spherical granules were observed in all micrographs of CGF cookie formulations, and the control showed both individual and aggregated spherical granules. Several protein bands (20.1, 21.1, 32.0 and 33.1 kDa) with higher intensities were detected in all CGF cookie formulations compared to the control. Overall, the inclusion of mushroom polysaccharide flours could enhance the antioxidant attributes and alter structural characteristics of CGF cookies. Graphical abstract Image 1 Highlights • Novel CGF cookies were prepared by added FABP flour and UABP flour. • CGF cookies after adding polysaccharide flours exhibited different micrographs. • An increase of total phenolic content and antioxidant activities was observed. • Several protein bands were found in the fortified CGF cookies. [ABSTRACT FROM AUTHOR]

We examined the physicochemical and functional properties of whole grain flour (WGF) treated with ozone gas at 5 g/h for 0, 5, 15, 35, and 45 min. The water and oil absorption, swelling power, and solubility all increased significantly with increasing ozonation time, while the pasting properties showed significant decreases in peak viscosity, trough, breakdown, final, and setback viscosity values (all p  ≤ 0.05). Structural analysis revealed changes in the intensities of the O–H, C–H, and CH 2 bending vibrations of protein side chains and lipids with increasing ozonation time. Ozone affected the mean particle size of WGF. Confocal laser scanning microscopy examination of WGF revealed remarkable differences between control and treated flours. [ABSTRACT FROM AUTHOR]

We treated whole grain flour (WGF) with ozone gas applied at 5 g/h over intervals of 0, 5, 15, 35, and 45 min. We extracted oil from whole grain flour treated and untreated with ozone gas to investigate how the ozone affected the fatty acid composition. The fatty acid value decreased in the treated flour, whereas the peroxide and p -inisidine values increased with ozone gas treatment. The lipase activity was lower in oil extracted from the flour that had been ozonated for more than 35 min compared to the control sample. We also observed levels of oxidation in the volatile compounds heptanal, hexanal, tetradecane, decanal, 1-hexanol, and nonanal after ozone treatment. The oils extracted from the ozone-treated flour showed higher phenolic content and antioxidant activity. [ABSTRACT FROM AUTHOR]

Superfine green tea powder (SGTP) was premixed with organic acids (ascorbic acid, citric acid) and hydrocolloids (sodium alginate, curdlan), and then mixed with microwave-treated wheat flour to produce green tea fresh noodles (GTFN). Darken-retardant effects of organic acids, hydrocolloids and microwave treatments on GTFN were evaluated, as well as pH, polyphenol oxidase activity, sensory and microstructure characteristics. The results revealed that organic acids exhibited a suppressive effect on discoloration, among which citric acid (CA) displayed more efficient influence with lower pH. After adding hydrocolloids and microwave treatments, retardant effects exhibited more significant (P < 0.05). Specifically, employing citric acid 0.6 g/100 g, sodium alginate 0.2 g/100 g, and 800 W microwave (MW) 50 s would contribute to lower darkening index ΔE * (24 h, 25 °C) at 3.88 ± 0.314, 4.94 ± 0.297, 2.78 ± 0.212, respectively. Furthermore, the combined effect of the above process restrained discoloring rate considerably (ΔE * = 1.92 ± 0.101), also provided pleasant sensory characteristics. The confocal scanning laser microscopy (CSLM) images demonstrated the microstructure of the noodle was strengthened compared with blank GTFN, and sodium alginate could serve as a binding agent to parcel SGTP and starch granules. [ABSTRACT FROM AUTHOR]

Abstract: In this work, an ultrasound-assisted procedure for the extraction of defatted wheat germ proteins by reverse micelles was established. Response surface methodology (RSM) was used to optimize the ultrasound-assisted extraction (UAE) parameters (ultrasonic output power, ultrasonic time and pulse mode) for enhancing the forward extraction efficiency of defatted wheat germ proteins by implementing a three-level, three-variable Box–Behnken experimental design. The independent variable with the largest effect on response was X 2 (ultrasonic time), followed by X 1 (ultrasonic output power) and X 3 (pulse mode). The optimum extraction conditions were found to be ultrasonic output power 363W, ultrasonic time 24min and pulse mode 2.4s on and 2s off (2.4s:2s). Under these conditions, the forward extraction efficiency of defatted wheat germ proteins can increase from 37% to 57%, and the final protein extraction efficiency by reverse micelles can reach 45.6%, making the advantage of reverse micelles much more obvious than alkaline extraction and isoelectric precipitation on the separation of protein. [Copyright &y& Elsevier]

Abstract: In this work, the forward extraction of defatted wheat germ protein (DWGP) by reverse micelles was studied. The reverse micellar systems were formed by sulphosuccinic acid bis (2-ethylhexyl) ester sodium salt (AOT), isooctane and KCl solution. The effects of AOT concentration, pH, KCl concentration, extraction time, the amounts of defatted wheat germ flour (DWGF), W 0 (the molar ratio of water to surfactant, i.e. W 0 =[H2O]/[AOT]) and temperature on the forward extraction efficiency of DWGP were tested. On the basis of single-factor experiments, the optimum extraction was achieved by response surface methodology (RSM). The experimental results lead to the conclusion that the highest forward extraction efficiency of DWGP was reached at the AOT concentration 0.06g/mL, pH 8, KCl concentration 0.1mol/L, time 30min, the amounts of DWGF 0.500g, W 0 25 and temperature 36°C. Under these conditions, the forward extraction efficiency of DWGP achieved 37%. [Copyright &y& Elsevier]

In this research, changes in microbial shelf-life and quality characteristics of fresh wet noodles (FWNs) were analyzed under acid and different mild heat treatment conditions. Acid combined with heat treatment at 50 °C for 30 min extended the shelf-life of FWNs by 30–40 d and effectively delayed the color deterioration of FWNs. The water absorption of FWNs was reduced by the mild heat treatment. Meanwhile, the cooking loss of the noodles and hardness significantly (p < 0.05) increased. Differential scanning calorimetry (DSC) analysis showed that the gelatinization enthalpy of the starch in FWNs decreased and the gelatinization temperature increased. The X-ray diffraction (XRD) results showed that the crystallinity of the starch decreased from 27.51% to 24.2% after mild heat treatment. In addition, it was observed by confocal laser scanning microscope that the mild heat treatment made the gluten networks more continuous. The free sulfhydryl content of noodles showed a decreasing trend, while the sodium dodecyl sulfate-extractable protein (SDS-EP) value was also significantly (p < 0.05) reduced. Overall, the combination of mild heat treatment with acid extended the shelf-life of FWNs and had less impact on their quality. [Display omitted] • Acid and mild heat treatment (AMHT) prolonged the shelf-life of fresh wet noodles. • AMHT increased the hardness of noodles and reduced elasticity and water absorption. • AMHT increased the formation of protein network in noodles. • AMHT altered the pasting properties and relative crystallinity of starch in noodles. [ABSTRACT FROM AUTHOR]

Temperature fluctuations during transportation all the way to consumption can negatively affect the quality of frozen cooked noodles (FCNs). In response, this work investigated whether gellan enhanced the appearance and texture property of FCNs during freeze-thaw cycles. Compared with the control, adding gellan increased the hardness of FCNs and reduced structural damage during freeze-thaw cycles. In addition, changes in FCNs were explained from the perspectives of freeze-thaw stability and rheology, the former of which was determined according to T 2 relaxation time, magnetic resonance imaging (MRI), and differential scanning calorimetry (DSC). The results showed that adding gellan reduced the percentage of weakly bound water and the relaxation time of FCNs, as well as increased the water-holding capacity of the noodles. MRI pseudo-color maps illustrated that adding gellan stabilized the water gradient in the noodles, and a thermal analysis of FCNs via DSC demonstrated that adding gellan at 0.3% maximized the melting termination temperature. In addition, creep-recovery test results indicated that FCNs compliance increased during freeze-thaw cycles, and the addition of gellan enhanced the zero-shear viscosity and deformation resistance, which explained the texture property change of FCNs. [Display omitted] • The hardness of frozen cooked noodles (FCN) decreased during freeze-thaw cycles. • Gellan was beneficial to the quality of FCN. • The addition of gellan increased the water-binding capacity of FCN. • Added gellan enhances the freeze-thaw stability of FCN. • Adding gellan increased the zero shear viscosity and deformation resistance of FCN. [ABSTRACT FROM AUTHOR]

Phytic acid (PA) could increase the yellowness value of yellow alkaline noodles (YAN), as well as significantly reduce the generation of dark spots on the surface of YAN by suppressing polyphenol oxidase (PPO) browning. In this paper, the inhibition mechanism of PA on PPO browning was mainly studied. In the produced YAN sheets, the PPO activity and free quinone content showed a gradual decrease with increasing PA addition, while the free phenol content gradually increased. This indicated that PA could inhibit PPO browning and was an effective browning inhibitor. In the constructed in vitro PPO solution, the anti-PPO browning mechanism of PA was mainly through chelating Cu2+ in the active center. The DPPH radical scavenging rate of PA was measured, and it was found that PA could inhibit PPO browning, which was related to the antioxidant capacity. The effect of PA on browning products was analyzed using HPLC, and the results of the study showed that PA could reduce the peak area of the browning products, thus reducing the generation of dark spots. [Display omitted] • PA (phytic acid) can effectively improve the appearance of yellow alkaline noodles. • PA significantly reduces the generation of dark spots by inhibiting PPO browning. • PA inhibits PPO activity mainly by binding to active center Cu2+. • PA can enhance the scavenging rate of DPPH free radicals. • PA can reduce the formation of browning products by HPLC analysis. [ABSTRACT FROM AUTHOR]

Chinese traditional handmade hollow dried noodle (HHDN) is a popular wheat-based food among the Chinese people due to its easy cooking qualities and smooth texture, which are significantly correlated with the rheological characteristics of HHDN dough. The effects of water content (55, 60, and 65%) and resting time (0, 30, 60, 90, and 120 min) on the rheology and gluten network formation of the HHDN dough were investigated. The modulus during stress relaxation reduced from 8.62 Pa to 2.30 Pa as the water content increased from 55% to 65%. With resting time increased from 0 min to 120 min, the extensibility of the 60% water content dough increased from 64.33 mm to 152.67 mm. With the water content decreased and resting time increased, the glutenin macropolymer (GMP) content increased and the free sulfhydryl content decreased. The microstructure study of the dough showed that extending the resting time was beneficial to the formation of the gluten network. The covalent interactions promote the formation of the gluten network and change the rheological properties of the dough. The dough with 60% water content and 60 min resting would result in the desired quality of the dough, ultimately improving the quality of the noodles. [Display omitted] • Researched the linear and nonlinear viscoelastic properties of the dough. • The formation of gluten network improves the rheological properties of dough. • Covalent interaction affects the formation of gluten network. • The GMP content increases as the resting time increases. [ABSTRACT FROM AUTHOR]

Changes in the properties of major components (gluten protein and starch) of frozen raw noodles (FRN) during twelve-week frozen storage were investigated. Frozen storage induced quality deterioration to FRN. Increases in optimal cooking time and cooking loss of FRN were determined. The hardness of noodle texture increased in the first six weeks and then decreased. The gluten from FRN showed decreases in the glutenin fractions with prolonging frozen storage. The compliance (J) of the gluten tended to decrease after the third week, accompanied with increasing zero-shear viscosity (η). The rheological parameters indicate the gluten of FRN became stiffer and less flexible in the latter frozen storage. With prolonging frozen storage, the starch of FRN exhibited higher short-range ordered degrees, revealing the increasing compactness of starch structure which contributed to the longer optimal cooking time required for FRN. Increasing yield stress (σ 0) values derived from steady rheological tests indicate the greater force required for the starch gel to initiate flow, which was corresponding to the higher noodle hardness after six weeks. It was concluded that frozen storage induced changes in quality properties of FRN by altering the gluten and starch components. [Display omitted] • Frozen storage caused worse cooking and texture properties of frozen raw noodles(FRN). • Rheological tests showed the gluten became stiffer and less flexible in latter period. • Higher starch short-range orders were related to longer optimal cooking times of FRN. • Greater yield stress (σ 0) of starch gel was related to the greater noodle hardness. • Frozen storage induced quality loss to FRN by altering gluten and starch components. [ABSTRACT FROM AUTHOR]

The impacts and mechanisms of ascorbic acid (Vc) and sodium dihydrogen phosphate on the browning of yellow alkaline noodles were investigated. The combination of sodium dihydrogen phosphate and Vc was found to increase the L* value and decreased the number of dark spots, indicating a synergistic anti-browning effect. This combination reduced the activity of polyphenol oxidase (PPO) slightly but deceased the free quinone content significantly (P < 0.05) in noodles. The addition of sodium dihydrogen phosphate also maintained the anti-oxidation stability of Vc, as evidenced by the increased DPPH radical clearance rate in PPO-catechol systems after 24 h of storage. Quantum chemical calculations revealed that sodium dihydrogen phosphate formed hydrogen bonds with ascorbic acid at hydroxyls of carbon-carbon double bond, which protected the ascorbic acid to some degree. This finding suggested that the synergistic anti-browning capacity of sodium dihydrogen phosphate and Vc could be applied to the noodle processing industry. [Display omitted] • The combination of Vc (ascorbic acid) and sodium dihydrogen phosphate (SDP) inhibited the browning of noodles. • The combination of Vc and SDP showed the synergistic anti-browning capacity. • The addition of Vc and SDP decreased the PPO activity and quinone content. • The addition of Vc and SDP increased in DPPH radical clearance. • The interaction between Vc and SDP was explored using quantum chemical calculations. [ABSTRACT FROM AUTHOR]

The effects of tempering with phosphoric acid (PA) and potassium carbonate (PC) solutions on the microbial load and the quality of wheat flour and fresh noodles (FNs) were studied. With the increase of PA/PC concentration, total plate count (TPC) and mold and yeast count (MYC) of tempered wheat kernels and flour streams decreased significantly (p < 0.05), and 3B and 3M flour streams had the greatest microbial reduction. PA/PC tempering had little effect on grinding characteristics of wheat kernels. Specifically, the whiteness of the obtained straight-grade flour increased and polyphenol oxidase (PPO) activity decreased significantly (p < 0.05) and the pH and acidity changed slightly. RVA and Mixolab showed that the pasting viscosity decreased slightly after PA tempering, and the protein strength increased slightly after PC tempering. The initial microbial quantity and browning rate of FNs made from flour obtained from wheat tempered with PA/PC solutions decreased significantly (p < 0.05) and the texture characteristics of FNs were significantly enhanced (p < 0.05). The results showed that tempering with PA/PC solutions could effectively reduce the microbial content of flour streams without detrimental effects on the quality of flour and FNs. [Display omitted] • PA/PC tempering reduced the microbial load of tempered wheat kernels and six flour streams. • PA/PC tempering was more effective for microbial reduction of 3B and 3M flour streams. • PA/PC tempering reduced PPO activity of bran and flour and increased the whiteness of flour. • PA/PC tempering reduced the initial microbial load and browning rate of fresh noodles. • PC tempering improved the dough structure of flour and texture properties of fresh noodles. [ABSTRACT FROM AUTHOR]

In this study, the effects of microwave treatment on the microorganism mortality and PPO activity in whole-wheat flour (WWF) and storage stability of WWF fresh noodles were investigated, as well as the rheological properties of WWF, viscosity and gelatinization properties of starch component, and polymerization and conformational changes of protein. TPC and PPO activity were largely reduced in WWF treated for over 60s. Moreover, it was amazing that microwave treatment significantly increased ( P < 0.05) dough stability and the resistance to extension. Peak and final viscosity of starch were increased after microwave treatment, with no observable loss of birefringence; SDS-extractable proteins were limitedly decreased and protein aggregating occurred mainly on the large and medium glutenin polymers as shown by the SE–HPLC profiles. In addition, microbial growth and darkening rate of WWF fresh noodles were significantly inhibited, shelf-life of the samples was extended for 3 times after treating for 90 s. [ABSTRACT FROM AUTHOR]

Pasteurization, acidification followed by pasteurization, and autoclave extended the shelf-life of cooked noodles (groups S1, S2 and S3) to 3, 180 and 180 days, respectively. Pasteurization increased the hardness of cooked noodles from 53.60 to 58.01 N. However, the growth of thermoduric bacteria caused a decrease in pH, coloration, and hardness of group S1 during storage. Meanwhile, the pH and hardness of group S2 decreased to 4.42 and 39.22 N respectively, while hardness and chewiness increased during storage. In addition, physicochemical-textural characteristics of group S3 are maintained throughout storage. The hardness of groups S1 and S2 is related to the gluten structure. The compact gluten network formed after pasteurization. Meanwhile, acidification inhibited the polymerization of glutenin and gliadin. The starch melted after autoclave, masking the impact of the gluten network and decreasing hardness. During storage, hydrolysis of protein and starch by bacteria resulted in the deterioration of group S1. Recrystallization of starch resulted in the stiffening of group S2. The absence of metabolism of bacteria and presence of stable gluten in group S3 contributed to the stable starch structures, inducing its stable quality. Thermal treatment can be recommended as an effective additional treatment for producing shelf-stable wet instant cooked noodles. • Autoclave maintained the quality of wet instant cooked noodles during storage. • Non-disulfide covalent bonds between glutenin and gliadin were formed during autoclave. • Acidification hindered crosslinks between glutenin and gliadin. • Complete melting of starch crystalline decreased the hardness of noodles. [ABSTRACT FROM AUTHOR]

Wheat bran is good for human health due to the abundance of dietary fiber. However, it also contains much phytate which has been well documented as an anti-nutritional factor. This study is the first to explore the effectiveness of reducing phytate content in wheat bran by directly removing the aleurone cell content utilizing different roller mills (smooth roller, coarse smooth roller and teeth roller) and different clean-up methods (brushing and ultrasonic washing). Through analysis of phytate content in wheat bran obtained from different mill systems, the best raw material was found to be obtained from the 5B system. By investigating various roller types and clean-up methods, the optimal technique was found to use a teeth roller mill combined with ultrasonic washing, which could reduce the phytate content by the greatest amount: the reduction of phytate content achieved 62.98% (from 26.80 mg/g to 9.92 mg/g) in wheat bran. The optical microscope observation indicated that ultrasonic washing could wash the aleurone cell content out from broken aleurone cells which were destroyed by the teeth roller mill. [ABSTRACT FROM AUTHOR]

In this study, the effect of steaming on the quality of frozen cooked noodles was investigated, as well as the microstructure, protein extractability and starch properties of steamed noodles. Furthermore, white salted, yellow alkaline and control noodles (without salt or alkaline) were measured as affected by different steaming times. The results indicated that the cooking and texture properties of frozen cooked noodles were significantly ( P < 0.05) improved by steaming pretreatment, except that yellow alkaline noodles showed larger cooking loss. In addition, steamed noodles except yellow alkaline noodles had compact and smooth surfaces compared with fresh noodles. With the increase of steaming time, the SDS extractable protein and RVA viscosity properties of starch decreased. Gelatinization enthalpy of starch in steamed noodles decreased dramatically upon steaming. The present study indicated that protein polymerization and starch gelatinization when subject to limiting water conditions during steaming accounted for improved noodle quality. [ABSTRACT FROM AUTHOR]

Nonthermal plasma-activated water (PAW) was prepared and used as wheat tempering water. The effects of tempering with PAW on total plate count and quality properties of wheat flour streams were studied. With the extension of plasma activation time, the content of NO 3 −, NO 2 − and H 2 O 2 in PAW significantly increased, and pH decreased dramatically (p < 0.05). After tempering with PAW activated for 40 min, total plate counts in bran, low-grade and patent flour were significantly decreased by 68.85%, 60.91% and 27.27%, respectively (p < 0.05). The polyphenol oxidase, lipase and lipoxygenase activities in low-grade flour markedly decreased by 41.27%, 18.07% and 31.42%, respectively, with the treatment of PAW (p < 0.05). Rapid Visco Analyzer results showed a decrease in peak, trough and final viscosity of straight-grade flour. The free sulfhydryl content in straight- and low-grade flour also decreased. Mixolab test showed there was no significant change in dough rheological characteristics of straight-grade flour. Overall, tempering with PAW could be a promising nonthermal technique to decrease the microbial loads of flour without obvious detrimental effects on its processing quality. [Display omitted] • PAW was used as tempering water to reduce microbial loads of flour streams. • Tempering with PAW inhibited the enzymes activity in bran and low-grade flour. • Tempering with PAW reduced the paste viscosity and free sulfhydryl content of flour. • Tempering with PAW could maintain the processing properties of flour. [ABSTRACT FROM AUTHOR]

To improve highland barley noodles (HBNs) quality, the highland barley flour (HBF) was pre-fermented by Lactobacillus plantarum in this study. The changes in the quality of HBNs, the hydration properties and microstructure of the dietary fiber (DF), and the conformation and cross-linking of the protein in HBNs were measured. With the extension of pre-fermentation time (0–4 h), the overall acceptance of HBNs increased from 7.83 to 8.27, along with a 5.9% reduction in hardness and a 4.5% increase in springiness of HBNs. Meanwhile, confocal laser scanning microscopy (CLSM) revealed that the physical structure of the DF gradually disintegrated, which caused a significant (p < 0.05) decrease in its water retention capacity. In addition, spectral analysis showed a continual increase (from 19.62% to 30.15%) in β-turn content of the protein. The content of the free sulfhydryl group and sodium dodecyl sulfate extractable protein (SDSEP) decreased by 18.1% and 4.12%, respectively. However, with the further extension of pre-fermentation time (6–8 h), the degradation in HBNs sensory quality occurred, accompanied by a significant (p < 0.05) decrease in pH (5.95–5.01). These findings suggested that a moderate duration (4 h) of HBF pre-fermentation could effectively improve the quality of HBNs. [Display omitted] • HBF pre-fermentation by Lactobacillus plantarum degraded the dietary fiber. • HBF pre-fermentation by Lactobacillus plantarum weakened the water-binding capacity of dietary fiber. • Highest sensory quality of HBNs was obtained by 4 h of HBF pre-fermentation. • Optimal network structure in HBNs was formed through 4 h of HBF pre-fermentation. [ABSTRACT FROM AUTHOR]

Abstract: Superfine green tea powder (SGTP) was used to substitute 0g, 1g, 2g, and 3g of 100g wheat flour (defined as 0SGTP, 1SGTP, 2SGTP and 3SGTP respectively) to make fresh noodles. The effects of SGTP on the viscosity, thermodynamic and rheological properties of wheat flour were evaluated, as well as the sheet colour, cooking quality, texture properties and sensory characteristics of green tea noodles. The results revealed that the stability, elastic modulus (G′) and viscous modulus (G″) of wheat dough all increased with the increase of green tea powder proportion. No significant differences were found in gelatinisation properties of the green tea-flour systems. Furthermore, adding SGTP could significantly (P <0.05) retard the retrogradation of the gelatinised wheat flour gel. L ∗ value of fresh noodles decreased as SGTP content increased while |a ∗| value firstly increased and then decreased at 3g/100g. The 2SGTP noodle samples showed the least cooking loss. Sensory evaluation indicated that the control and the 2SGTP fresh noodles scored significantly (P <0.05) higher in terms of colour. No significant difference was detected for the mouthfeel and overall acceptability among all samples. [Copyright &y& Elsevier]

Effects of different wheat bran pre-treatments on storage stability and physico-chemical properties of semi-dried whole wheat noodles (SWWN) were investigated. After bran pre-treatment with liquor koji and yeast, the total plate count of SWWN showed a slower rate of growth and the shelf-life was prolonged, which could be related to the lower pH and higher content of ethanol in noodles. Furthermore, liquor koji and yeast fermentation (LKYF) treatment reduced the optimal cooking time and cooking loss and increased the hardness of SWWN (P < 0.05). The appearance and cross-sectional microstructure of noodles in LKYF changed obviously. Irregular pores in noodles were observed by SEM, which were caused by the gas production during noodle processing. This change had positive effects on the cooking quality and texture property of noodles. The present study showed that bran treatment with LKYF could improve the storage stability and quality characteristics of SWWN. • Liquor koji and yeast pre-fermented bran extended the shelf life of noodles. • Bran pre-fermentation reduced cooking time and cooking loss of noodles. • Bran pre-fermentation decreased pH and increased ethanol content of noodles. • Liquor koji and yeast pre-fermented bran changed appearance of noodles. • Irregular pores in noodles were observed by SEM owing to bran pre-fermentation. [ABSTRACT FROM AUTHOR]

The color of dried green tea noodles (DGTN) is a crucial determinant of consumer acceptance. Although polyphenol oxidase (PPO) is a key factor inducing the darkening of noodles, its contributions on the discoloration mechanism of DGTN requires clarification. Results revealed that PPO induced the decreased of lightness L value and greenness |a| value via its effects on polyphenol compounds and chlorophyll during the processing of DGTN. The increase of PPO activity significantly accelerated the discoloration rate and the degradation of chlorophyll during storage of the DGTN. Correlation analysis found that the changes of chlorophyll among DGTN made from different PPO activities of wheat flour played a major role in the discoloration. These findings indicated that the control of the negative effects of PPO on polyphenol compounds and chlorophyll could be an effective method to retard discoloration in DGTN. • Polyphenol oxidase is crucial to the discoloration of dried green tea noodles. • Polyphenol oxidase significantly accelerates the lightness and greenness variations. • As polyphenol oxidase increases, the content of phenolic compounds and chlorophyll decreases. • The degradation of chlorophyll is a key factor in the discoloration of dried green tea noodles. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the impact of different mixing and kneading processes on the qualities of frozen cooked noodle were evaluated, including freezable water content and microstructure of the noodle, as well as rheological properties of dough. The results showed that the frozen cooked noodle of manual dough mixing (MM) scored the highest in sensory evaluation, while the one via vacuum dough mixing (VM) way had the best texture and cooking properties with lower water absorption and cooking loss under the same kneading process. The vacuum condition could contribute to a more uniform and continuous matrix of protein during the mixing process. Besides, both machine kneading (MK) and hand kneading (HK) process displayed a significant (p < 0.05) positive effect on the qualities of frozen cooked noodle, such as texture properties, cooking properties, and sensory score. Furthermore, the role of hand kneading process was more evident than machine kneading. Highlights • Systematic study of mixing and kneading process on the effects of noodle's quality. • Frozen cooked noodle's qualities were significantly improved by vacuum mixing. • Kneading process was benefit for the high qualities of frozen cooked noodle. • Hand kneading process has the most significant effect on the noodle's qualities. [ABSTRACT FROM AUTHOR]

We investigated the impact of table (NaCl) and alkaline (kansui) salts on changes to the gluten network during fresh wheat noodle production and cooking. Noodle production did not markedly change the gluten structure. In contrast, cooking increased gluten's average molecular weight by disulfide bond formation or reshuffling as evidenced by the decrease of protein extractability. Addition of NaCl (0.5 up to 3.0 weight % on flour basis) to the recipe reduced the extent of gluten polymerization during cooking. Kansui (0.2 up to 1.5 weight %) increased intermolecular disulfide bond formation. Furthermore, amino acid analysis revealed that kansui induced the formation of dehydroalanine-derived cross-links lanthionine and lysinoalanine. Optimal firmness was observed for noodles containing either 0.2–1.5% kansui or 2.0% NaCl. However, the addition of kansui reduced noodle nutritional quality, and high levels of table (2.0–3.0%) or alkaline (1.0–1.5%) salt increased cooking losses. [ABSTRACT FROM AUTHOR]

Effects of extruded endogenous starch (EES) on the gel-entrapped network formation in Tartary buckwheat noodles (GF-TBNs) during sheeting were studied. EES was obtained at different extrusion temperatures and mixed with buckwheat flour to prepare GF-TBNs. Higher temperatures (>110 °C) no longer promoted the decrease in the molecular weight of starches. The gel strength of EES could be related to molecular distribution internal EES. Furthermore, the n ′ of GF-TBN dough sheets decreased and G 0 ' increased as the sheeting roller gap reduced, which suggested that the gel network in sheets was extended. The sheeted noodles had higher tensile strength, elasticity and fracture work, which was benefited from the extended gel network. Microstructure images and vascular fitting analysis confirmed the formation of a denser network in the noodles after sheeting. These results indicated that EES gel provided viscosity to the dough and sheeting promoted the formation and extension of gel networks in GF-TBNs. • Higher temperatures no longer promote a decrease in the molecular weight of starch. • Extruded starch gel gave the viscosity of gluten-free noodle (GFN) dough. • The reduction of the roller gaps contributed to increasing the G′ of GFN dough. • Sheeting promoted the formation and extension of gel networks in GFNs. • The extended gel network tended to improve the tensile strength of GFNs. [ABSTRACT FROM AUTHOR]

In this study, the effects of acidity regulators (ARs) on the shelf life, quality, and physicochemical characteristics of fresh wet noodles (FWNs) were investigated. The addition of ARs markedly reduced the pH value of FWNs with a prolonged microbial shelf life of 5–10 days. Moreover, the presence of ARs significantly (p < 0.05) decreased the hardness and tensile distance of cooked FWNs, while increasing the cooking loss of noodles significantly (p < 0.05). The results of confocal laser scanning microscope analysis showed that ARs inhibited the formation of gluten networks in cooked noodles. Sodium dodecyl sulfate-extractable protein (SDS-EP) and free –SH content increased significantly (p < 0.05) when ARs were added. ARs affected the polymerization of proteins by inhibiting the formation of interchain disulfide bonds during cooking. Moreover, X-ray diffraction results showed that the addition of ARs resulted in acid hydrolysis of the amorphous area of the starch in FWNs, decreasing the pasting temperature, peak and trough viscosities of the starch. The reduction in pH value was the main factor that affected the shelf life and quality of FWNs, but different types of ARs had no significant impact. [Display omitted] • Adding acidity regulators (ARs) markedly prolonged shelf life of fresh wet noodles. • ARs reduced the hardness and elasticity of noodles and increased cooking loss. • ARs inhibited the formation of protein networks during cooking. • A decrease in pH value inhibited the formation of interchain disulfide bonds. • ARs changed the pasting properties and relative crystallinity of starch in noodles. [ABSTRACT FROM AUTHOR]

The aim was to investigate whether extrusion could improve the storage stability of dried oat noodles by inhibit lipid-degrading enzyme activity and the degradation of lipids. Thus, noodles were made from extrusion-treated oat under two treatment conditions and subjected to 12-week storage. Extrusion completely inactivated lipase and peroxidase in oat flour, while lipoxygenase activity persisted at a low level. Processing of dried oat noodles also influenced enzyme activity dramatically. For instance, the most significant impact was observed for lipase activity, which dropped to ca. 11 U∙min−1∙g−1 in the freshly prepared noodles made from non-heat-treated oat flour. Lipid hydrolysis was greatly controlled in extrusion-treated noodles as fatty acid values did not increase during storage. The total lipids decreased more in the extrusion-treated groups than in the control sample, which may indicate the promotion of extrusion in non-enzymatic reactions, as the initial values of volatile compounds were much higher. Interestingly, the occurrence of non-enzymatic lipid oxidation should not be severe during storage, as the reduction of tocols and the accumulation of volatile compounds were only moderate in extrusion-treated oat noodles. In conclusion, extrusion could be an effective method for enhancing the storage stability of dried oat noodles. [Display omitted] • Lipase and peroxidase were completely inhibited by extrusion in dried oat noodles. • Lipoxygenase persisted activity at low level after extrusion. • Enzymatic reaction was the main factor to cause lipid-degradation during storage. • Formation of volatile lipid oxidation products was greatly controlled by extrusion. • Extrusion may confer some advantages in the production of stable oat food products. [ABSTRACT FROM AUTHOR]

Kongxin (hollow) noodle is a traditional staple food in China and is well-known for its high eating quality. To meet the growing need of market, modern machine and fermentation technique have been applied to produce Kongxin noodles. In order to achieve high quality of food product, the effect of sodium bicarbonate (NaHCO 3) ranging from 0 to 4 g/kg flour on quality of machine-made Kongxin noodles was investigated. The addition of NaHCO 3 decreased the optimal cooking time of Kongxin noodles significantly (p < 0.05). Additionally, elasticity, firmness, chewiness of Kongxin noodles showed significant (p < 0.05) increasing trends. The improvement of NaHCO 3 to quality of noodles may be because it promoted starch gelatinization and level of gluten cross-linking. However, the addition of NaHCO 3 at 4 g/kg flour increased the cooking loss of Kongxin noodles significantly (p < 0.05), which might be because the gluten network formed by excessive crossing-linking limited the swelling of starch. Finally, the optimal cooking and textural qualities were observed at the level of 3 g/kg of NaHCO 3. In conclusion, addition of NaHCO 3 improved the quality of Kongxin noodles by promoting starch gelatinization and gluten cross-linking. [ABSTRACT FROM AUTHOR]

Wheat tempering was conducted with slightly acidic electrolyzed water (SAEW) at different active chlorine contents. Microbial, biological, and chemical properties of different flour streams milled from SAEW-tempered wheat grains were investigated. Results showed that the total plate count (TPC) and yeast/mould count (YMC) in flour products were significantly (p < 0.05) reduced as SAEW concentration increased. The total polyphenols, lipase (LA) activity, polyphenol oxidase (PPO) activity of clear flour and bran, along with starch viscosity and protein extractability under reduced conditions of clear flour were all decreased significantly (p < 0.05) when SAEW concentration raised. Meanwhile, farinograph properties of clear flour were slightly improved. However, there was no significant (p > 0.05) difference in biological and chemical characteristics of straight flour. Based on our findings, SAEW has potential to function as a novel tempering solution for producing clean flour. • Wheat grains were tempered by SAEW to reduce microbes in flour streams. • SAEW treatment showed few negative impact on the properties of straight flour. • Tempering with SAEW inhibited the enzyme activity in bran and clear flour. • Tempering with SAEW reduced the starch viscosity of clear flour. • Tempering with SAEW improved the dough structure of clear flour. [ABSTRACT FROM AUTHOR]