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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]

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]

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]

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]

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]

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]

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]