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The water mobility, state and textural properties of Chinese fresh noodles (CFNs) and Chinese dried noodles (CDNs) made from same wheat cultivar were measured during boiling using low‐field nuclear magnetic resonance (LF‐NMR), low‐field nuclear magnetic Imaging (LF‐NMI) and a textural analyser. ‘The oil immersion method’ was applied to gain the clear images from LF‐NMI measurement. The distributions of the three water states (T₂₁, T₂₂ and T₂₃) in the noodles were distinguished. The results indicated that water mobility in noodles was closely related to the gelatinisation of noodle starch. Compared with CFNs, CDNs need a longer cooking time for water mobility and starch gelatinisation. The results of the cooked noodle profiles showed that the cooked CDNs (8 min) had an undesirable textural properties compared with the cooked CFNs (2 min). The longer cooking time of CDNs is responsible for its undesirable texture since the textural properties change during the longer cooking time.

Whole wheat has often been associated with health benefits conveyed by the phenolic acids made accessible in the colon which enable the modulation of the gut microbiota. In the present study, the bioaccessibility of nine individual phenolic acids present in different wheat varieties was evaluated by in vitro gastrointestinal digestion and colonic fermentation. Most of the individual phenolic acids in the complex wheat matrix had a higher bioaccessibility after the in vitro digestion step (average 57.7%–82.1%), than after in vitro colonic fermentation (21.9%–47.5%). However, the contents of cinnamic, caffeic, and protocatechuic acids in several wheat varieties were higher in the intestinal digesta than in the undigested samples, and the content of erucic acid was higher in fermented slurry than in the intestinal digesta. The bioaccessibility of certain phenolic compounds also varied significantly between different wheat varieties. Other compounds in wheat interfered with the release of phenolic acids during digestion and fermentation. The contents of phenolic acids remaining in the digesta were significantly correlated with the abundance of at least one bacterial genus during colonic fermentation. This suggests that both concentrations and food composition should be considered when selecting whole wheat with associated phenolic acids for use as potential prebiotics.

The influence of the drying conditions on protein structural properties and its impact on Chinese dried noodles (CDN) quality properties is addressed in this study. The CDN were produced under nine different drying conditions utilizing combination of three temperatures (40°C, 60°C, and 80°C) and three relative humidities (65%, 75%, and 85%). The color, texture profile analysis of uncooked and cooked noodles, shrinkage ratio, and cooking quality of CDN were assessed. SEM and FTIR microimaging were investigated to determine the changes in the gluten structural properties. Drying temperature and relative humidity have significant effects on quality characteristics of CDN. However, the influences on different indicators were different. Drying temperature was the main influencing factor of the quality of CDN and protein microstructure. After the drying temperature exceeded 60°C, proteins began to aggregate, and the surface protein distribution became uneven. Compared with cross section, the uniformity of protein distribution on the surface of noodles showed a significant decrease. A high temperature (60°C) could improve the quality of CDN products. The quality of CDN products could be adjusted by the combination of drying temperature and relative humidity.

To investigate the water mobility during a drying process, noodles were prepared with different gluten contents (10.0%, 12.5%, 15.0%, 17.5%, 20.0%, 22.5%, or 25.0%) and moisture contents (30%, 32%,...

In this study, the water state and distribution of Chinese dried noodles during drying process was investigated by low-field nuclear magnetic resonance (LF-NMR). Transverse relaxation times (T2) were achieved by LF-NMR coupled with a 0.5 T permanent magnet equivalent to a proton resonance frequency of 21 MHz at 32 °C. Three populations of water state can be distinguished: strongly bound water (T21, 0.04–0.40 ms; A21, 0.25–19.08%), weakly bound water (T22, 0.96–5.34 ms; A22, 80.81–98.44%), and free water (T23, 74.50–266.47 ms; A23, 0.11–1.61%). During the drying process, the transverse relaxation time of all water states followed decreasing trend. Initially, the moisture content decreased faster from the edges; however, moisture migrated rapidly from the central part during 90–180min. The moisture gradient disappeared after drying for 240min. Besides, a special method as "Oil immersion method" was introduced to address poor signal to noise ratio in samples when moisture content was low during the drying process. High signal to noise ratio was successfully achieved by this method.

The study aims to investigate the characterization of stable isotopic ratios in wheat milling fractions (bran, wheat shorts, and flour) and extracts (defatted flour, gluten, lipid, starch, and crude fiber) and correlations among different matrices for each isotope, which could provide some references for the development and application of stable isotopes for geographical traceability of wheat and its milling products. Wheat samples with three genotypes were collected from three regions in China. δ13C and δ15N values in wholemeal, milling fractions and extracts were determined. Results showed that δ13C varied significantly among milling fractions and extracts, while no significant difference was found among δ15N values of different milling fractions or extracts. Each isotope shows significantly positive correlations among wheat fractions (p

The impact of vacuum mixing on protein chemical structure in noodle dough was studied using three wheat cultivars. Optimum vacuum level induced a higher protein polymerization degree, compared to non-vacuum mixed dough, as evidence by results of HPSEC and glutenin macropolymer (GMP). The larger protein aggregates were observed at 0.06 MPa in dough of cultivar Jimai 22, while 0.08 MPa for Zhengmai 366 and Ningchun 4. In noodle dough, β-turn was the predominant secondary structural feature. Vacuum mixing at 0.06 MPa imparted an increase in β-turn content of Jimai 22 dough at the cost of a reduction in β-sheets, but it induced an increase in α-helix content at the cost of a decrease in β-turn for Ningchun 4 and Zhengmai 366. β-Turn content was significantly negatively associated with smaller monomeric protein percentage and positively associated with smaller polymeric protein. Better dough texture and enhanced gluten hydration might correspond to increased polymerization degree and molecular weight of protein, and more β-turn or α-helix structures.

Drying is an important operation during the production of dried Chinese noodles, and the energy consumption from drying accounts for approximately 60% of the total energy consumption during the manufacturing process. To investigate the energy consumption and throughput of dryers for dried Chinese noodles, experiments were conducted using a new 130-m long tunnel dryer with two lines of noodles (ND) and an old 60-m long tunnel dryer with five lines of noodles (OD). The energy saving effects of a modified new 130-m long tunnel dryer (MND), which was only modified through the inclusion of automatic control for temperature and humidity without any modifications to the oil heater or ND dryer structure, were also compared. The energy saving effect was determined from the enthalpy difference between the inlet and outlet humid air of the ND and MND. Finally, the MND was found to be better than ND in terms of energy efficiency and throughput, and trends for the future of noodle drying were discussed.

This study aims to investigate whether isotopic signatures can be used to develop reliable fingerprints for discriminating the geographical origin of Chinese winter wheat, and to evaluate the discrimination effects of δ(13)C, δ(15)N and δD, alone or with (87)Sr/(86)Sr. In this study, the values of δ(13)C, δ(15)N and δD, and the (87)Sr/(86)Sr ratios of wheat and provenance soils from three regions were determined. Significant differences were found in all parameters of wheat and (87)Sr/(86)Sr in soil extract (reflecting the bioavailable fraction of soil) among different regions. A significantly positive correlation was observed between the (87)Sr/(86)Sr ratios of wheat and soil extracts. An overall correct classification rate of 77.8% was obtained for discriminating wheat from three regions based on light stable isotopes (δ(13)C, δ(15)N, and δD). The correct classification rate of 98.1% could be obtained with the combination of the (87)Sr/(86)Sr ratio and the light stable isotopic values.

The objective of this study was to investigate the effects of the freezing rate and frozen storage duration on the rheological properties and protein structure of the non-fermented dough. The samples were frozen at −40 (0.149 °C/min), −30 (0.086 °C/min) and −20 °C (0.039 °C/min), and stored at −18 °C for 30 days. Freezing at −40 and −30 °C led to minimal changes in the rheological properties of the non-fermented dough. Additionally, −40 °C freezing resulted in higher maximum creep compliance (Jmax) and lower zero shear viscosity (η0). The content of glutenin macro-polymers (GMP) decreased gradually throughout the storage period, while that of free thiol groups (-SH) increased significantly, especially for samples frozen at −20 °C. Fourier transform infrared (FTIR) spectroscopy showed that slower freezing rate and prolonged storage led to a significant decrease in the proportion of α-helices, and a notable increase in that of β-sheets and random coils. The gluten network was severely deteriorated by a slower freezing rate but was relatively intact in the −40 and −30 °C frozen dough samples.

The effects of vacuum mixing on the structural characteristics and physical properties of noodle dough were investigated using three leading Chinese wheat cultivars. Texture profile analysis showed that vacuum mixed doughs when sheeted all gave significantly higher levels of adhesiveness, elasticity, and chewiness than doughs from nonvacuum mixing. The cross section of sheeted dough mixed at 0.06 MPa had a more continuous and compact microstructure with fewer holes and gaps, as well as more even protein distribution at the surface, as evidenced by scanning electron microscopy and Fourier transform infrared microimaging. However, a higher degree of vacuum was detrimental to the developed network for weak dough. Dough mixed at 0.06 MPa had higher glutenin macropolymer content and lower free thiol group concentration compared with nonvacuum mixed doughs, which may largely relate to the improvement of dough texture. The development of the gluten network for weak gluten flour was more sensitive to the degree o...

Sensory quality and physico-chemical properties of 60 samples of white salted noodles, 23 egg noodles and 16 buckwheat noodles, collected from large-scale noodle manufacturers, were measured. The differences in quality among the three types of commercial dried Chinese noodles and relationships between the various quality parameters were investigated. Color and flavor were the main aspects of quality that varied among the commercial dried noodles. In texture profile analysis of the noodles after cooking, buckwheat noodles showed significantly lower measurements of hardness, cohesiveness, chewiness and resilience and these differences were confirmed by sensory tests. The color score of white salted noodles was positively associated with L* and negatively with a* (p

The Farinograph time-to-peak is an important wheat flour quality parameter. It is well-established that insoluble glutenins correlate with the strength of the gluten network and dough mixing time. To learn more about the physical changes at the mesoscopic level, dough samples were prepared in the Farinograph for study with diffusion wave spectroscopy. It was confirmed that a space-filling network was formed by wheat gluten proteins (mainly glutenin). At peak development (9.0 min) it was shown that the starch granules were confined in the gluten network. After the time-to-peak, dough resistance weakened, showing an increase of the starch granule movement. Kneading disrupts insoluble glutenin particles, the disrupted glutenin becomes part of the Sodium Dodecyl Sulfate (SDS)-extractable proteins. Both soluble and insoluble wheat protein extracts have been characterized by light scattering techniques. The results derived from light scattering of the wheat protein fractions: particle radii, apparent molar mass and geometrical shapes, suggests that the disrupted glutenin aggregate shape and glutenin size heterogeneity could be more important for gluten network bulk consistency, connectivity and resistance at dough peak, than the apparent molar mass of the solubilized glutenins, reaching a maximum after dough peak.