Wheat Flour Quality Research Articles

Predicting Rheological Properties of Wheat Dough from Flour Properties Using NIR Coupled with Artificial Neural Network

Highlights A multi-layered perceptron type artificial neural network (ANN) was developed to predict the farinograph properties of wheat dough. ANN models with two to four hidden layers were developed for each Farinograph response, i.e., water absorption, dough development time, and dough stability. Permutation importance and Shapley values analysis emphasized the significance of protein content in model prediction. The developed model would serve as a decision support tool for flour mill and bakery managers and would assist in adapting flour mill settings and modifying processing parameters in bakeries. Abstract. Farinograph analysis serves as the standard for determining the baking quality of wheat flour. It measures the water absorption (WA), dough development time (DDT), and stability (DS) of wheat dough. These characteristics depend on wheat flour properties such as protein content, moisture, ash, and falling number. Additionally, farinograph analysis is costly, time-consuming, and requires skilled personnel. Therefore, an artificial neural network (ANN) model was developed to predict the farinograph properties of wheat dough as a function of flour properties. The models were developed using data from 192 wheat samples. Multi-layer perceptron-type feed-forward ANN models with increasing complexity were developed for each response variable, i.e., ANN-WA, ANN-DDT, and ANN-DS, and model success was evaluated via mean squared error (MSE) and correlation coefficient (r). The optimal models had two to four hidden layers, each with five to sixty neurons, and exhibited the lowest MSE and highest r values. In terms of predictive performance, the models ANN-WA and ANN-DDT (r = 0.79) demonstrated superior performance when compared with ANN-DS (r = 0.63). A feature importance analysis was conducted to provide insight on variable contributions, underscoring the significance of flour protein content in the model’s prediction. The study explored the applicability of data-driven ANN models in predicting the rheological characteristics of dough. The developed models could serve as a decision support tool and aid millers in adjusting mill settings and bakers in modifying dough mixing based on dough rheology. Keywords: Artificial neural network, Dough rheology, Farinograph analysis, Milling, NIR.

Acidic water tempering and heat treatment, a hurdle approach to reduce wheat Salmonella load during tempering and its effects on flour quality

The cultivation and processing of wheat render it susceptible to microbial contamination from varied sources. Hence, pathogens such as Salmonella can contaminate wheat grains, which poses a food safety risk in wheat-based products. This risk is displayed by the incidence of foodborne illness outbreaks linked to Salmonella-contaminated wheat flour and flour-based products. The purpose of this study was to assess the effectiveness of combining acidic water and heat treatment in reducing the Salmonella load of hard red spring (HRS) wheat grains during tempering. Effective treatments were then evaluated for their effects on wheat flour quality. Tempering with sodium bisulfate (SBS), lactic acid (LA), and citric acid (CA) at 15% w/v alone reduced (p < 0.001) wheat Salmonella load by 3.15, 3.23, and 2.91 log CFU/g, respectively. Heat treatment (55 °C) reduced (p < 0.001) wheat Salmonellaload by 4.1 log CFU/g after 24 h of tempering. Combining both tempering and heat treatments resulted in a greater reduction in Salmonella load as non-detectable levels (<2 log CFU/g) of Salmonella in the wheat grains were obtained after 12 h of tempering with LA (15%) + heat. A similar result were achieved for both SBS (15%) + heat and CA (15%) + heat treatments after 18 h of tempering. Applying the combined treatments in HRS wheat grains resulted in comparable wheat flour baking (volume, texture, and crumb structure) and physicochemical properties (rheology and composition) relative to the control (tempering with water alone). The results from this study has the potential to be utilized for developing more effective methods for improving the food safety of wheat flour against Salmonella contamination.

Quality of Fortified Zea Mays L (Maize) and Triticum Durum (Wheat) Flours

Maize flour is obtained through the milling process and contributes about 20% energy and 15% protein. wheat flour is rich in starch (70 to75%), water (12 to 14%), protein (8 to16%), a small portion of non-starch polysaccharides (2 to 3%), lipids (2%) and ash (1%). This study aimed to evaluate the centesimal quality of maize and wheat flour. 8 samples of flour were evaluated, being 2 ((First Choice and Mpupu) and 6 of wheat flour (Faspão, Babita, Xiluva, Eagle, Pasta and Ntombi)). Moisture by loss on dissection at 105°C, ash by incineration, fat by goldfish method, protein by biuret method, fulling number by reading on mininfra grain analyzer Scan-T, gluten, wet and dry by glutomatic system, gluten index by centrifugation and fiber by enzymatic-gravimetric method were determined as quality parameters. The results showed fat content 0.61 to 1.59%, moisture 13.3 and 13.4%, fiber 0.22 to 0.38% and protein around 5.99 to 7.09% for the corn flours. Moisture ranging from 13.6 to 13.8%, protein from 10.30 to 11.22%, ash from 0.50 to 0.70%, water absorption from 58.23 to 59.73%, falling number 276 to 354s, gluten around 24 to 29.1%, gluten index from 0 to 95%, wet gluten from 28.46 to 29.80 and dry gluten ranging from 9.36 to 10.50%. No significant differences were observed among the wheat flour samples for moisture, protein, ash, water absorption and wet gluten. Significant differences were found for falling number (FN), gluten and dry gluten. There was sufficient evidence of compliance with the flour quality criteria.

Comparing bread-making properties of white and whole wheat flours from 64 different genotypes: A correlation analysis

Quality attributes of wheat and its flour strongly influence the processability, end-product performance, and consumer acceptability of wheat-based products. The quality of whole wheat flour (WWF) has been estimated using white flour (WF) methodologies, which raised concerns due to the uncertain correlations between WF and WWF. Strong correlations were identified between the WF and WWF for protein content and flour water absorption (r = 0.98 and 0.71, respectively), pasting properties of peak and final viscosity (r = 0.85 and 0.70, respectively), and the optimum mixing time determined by Mixograph (r = 0.83). In contrast, the bread volumes and water retention capacity were weakly correlated for WWF versus WF (r = 0.48 and 0.28, respectively). There was a negative relationship between the peak value of WF and the hardness of the white bread (r = −0.58), while it was not present for the WWF bread. This comparative evaluation of the dough rheological properties and bread-making performance of WF and WWF from 64 wheat genotypes is valuable to breeding programs, food processors, and millers, ultimately enhancing the efficiency and sustainability of wheat-related industries.

Effect of sweet potato flour on pasting, aggregation properties and dough quality of wheat flour

Sweet potato flour (SPF), as a functional substitute for wheat flour (WF), has gained popularity among consumers in the development of nutritious food products. However, the mechanism of SPF on gluten in dough remains unclear. Effects of SPF on the pasting characteristics, gluten aggregation properties, and the quality of dough were investigated. The results showed that SPF-WF exhibited low pasting properties, and pasting temperature increased by 22.35%–26.98%. SPF-WFs were lower in peak viscosity (62.57%–88.17%), trough viscosity (80.32%–96.67%), breakdown viscosity (11.58%–66.37%), final viscosity (70.72%–96.95%), setback viscosity (57.83%–97.33%), and peak time (16.26%–29.30%). Compared with WF dough, SPF-WF dough had higher hardness and lower elasticity. Microstructure images showed that SPF changed the pore size of the gluten network and caused starch to accumulate. SPF could accelerate gluten aggregation, decrease gluten network strength, and reduce aggregation energy, possibly due to the increase of disulfide bonds from 1.12% to 12.52% (P < 0.05). Moreover, SPF mediated medium molecular weight gluten as well as monomer gluten were polymerized into large molecular weights. In summary, SPF might mediate gluten aggregation and 10% substitution of SPF showed a significant level compared to others.

Wheat Flour Quality Assessment by Fundamental Non-Linear Rheological Methods: A Critical Review.

Wheat quality assessment involves physical, physicochemical, chemical, and sensory characterization of wheat kernels and the resulting wheat flour, dough, and bread. The physical tests conducted on wheat flour dough are mostly based on empirical methods. Empirical methods have been useful in industry and research to relate wheat flour quality to baking performance. However, these methods have the disadvantage of providing data in arbitrary units, which makes the fundamental interpretation of results difficult. Therefore, this review focuses on the use of fundamental rheological methods to determine wheat flour quality in terms of processing performance. During the transition from wheat flour to bread, wheat flour dough is mostly exposed to large deformations, and the quality of wheat flour determines its response to these large deformations and its baking quality. For this reason, this review only focuses on the application of fundamental rheological tests that are conducted in the non-linear viscoelastic region where wheat flour dough experiences large deformations.

Quantum agriculture and experimental detection of wheat flour quality using thermal image technology

Crop quality and productivity are the fundamental strategies of agricultural practice and technology; consequently, one of the priorities in agriculture is to be aware of new and innovative field experiments and production practices. The effectiveness of innovative practices and resources is influenced by a multitude of factors. This study aimed to propose a new quantum-based approach in agriculture using homoeopathic methodology which incorporates theories and concepts of quantum physics and employs a wave-based methodology for the functional measurement phase. A novel utilization of thermal imaging technology is suggested, wherein each pixel of the image indicates the wave parameters, frequency, or amplitude of wave, is proposed to analyse the functional information of the plant. The relationship between the new quantum-agriculture-based method and the functional characteristics of flour as measured by bio-photonic emissions was estimated, and the findings of this preliminary study on wheat flour are presented. Our preliminary results (i) confirm the superior performance of quantum agriculture (QA) based proposed soil and plant treatments, and (ii) suggest that quantitative analysis based on precise measurements of biophoton emission will provide a novel reliable tool for monitoring the quality of wheat in the future. Further investigations are required to replicate the results of this study under different environmental conditions. Additionally, incorporating comparative chemical analyses that would enhance our knowledge of the proposed agronomic practice.

Nutritional and Sensory Quality Attributes of Bread Produced from Wheat-Sprouted Finger Millet Flour

The current study was conducted to investigate the nutritional and sensory quality of wheat flour supplemented with sprouted finger millet flour in varying ratio to produce bread. Phytochemical screening of the ethanol extract of the flour samples confirmed the presence of many phytochemicals including flavonoids, phenols, terpenoids, alkaloids and tannins. The results of flavonoid, phenolic and alkaloid content of white wheat flour (WWF) are 1.34 ± 0.05 (mg QE/g), 2.25 ± 0.05 (mg GAE/g) and 1.26 ± 0.01 (%) respectively. The mean concentration of raw finger millet flour (RFF) : sprouted finger millet flour (SFF) for flavonoid, phenolic and alkaloid are 2.15 ± 0.15 mg QE/g : 2.87 ± 0.05 mg QE/), 4.24 ± 0.04 mg GAE/g : 5.10 ± 0.11 mg GAE/g and 2.56 ± 0.03 (%) : 2.58 ± 0.05 (%). The results of moisture content, ash and carbohydrate of the bread increases from 8.28-10.18 %, 1.70-2.55 %, and 69.30-70.21 % while crude protein, crude fat and crude fiber of the bread decreases from 12.80-11.20 %, 3.62-2.01 %, and 4.30-3.90 %. The sensory score results revealed that bread made with 100 % WWF (sample A) was most acceptable. The study has revealed that acceptable nutrient dense bread can be made from wheat and sprouted finger millet flour up to 30 % substitution.

Dough rheology, pasting property, and steamed bread quality of wheat flour as affected by the addition of sprouted wheat flour

ABSTRACT Grain sprouting poses a significant global challenge, especially for wheat. Nonetheless, recent investigators have unveiled numerous benefits of germination. In this study, we incorporated various proportions of sprouted wheat flour (SF) into wheat flour to produce sprouted wheat steamed bread (SWSB). The impact of SF on the quality of flour and SWSB was evaluated, resulting a development of GABA-enhanced, green-healthy SWSB. With increased addition of SF, the falling number, pasting viscosity, and dough stability time of flour exhibited significant decreases, whereas the gluten index initially increased and then decreased. The textural properties, such as hardness, chewiness, adhesion, springiness, and cohesion, exhibited varying degrees of fluctuation with increasing SF levels. The specific volume of SWSB was optimal at an SF concentration of 6% and the sensory score was highest at 2%. Lightness of SWSB was comparable to that of the control at 4% SF addition. C-cell images revealed that the fineness of the SWSB texture initially increased and then decreased with increasing SF levels. Overall, an SF concentration of 4% was found to be optimal for dough properties, color, texture characteristics and sensory quality, providing a theoretical foundation for industrial production and application.

Characterization of ash content in wheat flour using data fusion

Ash detection played an important role in wheat flour quality testing. In this work, we proposed a method for the ash content detection in wheat flour, which based on hyperspectral (HSI) method fused with terahertz (THz) technology. Standard Normal Variable Correction (SNV) and Multiple Scattering Correction (MSC) were used for the pretreatment of HSI and THz data. Moreover, feature wavelengths were extracted by the Successive Projections Algorithm (SPA) and Feature weighting algorithms (Relieff), respectively. Hierarchical Extreme Learning Machine (H-ELM) model were used for the analysis of two spectral data, which combined with data fusion strategy. The prediction coefficient of determination (r2) and the root mean square error of prediction (RMSEP) were employed to evaluate the performance of the model effectively. Results suggested that the model accuracy of data fusion was better than that of single spectrum model. Compared to other fused method, this model obtained better results at r2 = 0.989 and RMSEP = 0.015, which based on the SPA-selected HSI feature data fused with the Relieff-selected THz feature data. This study demonstrates that data fusion analysis offers a way to detect ash content in wheat flour, which based on HSI method and THz technology.

Rapid molecular assay for the evaluation of clove essential oil antifungal activity against wheat common bunt.

Common bunt of durum wheat (DW), Triticum turgidum L. ssp. durum (Desf.) Husn., is caused by the two closely related fungal species belonging to Tilletia genus (Tilletiales, Exobasidiomycetes, Ustilaginomycotina): Tilletia laevis Kühn (syn. T. foetida (Wallr.) Liro.) and T. caries (DC) Tul. (syn. T. tritici (Bjerk.) G. Winter). This is one of the most devastating diseases in wheat growing areas worldwide, causing considerable yield loss and reduction of wheat grains and flour quality. For these reasons, a fast, specific, sensitive, and cost-effective method for an early diagnosis of common bunt in wheat seedlings is urgent. Several molecular and serological methods were developed for diagnosis of common bunt in wheat seedlings but at late phenological stages (inflorescence) or based on conventional PCR amplification, with low sensitivity. In this study, a TaqMan Real Time PCR-based assay was developed for rapid diagnosis and quantification of T. laevis in young wheat seedlings, before tillering stage. This method, along with phenotypic analysis, was used to study conditions favoring pathogen infection and to evaluate the effectiveness of clove oil-based seed dressing in controlling the disease. The overall results showed that: i) the Real Time PCR assay was able to quantify T. laevis in young wheat seedlings after seed dressing by clove oil in different formulations, greatly reducing times of analysis. It showed high sensitivity, detecting up to 10 fg of pathogen DNA, specificity and robustness, allowing to directly analyze crude plant extracts and representing a useful tool to speed up the tests of genetic breeding for disease resistance; ii) temperature was a critical point for disease development when using wheat seeds contaminated by T. laevis spores; iii) at least one of the clove oil-based formulations tested was able to efficiently control wheat common bunt, suggesting that clove oil dressing could represent a promising tool for managing the disease, especially in sustainable farming.

Evaluation of Physico-Chemical and Microbiological Parameters of the Types of Wheat Flour Produced in Milling Company

Wheat flour is one of the most used ingredients in bakery products, based on its nutritional and technological properties. Also in recent years, with the increase in the variety of dough products, there has also been an increase in the types of wheat flour in a way that suits the needs of the market. This study aims to analyze the physico-chemical and microbiological characteristics of some types of wheat flour produced by a milling company, which are used for different purposes, such as: white flour, brown flour, whole meal flour, etc. In total, 6 wheat flour samples of different types were analyzed for: moisture, ash, gluten, acidity, water activity and total microbiological load. The results showed that the moisture content is below 14.5 % for all samples. The range of ash content varies from 0.46-1.29% and is different based on the type of flour, because it represents the total amount of minerals present in wheat flour. Acidity is the most used parameter to determine storage conditions and all samples had a low value of 0.09-0.21 %.The wet gluten content of the flour samples varies between the range of 27.3-34.4 %, the highest value of gluten was detected in brown flour. From the microbiological analyzes carried out, we see that the wheat flour samples analyzed result in a low microbial load. Based on the results of the analyzed samples, all types of wheat flour produced by this company have good quality in terms of the analyzed parameters. Usually, the quality of the final product depends on the quality of the raw ingredients. So, the study of the quality of wheat flour in terms of physico-chemical and microbiological parameters also means a higher quality and safety of bakery products.

The Effects of Insect Infestation on Stored Agricultural Products and the Quality of Food.

In this review article, we focus on the effects of insect pests on the quality of stored cereals and legume grains. The changes in the amino-acid content, the quality of proteins, carbohydrates, and lipids, and the technological characteristics of the raw materials when infested by specific insects are presented. The differences reported concerning the rate and kind of infestation effects are related to the trophic habits of the infesting insect species, the variation of the component distribution in the different species of grains, and the length of the storage period. For example, wheat germ and brans feeders such as Trogoderma granarium may cause a higher reduction in proteins than endosperm feeders such as Rhyzopertha dominica, since the germ and brans contain higher concentrations of proteins. Trogoderma granarium may also cause higher reduction in lipids than R. dominica in wheat, maize and sorghum, in which most of the lipids exist in the germ. Furthermore, infestation with insects such as Tribolium castaneum may downgrade the overall quality of wheat flour, by increasing the moisture content, the number of insect fragments, the color change, the concentration of uric acid, the microbial growth, and the prevalence of aflatoxins. Whenever possible, the significance of the insect infestation and the concomitant compositional alterations on human health are presented. It should be highlighted that understanding the impact of insect infestation on stored agricultural products and the quality of food will be crucial for the required food security in the future.

Evaluation of wheat kernel and flour quality as influenced by chlorine dioxide gas treatment

Chlorine dioxide (ClO2) gas, known for its high oxidation and penetration capacity, is a potential alternative fumigant to control stored-product insect pest population. In this study, hard red spring wheat (Triticum aestivum L.) kernels were exposed to varying levels of gaseous ClO2 concentrations (200, 300, 400, and 500 ppm, 1 ppm = 0.0027 mg/L at room condition) and held in a gas-tight bucket assembly for 24 h after achieving desired concentration. ClO2 treatment achieved complete insect mortality of lesser grain borer (Rhyzopertha dominica (Fabricius)) and highest adult progeny reduction at 500 ppm across all vial locations. Significant reduction (37.8–51.1%) in germination percentage resulted after exposure to 300–500 ppm. Flour lightness value significantly increased after kernel treatment at 200–500 ppm. The pH value of wheat flour was significantly reduced from 6.2 to 6.1 after 500 ppm treatment. Peak and final viscosities of wheat flour significantly decreased from 3303.7 to 3073.3 cP, and from 3515.0 to 3208.3 cP, respectively. No significant difference was observed in other investigated flour quality and functionality parameters, including falling number, trough viscosity, breakdown viscosity, starch damage, and Mixolab dough behavior properties. Overall, ClO2 treatment at 500 ppm is effective in killing adult lesser grain borers without negatively affecting wheat flour quality parameters.

Physicochemical and Rheological Characteristics of Commercial and Monovarietal Wheat Flours from Peru.

In Peru, wheat (Triticum aestivum L.) is one of the main resources in the food industry; however, due to its low harvested area, it is the second most imported cereal. The quality of wheat flour was studied to verify that it has desirable characteristics for the preparation of bakery products. The quality of commercial and monovarietal wheat flours was assessed by measuring their physicochemical and rheological parameters, as well as the gluten content and wheat protein fractions. Eight commercial wheat flours and four monovarietal wheat flours (Barba negra, Candeal, Espelta, and Duro) from Peru were evaluated. Commercial wheat flours presented significantly higher levels of protein and gluten index compared to monovarietal wheat flours (p < 0.05). Between both groups, no significant differences were observed in the content of wet and dry gluten. Interestingly, monovarietal wheat flours presented a higher percentage of gliadins and albumins/globulins, as well as lower levels of glutenin, compared to commercial wheat flours (p < 0.05). According to the logistic regression models, the baking strength (W) was the most important parameter to evaluate the quality of commercial and monovarietal wheat flours. Our results show that monovarietal wheat flours show a lower quality compared to commercial wheat flours.

Enhancing traceability of wheat quality through the supply chain.

With the growing global population, the need for food is expected to grow tremendously in the next few decades. One of the key tools to address such growing food demand is minimizing grain losses and optimizing food processing operations. Hence, several research studies are underway to reduce grain losses/degradation at the farm (upon harvest) and later during the milling and baking processes. However, less attention has been paid to changes in grain quality between harvest and milling. This paper aims to address this knowledge gap and discusses possible strategies for preserving grain quality (for Canadian wheat in particular) during unit operations at primary, process, or terminal elevators. To this end, the importance of wheat flour quality metrics is briefly described, followed by a discussion on the effect of grain properties on such quality parameters. This work also explores how drying, storage, blending, and cleaning, as some of the common post-harvest unit operations, could affect grain's end-product quality. Finally, an overview of the available techniques for grain quality monitoring is provided, followed by a discussion on existing gaps and potential solutions for quality traceability throughout the wheat supply chain.

Effects of tempering with phosphoric acid and potassium carbonate solutions on microbial load of wheat flour streams and quality properties of flour

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.

Study of the quality indicators of modern winter wheat varieties developed by the FSBSI ARC “Donskoy”

The current paper has presented a three-year estimation of 14 new winter bread wheat varieties, recently developed in the laboratory of half-intensive type of the FSBSI Agricultural Research Center “Donskoy”, according to such indicators as kernel hardness, grain nature weight, protein and gluten percentage in grain, IDK, SDS-sedimentation, flour strength, volume yield of bread from 100 g of flour and general baking assessment. The main way to improve the quality of winter bread wheat grain and flour is breeding, the development of varieties and samples with optimal values of these indicators. The purpose of the current study was to estimate current winter bread wheat varieties developed by the FSBSI Agricultural Research Center “Donskoy” according to the main quality indicators of grain and flour. Breeding for high flour-grinding and baking quality of grain has always been one of the priority areas for winter bread wheat breeding at the Agricultural Research Center “Donskoy”. There has been identified more than 14 % of protein in grain on average for all studied varieties in 2019 (14.14 %) and 2021 (14.10 %). The average value of gluten content in grain was at the level of 27.1 %. More than 28.0 % of gluten was found in such varieties as ‘Volnitsa’ (28.9 %), ‘Podarok Krymu’ (29.5 %) and ‘Zolotoy Kolos’ (28.9 %). According to a set of quality indicators, the studied genotypes belonged to the second and third quality classes according to GOST 9353-2016. According to the study results, there have been determined significant positive correlations between protein percentage and gluten content in grain (r = 0.71±0.19); volume yield of bread and general baking assessment (r = 0.95±0.05); gluten content and flour strength (r = 0.57±0.22); grain nature weight and SDS-sedimentation (r = 0.62±0.21); SDS-sedimentation and flour strength (r = 0.63±0.21).

Improving microbial quality of wheat flour using ethanol-water mixture as a tempering solution

Wheat flour may contain high microbial load due to the contamination of the wheat surface by different sources. This situation leads to outbreaks of foodborne diseases caused by wheat and wheat-based products. In this research, a novel application has been developed to reduce microbial contamination at the tempering stage of wheat. The effect of water with different concentrations of ethanol (10–90% (v/v)) against the microbial load of wheat was evaluated. Although 70% ethanol is widely used as an antimicrobial agent, the significant reduction in aerobic plate count (APC) and yeast-mold count (YMC) in wheat was 5.02 ± 0.20 log CFU/g and 5.96 ± 0.22 after tempering with 50% ethanol and above, respectively. The mechanism for the antimicrobial effect of 50% ethanol is that wheat absorbs water faster than ethanol, causing a rise in ethanol concentration on the grain surface over time. The chemical and technological properties of wheat flour were also investigated at 50% ethanol concentration, which showed the highest microbial reduction. This study shows adding ethanol at the tempering stage reduces the microbial load of wheat while maintaining some functional quality of the flour without requiring any treatments or time.

Radio-frequency treatment of medium-gluten wheat: effects of tempering moisture and treatment time on wheat quality.

Wheat and wheat flour are important raw materials of staple foods. Medium-gluten wheat is now the dominant wheat in China. In order to expand the application of medium-gluten wheat, radio-frequency (RF) technology was used to improve its quality. Effects of tempering moisture content (TMC) of wheat and RF treatment time on wheat quality were investigated. No evident change in protein content after RF treatment, but a reduction in wet gluten content of the sample with 10-18% TMC and RF treatment for 5 min, was observed. By contrast, protein content increased to 31.0% after RF treatment for 9 min in 14% TMC wheat, achieving the requirement of high-gluten wheat (≥30.0%). Thermodynamic and pasting properties indicated that RF treatment (14% TMC, 5 min) can alter the double-helical structure and pasting viscosities of flour. In addition, the results of textural analysis and sensory evaluation for Chinese steamed bread showed that RF treatment for 5 min with different TMC (10-18%) wheat could deteriorate wheat quality, while the wheat (14% TMC) treated with RF for 9 min had the best quality. RF treatment for 9 min can improve wheat quality when the TMC was 14%. The results are beneficial to the application of RF technology in wheat processing and improvement of wheat flour quality. © 2023 Society of Chemical Industry.