Protein content is an important quality trait in sorghum that influences breeding approaches, end-use applications, and market value. Influenced by genetic, agronomic, and environmental variability, sorghum is characterized by its wide variation in composition, which may also be evident in kernels from the same sample. This study developed and evaluated a method for a non-destructive and rapid prediction of protein content in individual sorghum kernels using single-kernel near-infrared spectroscopy (SKNIR). Applying different pre-processing techniques to the spectra collected from intact kernels, the calibration models were developed using partial least squares regression and the reference protein content values obtained from the LECO combustion method. The best model was obtained using multiplicative scatter correction as pre-processing, resulting in a standard error of prediction of 0.83% and a relative predictive determinant of 3.40. These were indicative of the good predictive ability of the model and the instrument to be applied in quality control and sorting applications. These results highlight the potential of SKNIR to capture the inter-kernel variability in sorghum protein content and enhance screening for grain quality in breeding and grain processing.

Baking tests are widely used as an important screening tool in bread wheat quality assessment but are time- and resource-intensive. This study evaluated the potential of machine learning models to predict key wheat baking quality traits, including bread loaf volume, crumb grain, texture, and overall baking quality, using a dataset of 359 hard winter (HW) wheat samples. A mutual information (MI) feature selection approach was integrated into a cross-validation pipeline to identify informative predictors from physicochemical and rheological properties. Model generalization was further assessed using an independent validation dataset comprising 26 HW lines from 2025. For loaf volume prediction, the gradient boosting model achieved cross-validation performance of R2 = 0.68 and RMSE = 56.1 cm3. MI feature selection reduced predictor redundancy while retaining much of the predictive performance. SHAP interpretation identified most influential predictors including total polymeric to monomeric protein ratio, sedimentation volume, extensograph energy, and alveograph elasticity index, highlighting the importance of both protein functionality and dough rheology. The results indicate that while individual predictors may help identify low-loaf-volume lines, accurate prediction of high-loaf-volume lines depends on interactions among multiple traits. These models provide a framework for data-driven screening in advanced wheat breeding lines.

Background and ObjectivesSorghum is the principal food source for smallholder farmers in Sub-Saharan Africa. Animal proteins are beyond economic reach, and only few food legumes are well-adapted in major sorghum-growing regions. Hence, sorghum serves as the primary source of protein and calories. However, the low digestibility of its proteins renders the communities vulnerable to protein malnutrition. Several factors, including genotypes and processing methods, have been shown to affect the digestibility of proteins in sorghum food products. The objective of this study was to investigate the impact of grain pretreatment on the protein digestibility of Ethiopian fermented flatbread.FindingsThe effect of four grain pretreatment processes: decortication, sprouting, parching, and untreated control was compared using four diverse sorghum genotypes milled to medium (2 mm) and fine (0.5 mm) particle sizes. The in-vitro protein digestibility (IVPD) was significantly lower in the parched samples compared to the unprocessed control, while sprouting significantly increased IVPD. Decortication appears to have no impact on IVPD. Finer particle size tended to enhance IVPD in all genotypes and for all pretreatement methods. The treatments had no significant effect on protein content except the sprouting consistently but marginally increased total protein.ConclusionsSprouting sorghum grains can significantly improve the protein digestibility of fermented breads. Given that it involves little cost, the process can be readily adopted by the local community, provided that they are educated about the impact of protein deficiency on the health and productivity of the community.Significance and NoveltyLow-cost grain pretreatment procedures such as sprouting can have a significant impact on the availability of nutrients, especially protein, the most limiting nutrient in smallholder communities. Combining the procedure with genetically enhanced varieties and improved cropping systems that integrate food legumes can significantly enhnace protein nutrition for smallholder farmers.

This study aimed to establish NIR spectroscopy models for fast predicting apparent amylose (AA) and total starch (TS) content in SSK. Reliable wet chemistry procedures for quantifying TS and AA in single sorghum kernel (SSK) were established, which achieved high accuracy with test errors below 1.0 %. The partial least squares (PLS) model with 2 latent variables (LVs) for AA prediction had coefficients of determination of 0.91 (R2cal) and 0.85 (R2cv), and root mean square errors (RMSE) of 1.90 % and 2.47 % for calibration (RMSEC) and cross-validation (RMSECV), respectively. It showed an R2pred of 0.83 and RMSE of 2.58 % for prediction (RMSEP) when validated with the independent validation set. The optimal SSK-TS NIR PLS calibration model was built from 187 calibration sorghum kernels with 10 LVs, which had a R2cal of 0.79, RMSEC of 2.76 % and RMSECV of 4.93 % and showed a R2pred of 0.72 and RMSEP of 3.19 % when applied to an independent validation set of 93 samples. Overall, this study successfully developed wet chemistry methods for measuring AA and TS contents in SSK and established NIR models for nondestructive prediction and sorting of sorghum kernels by their TS or AA content, serving as useful tools for sorghum breeding and application research.

Background and Objectives: Fundamentally it is important to understand starch granule initiation and deposition of starch molecules during the growth of granules. The objective of this study was to investigate the morphology, composition, and structure of starches in sorghum from fifth day post-anthesis (DPA) until the maturity (25 DPA). Findings: The minimal size of sorghum starch for showing Maltese cross was 4 mu m. The average size of starches on 5 DPA was 3.2 mu m, and most starches did not exhibit Maltese cross. Amylose content was low (13.0%) on 5 DPA and increased to 31% on 25 DPA. The size of amylose was long with a peak at DP 1771 on 5 DPA and changed during the starch biosynthesis. The short-chain amylopectin proportion significantly increased on 25 DPA. Conclusions: The low amylose content and high proportion of long-chain amylose might be favorable for the initial sorghum starch formation. The starch polymers were less radially oriented in the primary starches. Amylopectin in the periphery of a large sorghum starch was more branched than that of the inner part. Significance and Novelty: The variations in the amylose length distributions and orientation of starch polymers provide new information on starch biosynthesis.

Waxy sorghum seeds, defined by reduced amylose content in starch, offer the potential for improving grain quality in food and industrial applications. While waxy endosperms arising from a nonfunctional waxy (wx) allele leading to the absence of granule-bound starch synthase enzyme have been identified in sorghum, their broader effects on seed development and grain quality remain inadequately understood. To address this gap, we identified a novel wx loss-of-function allele, "wxe" in the mutant population of the sorghum reference genome line BTx623. Beyond reduced amylose content, wxe exhibited increased kernel hardness, elevated protein content, reduced endosperm-to-germ ratio, and decreased kernel weight compared to the wild-type. Integrating transcriptomic, metabolomic, and seed chemistry analyses revealed coordinated regulatory changes during seed development due to disrupted amylose synthesis. This included altered starch granule structure, enhanced lipid profiles, and reduced carbohydrate content. Differentially expressed genes and transcription factors related to starch metabolism provided insights into the regulatory mechanisms. Furthermore, metabolic profiling showed significant changes in the accumulation of compounds influencing flavor and nutritional properties. This study enhances our understanding of the molecular coordination of sorghum seed development and provides new insights into regulating seed development.

Conventional bioethanol production from starch-based crops involves high-temperature cooking, which is energy-intensive and degrades the protein quality of distiller's grains (DG), a valuable co-product. This study addresses the critical gap of reducing the energy demand and protein degradation by comparing conventional high-temperature processing with granular starch hydrolyzing enzyme (GSHE) fermentation at low temperatures. Specifically, the novelty lies in optimizing partial starch swelling treatments (50 degrees C, 60 degrees C, 70 degrees C) to enhance ethanol yields while preserving DG protein quality. Using sorghum varieties (normal and waxy) as a model system, we conducted experiments combining low- temperature starch swelling and GSHE fermentation to evaluate their impacts on ethanol yield and protein properties. Waxy sorghum exhibited higher ethanol fermentation efficiency than normal sorghum. Partial starch swelling significantly improved ethanol yield without compromising DG protein quality. GSHE fermentation with starch swelling at 70 degrees C for 30 min achieved the highest ethanol concentration (12.02 % v/v) and yield (92.74 %) for waxy sorghum. Protein digestibility remained high for both waxy (85.39 %) and normal sorghum (85.21 %) even at higher swelling temperatures. Surface hydrophobicity of DG proteins increased with temperature, particularly at 95 degrees C during conventional processing. Notably, partial starch swelling improved the lightness (L* values) of sorghum proteins, indicating better quality. Molecular characterization further revealed the specific effects of processing on protein properties. This research highlights the potential of low-temperature starch swelling combined with GSHE fermentation to enhance ethanol production efficiency and protein quality in DG, offering a sustainable alternative to conventional bioethanol processes.

Background and Objectives Waxy sorghum contains essentially only amylopectin in its endosperm starch and has unique properties that could be potentially used in value-added food ingredients as an effective thickener. The objectives of this study were to develop an efficient process for isolating starch from waxy sorghum grains using alkaline protease and to compare the properties of starches isolated by enzymatic methods with that of starches isolated by the traditional wet milling method. Two starch isolation methods based on protease treatment were developed using whole and decorticated waxy sorghum grains. Those two methods were compared with a traditional wet milling method to evaluate the efficiency of the isolation process and properties of the starches isolated, including starch recovery, yield, residual protein, ash content, damaged starch content, color, as well as pasting and thermal properties.Findings Starch recovery showed no statistical differences among the three methods, and all isolated starches exhibited desired purity regardless of the method employed. However, enzymatic treatment methods not only produced starches with lower residual protein (0.18%-0.22%) but also resulted in significantly greater peak (1992-2023 cP), breakdown (1123-1172 cP), and setback viscosities (275-355 cP) compared with the waxy sorghum starch isolated by the wet milling. The starches isolated by wet milling and enzymatic treatment of decorticated sorghum exhibited similar onset and peak gelatinization temperatures, while both methods produced starches with better color quality (higher L*, lower b*) compared to starches isolated from whole sorghum using the enzymatic treatment.Conclusion Enzymatic treatment of decorticated sorghum could be used as an effective method for starch isolation at the laboratory scale, with promising potential for application in industrial-scale processes.Significance and Novelty An efficient process was developed for isolating waxy sorghum starch, providing a sustainable alternative to wet milling by balancing processing efficiency and starch quality while maintaining high starch recovery.

Amylose content plays an important role in functional and nutritional properties of starches and flours, yet different amylose contents are often reported from different analytical methods for the same sample. The objectives of this study were to compare the measured amylose content of sorghum starches and flours by four different methods [iodine colorimetric, differential scanning calorimetry (DSC), Concanavalin A (Con A), and gel-permeation chromatography (GPC) methods], and determine molecular structure of sorghum starches by analyzing molecular size distribution of the fractions separated by Con A and 1-butanol/isoamyl alcohol as well as the starches before and after debranching. Amylose contents of normal sorghum starches and flours measured by the colorimetric, DSC and GPC methods were similar. However, amylose content was ∼7 % lower when determined by the Con A method. The GPC profile of the debranched Con A precipitation fraction revealed amylose-like long chains with clustered short chains that co-precipitated together with amylopectin by Con A, thus excluded in amylose quantification. The commercial potato amylose product had a smaller molecular size, and short branches compared with the lab-isolated potato amylose and resulted in different iodine-binding capacity and complexing with lipid, affecting the measurement of amylose by colorimetric and DSC methods.

Sorghum (Sorghum bicolor L. Moench), characterized by substantial genetic diversity, encompasses some lines rich in health-promoting polyphenols. Laboratory studies have demonstrated anticancer properties of sorghum phenolics; however, their presence may impact nutritional factors, such as digestible starch. The objective of this study was to determine the effects of pH and high-moisture heating on starch digestibility, phenolic profile, and anticancer activity in sorghum. High Phenolic sorghum flour line SC84 was combined with buffer solutions (pH 3, 4, 5, 7, and 8) and heated for 0, 10, 30, 60, or 120 min. Starch digestibility was assessed using the K-DSTRS kit from Megazyme. Changes in phenolic composition were analyzed using total phenolic content (TPC) and condensed tannin content (CTC) assays coupled with reversed phase high performance liquid chromatography (RP-HPLC) analysis. Anticancer potential against human colorectal cancer cells (HCT116 and SW480) was determined though cell viability assay. Results indicated a significant increase in total starch digestibility of sample after heating. Heating samples for 10 min did not significantly reduce TPC of samples. However, CTC was significantly reduced with heating time, while pH exhibited no significant effect on CTC. The measured 3-deoxyanthocyanidins experienced a significant decrease (p < 0.0001), while certain flavonoids increased significantly (p < 0.05) after heating for 30 min or longer. Notably, the 10 min heating duration minimally affected anticancer activity, whereas longer heat times diminished extract efficacy against human colorectal cancer cells. Alkaline pH levels significantly decreased anticancer activity, regardless of heating time. Importantly, heating sorghum for 10 min improved starch digestibility with minimal compromise to potential health benefits. These findings suggest promising implications for the development of high-phenolic sorghum products, and provide valuable insights to guide forthcoming animal and clinical studies. The demonstrated impact of wet-heating on increased starch digestibility, coupled with the preservation of phenolic content and bioactivity, underscores the potential of incorporating high-phenolic sorghum lines in future functional food formulations.

Wheat bran possesses diverse nutritional and functional properties. In this study, wheat bran aqueous extract (WBE) was produced and thoroughly characterized as a functional ingredient and improver for bakery application. The WBE contained 50.3% total carbohydrate, 24.5% protein, 13.0% ash, 6.7% soluble fiber, 2.9% insoluble fiber, and 0.5% β-glucan. Notably, adding 7.5% WBE significantly increased the bread-specific volume to 4.84 cm3/g, compared with the control of 4.18 cm3/g. Adding WBE also resulted in a remarkable improvement in dough properties. The WBE-enriched dough showed increased peak, setback, breakdown, and final viscosities, along with higher storage and loss modulus. Scanning electron microscopy analysis further revealed that the WBE promoted the aggregation of protein and starch within the dough. The extractable gliadin to glutenin ratio increased with 5 and 7.5% WBE additions, compared with the control and 2.5% WBE addition. WBE did not significantly alter the starch gelatinization temperature or dough extension properties. These findings demonstrate that the inclusion of WBE in wheat flour is a promising approach for producing high-quality bread that is enriched with dietary fiber and protein.

Near infrared (NIR) spectroscopy is widely used for evaluating quality traits of cereal grains. For evaluating protein content of intact sorghum grains, parallel NIR calibrations were developed using an established benchtop instrumentation (Perten DA-7250) as a baseline to test the efficacy of an adaptive handheld instrument (VIAVI MicroNIR OnSite-W). Spectra were collected from 59 grain samples using both instruments at the same time. Cross-validated calibration models were validated with 33 test samples. The selected calibration model for DA-7250 with a coefficient of determination (R2) = 0.98 and a root mean square error of cross validation (RMSECV) = 0.41% predicted the protein content of a test set with R2 = 0.94, root mean square error of prediction (RMSEP) = 0.52% with a ratio of performance to deviation (RPD) of 4.13. The selected model for the MicroNIR with R2 = 0.95 and RMSECV = 0.62% predicted the protein content of the test set with R2 = 0.87, RMSEP = 0.76% with an RPD of 2.74. In comparison, the performance of the DA-7250 was better than the MicroNIR, however, the performance of the MicroNIR was also acceptable for screening intact sorghum grain protein levels. Therefore, the MicroNIR instrument may be used as a potential tool for screening sorghum samples where benchtop instruments are not appropriate such as for screening samples in the field or as a less expensive option compared with benchtop instruments.

Background and ObjectiveDough mixing properties are crucial in determining the usability of wheat flour. Currently, many industrial sourced chemicals are used as additives to improve the mixing stability of dough. This study aims to evaluate the effect of adding chickpea flour on mixing tolerance and dough strength improvement based on 20 different wheat genotypes. The effects of different types (i.e., kabuli and desi) and amounts (1.5%, 3.75%, 7.5%, 15%, and 30%, w/w) of chickpea flours and kabuli chickpea fractions (7.5%) were further studied. Mixograph, dough strength and extensibility, and baking test of selected treatments were performed. FindingsIncorporating chickpea flour at a level of 7.5% (w/w flour basis) or lower significantly improved (p < .05) the mixing stability and dough strength of different wheat flours. Adding the insoluble fraction of the chickpea flour resulted in better stability and dough strength compared to other fractions, while adding the soluble fraction of chickpea flour weakened the dough. At the optimum incorporation level (7.5%) or lower, the inclusion of chickpea flour did not negatively alter the physical (bread volume), texture (hardness), or taste attributes of the bread. ConclusionThe results demonstrate that adding chickpea flour can improve dough mixing properties, particularly for weak/normal wheat flour, without compromising the quality of bread. The optimal chickpea flour incorporation level in refined wheat flour is 7.5%. Chickpea flour incorporation could also assist bakers in case of overmixing the dough. Significance and NoveltyThis study portrays the use of natural ingredients to improve dough mixing properties, providing bakers and scientific community with natural alternatives to enhance wheat flour mixing properties while improving the quality and nutrition of the flour as chickpea is a protein-rich legume.

Foods from grains and grain-derived ingredients are among the most important energy and nutrient source for humans [...]

Proteins exist in numerous spatial arrangements and are stabilized by various inter- and intra-molecular forces. The objectives of this study were to investigate the functional properties of pea protein isolate in terms of water/oil holding capacity, emulsifying and foaming properties, solubility, and gelation by modulating protein covalent and non-covalent interactions with specific denaturants/modifiers and to understand the physicochemical characteristics (e.g., free amino group content, free sulfhydryl group content, surface hydrophobicity, SDS-PAGE profile, secondary structures) of the unfolded pea proteins that are responsible for the functional changes. All the denatured proteins possessed significantly increased solubility. Both urea and SDS unfolded proteins had significantly higher water holding capacity and oil holding capacity of up to 5.01 and 5.09 g H2O/g, and 3.06 and 2.84 g oil/g compared with the control pea protein (4.12 g H2O/g and 1.29 g oil/g), respectively. The proteins unfolded with urea or SDS also showed improved emulsification properties. The trypsin hydrolyzed protein exhibited the highest foaming capacity and better gelation properties among all the treatments. Principal component analysis indicated strong associations between protein functional and physicochemical properties and molecular interactions. This study provides useful fundamental knowledge in tailoring protein structures in order to enhance its functionalities and broaden the food applications.

HighlightsPrediction models for high accuracy measurement of single kernel (SK) moisture content (MC) and protein content (PC) were developed using near-infrared reflectance (NIR) spectroscopy.USDA-ARS tube SKNIR instrument sorted individual kernels based on single kernel protein content (SKPC) which enabled determining the effect of three PC levels within a popcorn variety on popping performance.Variety, MC, and PC affected popping expansion, ball rate, and number of unpopped/half-popped kernels.Within popcorn variety, increased PC significantly increased expansion and reduced number of unpopped kernels but did not affect ball rate of popped flakes.The ability to sort single kernels for specific quality parameter, such as PC, is an important and useful tool for popcorn breeders and processors to meet consumer demand for specialized products.Abstract. The increasing demand for specialized high-quality popcorn products necessitates that the popcorn industry continuously identify quality parameters that can be improved through plant breeding or manipulated or sorted for improved end-products. Relationships between protein content (PC) and popping performance (expansion, ball rate, and number of unpopped kernels) has been investigated but there has been no research on segregating individual kernels from within the same variety for specific PC ranges, which may eliminate possible interference from some underlying variety- or production-related effects. Prediction models for determination of single kernel moisture content (MC) and PC were developed for the USDA-ARS tube single kernel near infrared reflectance (SKNIR) instrument. Both parameters were predicted with high accuracies for independent validations. MC showed an R2 of 0.94 and SEP of 0.25% while PC had R2 of 0.92 and SEP of 0.35%. Popping tests showed that increased kernel PC significantly (p<0.05) increased expansion and lowered the number of unpopped kernels but had no effect on the ball rate of popped flakes. Thus, applications that require increased overall expansion and reduced number of unpopped kernels may be addressed by the removal of low protein popcorn kernels from a popcorn lot, which can be achieved using an automated SKNIR technique. The SKNIR technique also provides a means for plant breeders to work on targeted/specific PC or PC range based on the single kernel selection. Keywords: Ball rate, Expansion, Mushroom popcorn, NIR spectroscopy, Popcorn quality, Single kernel, Unpopped kernels.

Background and objectives Wheat (Triticum aestivum L.) is highly vulnerable to heat stress during sensitive growth and developmental stages, including grain-filling. The impact of high daytime heat stress on wheat yield and quality losses has been extensively investigated, while information related to high night-time temperature (HNT) is limited. The major objective was to ascertain the changes in wheat grain macro- and micro-nutrient composition and yield-related parameters on exposure to HNT during grain-filling. Twelve diverse genotypes were grown in field-based custom-built heat tents that allowed natural light and temperature conditions during the day and imposed stress overnight. Findings The field-tents imposed a 3.2 degrees C higher night-time temperature compared to ambient conditions throughout the grain-filling period. HNT stress reduced 200 grain weight by 1.9%, grain yield by 3.1%, seed starch content by 2.5%, and seed protein content by 3.6% per degrees C increase in HNT. Conclusions HNT had significant negative effect on grain macro- and micro-nutrient content. However, starch and protein concentrations were differentially correlated with grain nutrients, with starch negatively correlated with many of the micronutrients under control and HNT. Significance and novelty This negative correlation highlights the imperative balance of seed micronutrient composition that needs to be maintained as efforts are intensified to enhance grain yield under favorable and warming environments.

In vitro digestibility of starch in sorghum grains differing in endosperm hardness and flour particle size was investigated. The starch digestibility increased as the particle size of flour decreased, but no clear trend was observed in digestibility of starch in sorghum flours milled from grains with different hardness. The protein matrix affected the digestion of starch. The pH value (2.0 vs. 1.3) was a critical factor affecting protein digestion. Optimum pH (pH 2.0 for pepsin) digested more protein, resulting in a greater digestion of starch. Resistant starch (RS) content was 8.5-26.3% in isolated sorghum starch but higher (10.6-29.5%) in sorghum flours. Protein digestibility decreased after cooking while starch digestibility increased compared to native sorghum flours; disulfide bonds formed between protein molecules. RS content of cooked sorghum flour was much higher without pepsin treatment (16.93-23.99%) than that of cooked sorghum flour with pepsin treatment (4.86-12.53%).

近年来单一税在许多国家及理论界受到青睐,但其在税制改革实践中并未大量扩散,而且已有10多个国家退出了单一税行列.那么,单一税能够成为世界性个人所得税改革的蓝图吗?事实上,这取决于改革细节和现实环境两个相互依存的方面.研究发现,各国单一税呈现一定程度的趋同性,但税制模式不统一;单一税改革不是孤立的,通常涉及整个税收体系的配合性改革;单一税改革受到诸如市场经济转轨、执政理念、财政赤字、收入分配差距、国际税收竞争以及国际组织等因素的综合影响,是时代的产物和动态的理性选择.因此,单一税难以成为世界性个人所得税改革的蓝图.然而"低税率、宽税基、简税制"的单一税思想,可为我国个人所得税的改革提供借鉴和参考.