Search Results (65)

This study investigated the effects of roasting temperature (130 °C, 150 °C, 180 °C) and grinding fineness (10, 50, and 100 mesh) on the nutritional quality and physicochemical properties of high-resistant starch rice flour (Youtangdao 3). The results revealed that the process of whole-grain moist roasting, followed by milling and sieving, markedly enhanced the resistant starch (RS) content while concurrently reducing the fraction of rapidly digestible starch (RDS). Specifically, roasting at 130 °C with coarse grinding (R130-10) yielded the highest absolute RS content (27.45 g/100 g). However, for fine-particle fractions essential for food texture, roasting at 150 °C (R150-100) proved optimal by achieving the highest RS proportion within the starch matrix (89.36% by Englyst method). Structural analysis via X-ray diffraction (XRD) and scanning electron microscopy (SEM) revealed that roasting facilitated the reorganization of starch chains. This molecular rearrangement led to a pronounced increase in crystallinity and induced distinct morphological alterations within the granules. Furthermore, Rapid Visco Analyzer (RVA) profiling indicated a substantial decline in peak viscosity for all roasted samples, indicating a significant loss of pasting ability and an increase in structural rigidity. In conclusion, the combination of moderate roasting temperature and precise particle size control effectively optimizes the nutritional value of high-RS rice flour. These insights provide a theoretical basis for developing high-RS rice flour ingredients. Full article

Rice blast and bacterial blight are two major diseases that threaten rice production worldwide. Developing rice cultivars with both disease resistance and desirable grain quality is an important objective in modern rice breeding. In this study, R1179 carrying Pi2, Wx^b and Alk^b was crossed with IRBB7 carrying Xa7, Wx^b and Alk^b. Marker-assisted selection (MAS) was applied to an F₂ population of 1123 plants, and a line, G163, combining Pi2, Xa7, Wx^b and Alk^b, was developed. Disease resistance evaluation showed that G163 retained the blast resistance conferred by Pi2 and the bacterial blight resistance conferred by Xa7, exhibiting resistance to the tested isolates of both pathogens. Grain quality assessment indicated that G163 possessed favorable milling, appearance and eating quality traits. Rapid Visco Analyzer (RVA) profiling further indicated desirable starch pasting properties. In conclusion, the rice line G163 carrying Pi2, Xa7, Wx^b and Alk^b was successfully developed through MAS. The results provide a useful germplasm resource for breeding rice cultivars with combined disease resistance and desirable grain quality. Full article

To address the issues of rough mouthfeel and monotonous flavor in plant-based beverages, this study used extruded millet flour as the raw material, with non-inoculated millet paste as the control group, and investigated the effects of six different lactic acid bacteria starter culture formulations—including two single strains (Streptococcus salivarius subsp. thermophilus and Lactobacillus delbrueckii subsp. bulgaricus) and four multi-strain consortia (2, 4, 10, and 12 strains)—on the quality of fermented millet beverages. The structural properties of the fermented millet beverages were systematically evaluated through WHC (Water Holding Capacity), LF-NMR (Low-Field Nuclear Magnetic Resonance), RVA (Rapid Visco Analyzer), rheological properties, texture, particle size, and FTIR (Fourier Transform Infrared) analyses, covering aspects such as water status, pasting behavior, viscoelasticity, textural characteristics, particle distribution, and molecular structure. In combination with volatile flavor profiling and sensory evaluation, the fermentation performance and applicability of each starter formulation were comprehensively assessed. The results showed that MFB-2 exhibited the highest viscosity and gel strength, making it suitable for thick-set products, whereas MFB-10 and MFB-12 demonstrated superior gel stability, water-holding capacity, and shelf life. Sensory evaluation further corroborated the flavor analysis, with MFB-12 showing the best aroma and overall acceptability, alongside the greatest diversity of volatile compounds, while MFB-10 presented milder acidity and favorable sensory acceptability. Collectively, MFB-10 and MFB-12 were identified as the most promising starter culture formulations for industrial-scale production of fermented millet beverages. This study provides a scientific basis for tailoring starter culture complexity to modulate the texture and flavor of plant-based fermented products. Full article

High-amylose rice starch (HARS) complexation with fatty acids and emulsifiers was evaluated using differential scanning calorimetry (DSC), Rapid Visco Analyzer (RVA) pasting, X-ray diffraction (XRD), and in vitro digestibility. DSC confirmed amylose–lipid complex formation for both additive types, with emulsifiers more effective than fatty acids. Lysolecithin produced the largest amylose–lipid complex endotherm with no detectable uncomplexed melting peak. Complexation increased up to 2.5% (w/w) and then plateaued, accompanied by a reduced gelatinization endotherm. Fatty-acid effects depended on chain length and included overlapping melting from uncomplexed lipids; higher additive levels generally increased complex stability. RVA results indicated that emulsifiers, but not fatty acids, increased pasting temperature by approximately 10 °C and delayed pasting. Lysolecithin markedly reduced viscosity breakdown, suggesting restricted granule swelling due to stabilized complexes. Myristic acid and lysolecithin caused the greatest changes in thermal and pasting parameters. XRD patterns shifted from mixed A + V to predominantly V-type reflections, confirming V-amylose complex formation. In vitro digestion showed decreases of 7.5–15.8% in rapidly digestible starch and increases of 4.7–12.3% in slowly digestible starch and 2.4–39.5% in resistant starch, with the strongest effects for lysolecithin (and myristic acid). These results support emulsifier-assisted production of RS5 from HARS, enhancing its utilization. Full article

Foliar preparations are used in potato cultivation, and their use can affect starch properties, which are important for food production. Therefore, the aim of this study was to evaluate the effect of foliar application of preparations (biostimulants, fertilizers) during the growing season of potatoes (Solanum tuberosum L.), cultivar Concordia, on selected physicochemical, thermal, and rheological properties of starch. Eight commercial preparations (Basfoliar 12-4-6+S + ADOB PK (ADOB), Asahi SL, BlueN^®, Megafol^®, Quantis™, Qultivo, Rizoderma TSI, and Rizofos) were foliarly applied during the growing season. Potato starch was isolated using a laboratory method. Starch from potatoes grown without foliarly preparations served as a control sample. The research methodology included determination of amylose content and mean starch granule diameter. Thermodynamic characterization of gelatinization and retrogradation was performed using a DSC (differential scanning calorimeter), viscometric pasting characterization was performed with a Rapid Visco Analyzer (RVA), and flow curves were determined. A statistically significant effect of the type of foliar biostimulant/fertilizer applied on amylose content, starch grain size distribution, and rheological properties of the tested starches was observed. Amylose content ranged from 31.7% (BlueN) to 36.3% (ADOB). Starch from potatoes grown with ADOB had the largest grains, with the largest number of grains having a diameter >40 µm. The tested starches generally did not differ in terms of the onset, peak, and end temperatures of gelatinization determined using DSC. Similarly, slight differences were observed in the pasting temperature determined viscometrically. The RVA analysis showed that the highest maximum viscosity value was observed for starch obtained from the raw material stimulated with the Megafol preparation (3744 mPa·s), and the paste based on starch isolated from potatoes grown with the Asahi biostimulant was characterized by the highest rheological stability at 95 °C. The starch pastes obtained from the raw material stimulated with the Megafol and Quantis preparations were characterized by the lowest values of the consistency coefficient (15.7 Pa·sⁿ), and the control starch had the highest value of this parameter (21.7 Pa·sⁿ). Full article

Rapid Visco Analyzer (RVA) profile characteristics are important indicators of rice (Oryza sativa L.) eating quality. In this study, based on the high-density genetic linkage map constructed under the genetic background of Yuexianghzan (YXZ) and Shengbasimiao (SBSM), combined with the RVA profile characteristic data of recombinant inbred lines (RILs) grown in two environments, QTL scanning was performed using the ridge regression analysis method. A total of 59 QTLs associated with RVA profile characteristics were detected across 11 chromosomes in the two environments, with individual QTLs explaining 0.12% to 85.16% of the phenotypic variation. Moreover, 11 QTLs were repeatedly detected in two environments with large effects. The QTL located in the 1.44–1.85 Mb interval on chromosome 6 simultaneously controlled eight RVA profile characteristics and contained the cloned waxy (Wx) gene. Additionally, the intervals 20.58–20.70 Mb on chromosome 5 and 24.96–25.42 Mb on chromosome 8 were repeatedly mapped and influenced multiple RVA characteristics. Based on gene annotation information, a total of nine candidate genes (LOC_Os05g34730, LOC_Os05g34830, LOC_Os05g34854, LOC_Os06g03910, LOC_Os06g04200, LOC_Os06g42720, LOC_Os08g39830, LOC_Os08g39850, and LOC_Os08g39860) that directly or indirectly influence the starch synthesis pathway were identified. The results of this study lay a foundation for further map-based cloning of genes related to rice RVA profile characteristics and molecular design breeding. Full article

Wheat end-product quality results from complex interactions among protein, starch, and fiber, further complicated by genetic and environmental variability, especially in commercial samples composed of multiple varieties from diverse regions. Eighteen composite samples of hard red spring wheat (HRSW) were prepared from 755 field samples to simulate commercial grain blending. These composites were analyzed to evaluate the influence of flour composition on product quality. A wide range of flour compositional properties was analyzed and associated with dough and end-product quality traits, as measured by GlutoPeak, Rapid Visco Analyzer, Farinograph, Extensograph, Alveograph, and loaf baking. The results indicated that dough and bread quality are not determined by protein or gluten content alone, but that protein, starch and fiber composition and structural variations play a crucial role. Flours with higher proportions of high-molecular-weight glutenin (HMW-GS) fractions, particularly those rich in Bx and Ax subunits, exhibited greater dough resistance, mixing strength, and bread volume. In contrast, lower-performing samples were characterized by reduced HMW/LMW, polymeric/monomeric protein ratios, and HMW-Bx content. Multivariate modeling showed strong predictive performance for loaf volume (R² > 0.860) when protein, starch and fiber quality metrics were combined with protein content. These findings provide a data-driven framework for wheat flour classification and optimizing processing formulation. Full article

Arabinoxylans (AX) and their oligosaccharides (AXOS) have potential as functional ingredients. The emergence of biorefineries, leading to more Distillers Dried Grains with Solubles (DDGS) entering the animal feed market, encourages commercial production of AX products. Extracting AX from the two components of DDGS offers the opportunity to increase the biorefinery’s product portfolio and reduce costs. This paper explores AX extraction from solubles and wet grain, using a Gunt pilot-scale bioethanol plant to produce the two streams. After fermentation and distillation, solids were separated from the liquid to give Wet Distillers Grain (WDG), from which alkaline hydrogen peroxide extraction of water-unextractable AX (WUAX) was performed. The water-extractable AX (WEAX) was recovered from the solubles by ultrafiltration and ethanol precipitation. Both extracts were tested for suitability for AXOS production and characterised for their functionality. 10 kg of wheat yielded 3.2 litres of ethanol at 90% purity, 85 g of WUAX (51.6% purity, 110 kDa) and 92 g of WEAX (74.2% purity, 70 kDa). Enzymatic conversion of WEAX into oligosaccharides was 53%, whereas WUAX was unsusceptible to enzyme hydrolysis. Both AX fractions showed interactions with starch that could increase the shelf life of bakery products. AX-based products could be produced from a range of agricultural and biorefinery waste or low value streams, with the global market potentially > £1 billion per annum. Full article

Background/Objectives: FLOURY ENDOSPERM 2 (FLO2) is known to affect rice endosperm development and starch quality, yet its role in determining flour physicochemical behavior and endosperm structural integrity has not been quantitatively defined. This study aimed to elucidate how loss of FLO2 function alters starch organization and functional properties of rice flour. Methods: Two independent homozygous, T-DNA-free OsFLO2 knockout lines were generated in the japonica cultivar Dongjin using CRISPR/Cas9. Grain appearance was evaluated in mature seeds. Flour physicochemical properties were analyzed by Rapid Visco Analyzer (RVA) and differential scanning calorimetry (DSC). Amylopectin chain-length distribution was determined by isoamylase debranching followed by HPAEC-PAD, and endosperm microstructure was examined by scanning electron microscopy. Results: OsFLO2 mutants exhibited floury, opaque endosperms, with chalkiness increasing from 4.8% in the WT to 27–29%. RVA analysis showed a marked reduction in peak viscosity (1193 cP to 263–293 cP) and a decrease in pasting temperature (77.2 °C to 68.9–70.5 °C). DSC indicated a tendency toward reduced gelatinization enthalpy in the mutants. These changes were associated with a reduced proportion of short amylopectin chains (DP 6–12), decreased long chains (DP ≥ 37), and a relative increase in intermediate-long chains (DP 25–36), along with disrupted granule packing and a 1.33–1.36-fold increase in endosperm porosity. Conclusions: These results demonstrate that FLO2 plays an important role in maintaining the structural integrity of rice endosperm by harmonizing the microstructure of amylopectin with the thermal and gelatinization properties of starch. Full article

The objective of this study was to analyze the effect of different food proteins (wheat gluten, soy protein, whey protein, and ovalbumin), applied in different proportions, on the pasting and thermal properties of wheat starch using a Rapid Visco Analyzer (RVA) and Differential Scanning Calorimetry (DSC), enriching the RVA analysis with mathematical models for a deeper mechanistic understanding of the pasting behavior. Gluten and whey proteins significantly increased peak viscosity (up to +105% and +22%, respectively), while soy protein and ovalbumin decreased it (up to −16%). Conversely, the addition of all four proteins resulted in an increase in the starch pasting profile during the cooling period of the starch pastes (up to +95%). Additionally, the presence of all four proteins accelerated the starch paste formation process (0.2–0.9 min). Mathematical models showed that the addition of proteins accelerated both the viscosity decline phase (breakdown) immediately following the peak and the subsequent viscosity increase phase (setback), leading to the final viscosity. All proteins increased the gelatinization onset temperature, indicating restricted water availability for starch. Consequently, a decrease in gelatinization enthalpy was observed, most notably with ovalbumin (−28%) and whey protein (−24%). Conversely, the retrogradation characteristics showed no consistent pattern. These results offer valuable insights into managing the thermal stability of starch within diverse food applications (e.g., flour-based products) utilizing different protein sources. Full article

Starch granule size distribution plays a vital role in determining the physicochemical properties and processing quality of soft wheat. This study analyzed fourteen soft wheat varieties cultivated in the Huaihe River Basin, an agriculturally important but underrepresented region, to evaluate starch granule size distribution, pasting properties, and their interrelationship. The starch granules were categorized into four size classes, with the volume dominated by A-type granules (>10 μm), while numerically, the majority were <2.8 μm. Pasting characteristics measured by the Rapid Visco Analyzer revealed substantial variation among genotypes. Varieties with a higher proportion of A-type granules exhibited stronger pasting profiles, including higher peak and final viscosities, whereas those with more B-type granules showed lower values. These observations indicate a clear relationship between granule morphology and starch functionality. In the present study, there was a significant positive correlation between peak viscosity, final viscosity, and set-back viscosity. The volume % of granules > 10 μm showed a positive correlation with peak viscosity (r = 0.53 *), final viscosity (r = 0.57 *), and set-back (r = 0.53 *), while the volume percentage of granules < 10 μm was significantly negatively correlated with peak viscosity (r = −0.53 *), final viscosity (r = −0.57 *), and set-back (r = −0.53 *) value. It indicated that the higher the percentage of granules > 10 μm, the higher the peak viscosity, final viscosity, and set-back value in soft wheat grain. Full article

The incidence of duckweed (Lemna minor L.) outbreaks in paddy fields has increased in recent years, but how it impacts rice production is still under debate. This study assessed duckweed’s effects on rice yield and quality under different fertilizer regimes: organic fertilizer (OF), chemical fertilizer (CF), a mix (one-third OF and two-thirds CF based on nitrogen content, COF), and no fertilizer (NF) as a control. For each fertilizer regime, two duckweed treatments were applied: duckweed coverage (Duckweed) and no duckweed coverage (Control). A light wet–dry alternate irrigation method was used in the experimental field. Averaged across all fertilizer treatments, duckweed coverage in paddy fields increased grain yield by 8.3%, mainly due to increased panicle density. Duckweed coverage increased chalky grain percentage by 17.0% under NF, but decreased it by 33.7% under CF, with nonsignificant changes under COF and OF conditions. Similar fertilizer-by-duckweed interactions were also found for chalkiness degree, white degree, breakdown and setback values of the starch rapid visco analyzer (RVA) profile, palatability index, and protein and amino acid concentrations. Duckweed coverage decreased protein and amino acid concentrations but improved the taste of cooked rice under NF, while the opposite trend was observed under CF. Duckweed coverage significantly decreased copper and zinc concentrations in milled rice, which may aggravate the “hidden hunger” risk for rice consumers. Full article

Mirabilis expansa root (MER) is an Andean source of starch that could be considered a “lost crop” by the scarcity of its cultivation. Consequently, few studies have reported on its functional properties. To address this gap, we herein analyze and characterize the main components of MER and Mirabilis expansa starch (MES), measuring the water-absorption index (WAI), swelling power (SP), and water solubility index (WSI). We characterized the MES morphological and structural properties by using scanning electron microscopy (SEM). We also examined the starch pasting properties using a Rapid Visco Analyzer (RVA) to determine the peak viscosity (PV), final viscosity (FV), pasting temperature (PT), breakdown (BD), and setback (SB). The thermal properties were determined by differential scanning calorimetry (DSC), the crystallinity by X-ray diffraction, and the molecular structure by Fourier transform infrared spectrometry (FTIR). The main components in the MER and MES were carbohydrates and crude fiber. The MES appeared rich in amylopectin. The functional properties, the WAI, SP, and WSI, were dependent on temperature. The MES showed no morphological changes, a moderate gelatinization temperature, and C-type crystallinity. Finally, the FTIR spectrum presented the typical form for an unmodified starch. Based on these results, Mirabilis expansa may be considered a natural, non-conventional source of starch with potential applications in the food, chemical, and pharmaceutical industries. Full article

Ozone pollution decreases rice yield and quality in general, but how ozone stress changes grain-filling capacity is unclear. A chamber experiment was conducted to compare the effects of ozone exposure during the rice growth season on the grain-filling capacity and quality of spikelets located on the upper primary rachis (superior spikelets, SS) and the lower secondary rachis (inferior spikelets, IS). Ozone stress significantly decreased filled grain percentage by 41.4% and grain mass by 10.2% in IS, but had little effect on grain-filling capacity in SS. Consistent with the reduction in grain mass, ozone stress decreased grain volume, mainly due to reduced grain thickness, and IS was reduced more than SS. After removing the hull, brown rice obtained from ozone treatment exhibited higher proportions of immature and abnormal kernels, resulting in a substantially lower proportion of perfect kernels. Under ozone stress, the proportion of perfect kernels was only one-third in IS, compared with two-thirds in SS. Ozone stress affected the pasting properties of brown rice for both SS and IS, as shown by the decreased amylose content, and the increased maximum viscosity, minimum viscosity, final viscosity, setback, and peak time of the rapid visco analyzer profile. Out of fourteen traits related to nutritional quality of brown rice, only five showed significant increases under ozone stress, and they were the concentrations of albumin, prolamin, sulfur, copper, and manganese. The differential ozone responses between SS and IS were rather small for rice pasting properties and chemical compositions as shown by very few significant interactions between ozone and grain position. It is concluded that ozone stress during plant growth imposed more adverse effects on IS than SS in terms of grain-filling capacity and appearance quality, suggesting an enlarged asynchronous grain-filling pattern in rice panicles under ozone pollution. Strategies to improve the grain-filling capacity of IS are needed to mitigate ozone-induced damage to rice production. Full article

In this study, the effects of pregelatinization on the physicochemical properties of corn grits and the quality of cooked waxy corn wrapped in plant leaves were investigated. This investigation was conducted to address the issues of partial gelatinization and poor texture in corn grits when applied to food processing such as cooked waxy corn wrapped in plant leaves. After the corn grits were soaked at 55 °C, they were steamed for 30 min and dried at 45 °C (steam temperature maintained at 100 °C), reaching a gelatinization degree of 48.28%. The modified grits were characterized using Rapid Visco Analyzer (RVA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) to analyze pasting properties, retrogradation behavior, crystallinity, molecular structure, and morphology. The results showed that pregelatinization significantly reduced setback viscosity (from 274.83 to 154.52 mPa·s), crystallinity (from 11.12% to 3.62%), and retrogradation tendency while improving solubility, swelling power, and water-holding capacity. When used in cooked waxy corn wrapped in plant leaves, pregelatinized grits enhanced the gelatinization degree (96.11%), texture (reduced hardness by 19.49%, increased chewiness and cohesiveness), and moisture retention during storage. The findings demonstrate that pregelatinization optimizes starch functionality, mitigates retrogradation, and improves the overall quality of traditional corn-based foods, providing a practical approach for industrial applications. Full article