Search Results (645)

Sparganium stoloniferum tubers (SL), known medicinally as Sparganii Rhizoma, are commonly considered superior at the winter-harvest stage, when they show the traditional quality traits of heavy weight and firm texture. However, the developmental basis of this quality phenotype remains insufficiently understood. This study aimed to determine how tissue organization, cell-wall architecture, starch deposition, and related transcriptional patterns are associated with winter-harvest quality in SL. By comparing SL at different developmental stages, we found that maturation was accompanied by reduced moisture content, increased tuber density, higher parenchyma cell density, progressive cell-wall thickening, and marked starch accumulation. Laser scanning confocal microscopy (LSCM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) observations further revealed thickened multilamellar cell walls and abundant clustered or compound-like starch bodies in mature SL. Starch isolated from mature SL displayed an A-type crystalline pattern, short-range order, and high gelatinization and pasting temperatures, indicating an ordered and thermally stable starch matrix. Cell-wall Fourier-transform infrared spectroscopy (FTIR) and solid-state nuclear magnetic resonance (NMR) analyses showed a predominantly polysaccharide-rich framework with subtle maturation-associated changes in aromatic- and methoxy-associated wall signals. Transcript-guided pathway analysis, supported by reverse transcription quantitative polymerase chain reaction (RT–qPCR)validation, suggested developmental shifts in carbohydrate metabolism, lipid-related metabolism, and gibberellin-associated transcriptional patterns. Together, these findings indicate that winter-harvest quality in SL is associated with coordinated tissue consolidation, cell-wall maturation, starch deposition, and transcriptional reprogramming, providing a structural and molecular framework for understanding the traditional firm-texture trait of S. stoloniferum. Full article

In this study, we systematically investigated the concentration-dependent effects of peptides derived from sour jujube kernel peptide (SJKP) on the multiscale structure, physicochemical properties, in vitro digestibility, and antioxidant activity of a complex formed between pea starch (PS) and SJKP. At an optimal SJKP content of 7.5% (w/w, based on starch dry basis), the slowly digestible starch (SDS) and resistant starch (RS) increased by 23.00% and 49.80%, respectively. X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FT–IR) verified the formation of complexes and enhanced the short-range structural order of starch. Thermal analysis showed that the gelatinization enthalpy increased to 11.73 J/g, accompanied by an elevated gelatinization temperature and improved thermal stability. Conversely, at 15% SJKP content, RDS rebounded to 58.3% due to phase separation and structural collapse of the starch matrix. Intermolecular force analysis revealed that hydrogen bonding dominated at SJKP concentrations ≤ 7.5%, while hydrophobic interactions prevailed at concentrations ≥ 10%. SJKP incorporation also endowed the complexes with antioxidant capacity. These findings illustrate that SJKP interacts with pea starch via non-covalent bonds, forming a mixed gel network. Moderate SJKP levels can effectively modulate starch digestibility and functionality via regulating intermolecular interactions and multi-scale structure, offering promising potential for developing low-glycemic index (LGI) functional foods, including baked snacks, nutritional beverages, and diabetic-specific staple foods. Full article

This study investigated the effect of pre-cooking level of germinated highland barley pulp on the staling properties and digestibility of pre-packaged barbecued pork buns during refrigerated storage (0–9 days). The addition of barley pulp significantly delayed quality deterioration, resulting in a decreased specific volume (up to 20%) and an increased hardness (up to 71.76%) across all samples. Furthermore, it effectively inhibited the rise in starch short-range order, as evidenced by a decreased FTIR ratio of 1047/1022 cm⁻¹, and retarded the conformational transition between protein α-helix and β-sheet structures. When the gelatinization degree increased to 91.22%, rapidly digestible starch (RDS) decreased significantly while resistant starch (RS) increased. The sauce infiltration layer exhibited a higher maximum RS (23.23%) than the inner crumb (16.52%). The Glycemic Index (GI) was significantly reduced, with the lowest values observed in the BJ60 group (53.22 for the sauce infiltration layer and 60.37 for the inner crumb). α-Amylase inhibition was also enhanced with increasing gelatinization degrees. Significant correlations were found between starch structural parameters and digestibility. These results demonstrate that incorporating germinated highland barley pulp is a feasible strategy to simultaneously improve the shelf-life and nutritional quality of steamed buns. Full article

Oat starch, β-glucan, and protein are the primary components in oats with high nutritional value, and the interactions among these three constituents markedly influence the starch properties. High hydrostatic pressure (HHP), recognized as a non-thermal processing technique, is primarily employed for the modification of starch and protein in food processing applications. This study aimed to elucidate the interactions among oat β-glucan, protein, and oat starch under 300 MPa HHP treatment and their effects on starch properties. The results showed that at ambient pressure, β-glucan and protein mainly restricted starch swelling and gelatinization through water competition, leading to reductions in pasting viscosity, gelatinization enthalpy, and relative crystallinity. In contrast, HHP treatment significantly enhanced the intermolecular interactions among the three components, thereby improving the freeze–thaw stability, gel elasticity, short-range ordered structure, and thermal stability of the composite system. The study demonstrates that HHP modifies the physicochemical properties of starch by intensifying interactions among its components, providing a theoretical basis and strategy for the development of novel functional starch-based foods using HHP technology. 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

Rice eating quality is a core determinant of consumer preference and commercial value. Although it is chemically determined by the accumulation and distribution of the substances in rice seeds, the comprehensive physicochemical basis underlying this trait in japonica rice remains insufficiently clarified. To identify the key physicochemical indicators that predict and regulate japonica rice eating quality, the taste value of 59 japonica rice varieties was evaluated, and the protein content (PC), apparent amylose content (AAC), starch pasting properties, gelatinization characteristics, and textural attributes were systematically measured. The results indicated that japonica rice has an average taste value of 72.0 with a range between 54.0 and 87.8. The taste value was significantly negatively correlated with PC, onset (To), peak (Tp) and conclusion (Tc) gelatinization temperatures, but was significantly positively correlated with appearance score, mouthfeel score, hot paste viscosity (HPV), and cool paste viscosity (CPV). PCA further indicated that AAC, HPV, CPV, peak viscosity (PV), and setback value (SB) were the major contributors to the first principal component, explaining 38.5% of the total variation. Stepwise regression analysis showed that the best regression equation for predicting taste value was: Taste value = 142.526 − 5.226 PC − 0.425 To (R² = 0.455; p < 0.001), confirming PC and To as the core parameters accounting for 45.5% of the taste value variation. Path analysis further indicated that PC and To affected japonica rice eating quality through direct and indirect pathways. These findings suggest that low PC, low gelatinization temperature, high HPV, and high CPV can serve as good physicochemical indicators for the breeding of high-eating-quality japonica rice. Full article

Durian (Durio zibethinus Murray) seeds, an underutilized by-product of durian processing, were upcycled into functional flours to elucidate how varietal origin and processing govern structure–function relationships. Durian seed flours from local Bang Nara (L) and Monthong (M) varieties were prepared using three methods: native durian seed flour (NDSF; control), boiled durian seed flour (BDSF), and hydrated durian seed flour (HDSF), and benchmarked against commercial mung bean flour (MBF) and almond flour (ALF). Proximate composition, total phenolic content (TPC) and DPPH^•- scavenging activity, structural characteristics (Fourier transform infrared, FTIR; X-ray diffraction, XRD), thermal behavior, and microstructure were assessed alongside functional properties including water/oil absorption, emulsion performance, and gelation. M flours contained higher protein (8.46–10.73%), dietary fiber (6.26–9.37%), ash (3.59–4.38%), TPC (53.17–87.40 mg gallic acid equivalent/g), and DPPH^•- scavenging activity (92.39–94.54%) than L flours, whereas L flours had higher carbohydrate content (78.87–82.54%) than M flours (68.32–72.21%). Crude fat remained below 1% across all samples. FTIR and XRD profiles were comparable to MBF, confirming starch-based similarities, but distinct differences in color, bulk density, crystallinity, gelatinization behavior, and granule morphology reflected processing-driven structural modification. Functionally, NDSF exhibited the highest water absorption capacity (4.28 g/g); all durian seed flours showed low oil absorption (0.58–0.88 g/g) and gelation at 10–12%. Most samples demonstrated good emulsion activity and stability, except HDSF. Overall, NDSF and BDSF provided the best balance of yield, hydration capacity, and structural stability, demonstrating that both variety and processing determine the performance of upcycled durian seed flours. These findings support the valorization of durian seeds as sustainable, value-added functional ingredients aligned with circular economy and zero-waste food processing. Full article

Refined wheat staple foods are widely criticized for low dietary fiber and high postprandial glycemic response, making soluble dietary fiber fortification a promising strategy for cereal improvement. This study investigated how resistant dextrin (RD) modulates wheat starch, gluten, dough, and bread quality through multiscale interactions. In wheat starch, 6% RD gave the best overall balance, reducing 14-day retrogradation from 57.2% to 48.6%, delaying gelatinization, and restricting amylose diffusion, with hydrogen bonding identified as a major contributing interaction. In gluten, RD increased water-holding capacity but weakened network integrity, as evidenced by reduced moduli, a shift in thiol–disulfide balance, secondary-structure redistribution (increased β-sheet, decreased α-helix/β-turn), and suppressed glutenin polymerization, yielding a looser microstructure. In dough, SEM and rheological results suggested that moderate RD (4–6%) may form a hydrated, polysaccharide-rich phase that fills structural voids and improves matrix continuity, partially offsetting gluten weakening and enhancing viscoelasticity. Overall, this study establishes a quantitative relationship between RD addition level, multiscale macromolecular interactions in wheat matrices, and the processing performance and quality of bakery products. Full article

Various tubers are cultivated in the Peruvian Andes. Olluco (Ullucus tuberosus) is consumed locally for its culinary qualities and nutritional value. In addition to its resistance to pests and extreme climatic conditions, this Andean tuber is an important source of starch. In this study, the extraction and characterization of the physical, chemical, technofunctional, and thermal properties of olluco starches from the Puka cheqche papalisa (PCP), Bela api chuqcha lisa (BACL), and Q’ello muro lisa (QML) varieties were conducted, with samples collected in 2024. Extraction yields ranged from 3.00 to 4.45%, viscosities from 6443.17 to 6892.77 cP, a high whiteness index from 90.43 to 93.52, water activity less than 0.55, and a heterogeneous particle size distribution. Amylose content ranged from 31.00 to 33.33%. FTIR analysis revealed similar functional groups and structural bonds across the varieties. For technofunctional properties, the QML variety exhibited greater water absorption, a higher solubility index, and greater swelling power. Pasting temperatures ranged from 68.70 to 71.10 °C, with low retrogradation. Thermal analysis showed good thermal stability from 104.46 to 268.42 °C, a low gelatinization temperature from 59.37 to 60.19 °C, and an enthalpy of up to 5.5757 J/g. Olluco starches have high potential for industrial applications, and their ease of cultivation makes them ideal for starch extraction. Full article

Steam conditioning is a key hydrothermal process for ensuring the quality of pelleted commercial swine compound feed. However, the molecular evolution of starch during processing remains poorly understood, particularly under the industrial constraints of limited moisture and complex substrates. This study quantified the effects of conditioning temperature (60–90 °C) and retention time (2–4 min) on starch structural reorganization across multiple length scales and in vitro digestion kinetics in pig diets. Structural evolution exhibited a nonlinear, temperature-driven pattern, with the temperature region around 80 °C representing a critical transition in structural reorganization. Although high-temperature conditioning (90 °C) increased the initial digestion rate, a nonlinear structure–digestion response was observed: final digestibility decreased, and resistant starch content rebounded. Microstructural analyses revealed that severe heat treatment was associated with the possible formation of amylose–lipid complexes (V-type crystallinity) and a more continuous protein-associated matrix, which may have imposed additional physical constraints on enzymatic hydrolysis. Consequently, maximizing starch gelatinization does not necessarily guarantee optimal in vitro digestibility. These findings integrate multiscale structural analysis with digestion kinetics, providing a mechanistic basis for balancing energy consumption, pellet quality, and nutritional value in the feed industry. Full article

This study investigated the use of aqueous pomegranate (Punica granatum L.) leaf extracts as a source of bioactive compounds in edible coatings for strawberry postharvest preservation. Extraction conditions were evaluated by varying solid-to-solvent ratio, temperature, and time, using total phenolic content (TPC) as the response variable. Response surface analysis indicated that the best predicted extraction conditions within the studied range were 1:50 (w/v), 57.36 °C, and 25 min. Among the evaluated treatments, extract C503 (1:50 (w/v), 50 °C, and 25 min) showed the highest experimental TPC (474.62 ± 21.69 mg GAE/g DM) and was selected for further characterization. This extract also showed high antioxidant capacity (FRAP: 7085 ± 72.0 µM FeSO₄/g; ABTS: 4921 ± 149.0 µM Trolox/g) and antimicrobial activity against Listeria monocytogenes and Staphylococcus aureus. When incorporated into gelatin- and starch-based edible coatings and applied to strawberries, both coatings reduced mass loss and delayed deterioration during nine days of storage at room temperature. At the end of storage, mass loss was reduced by approximately 25% with the gelatin-based coating and 11% with the starch-based coating. These results support aqueous pomegranate leaf extract as a promising source of bioactive compounds for the development of sustainable edible coatings to improve strawberry preservation. 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

Oxalis tuberosa (Oca) is traditionally cultivated in the high Andean regions of Peru and represents a promising alternative source of starch with potential industrial uses, ranking among the most essential tubers after the potato. This study aimed to evaluate the physicochemical, morphological, techno-functional, and thermal properties of starch isolated from three specific varieties of Oca (yellow, black, and white) harvested at the Ccanccayllo production center in Andahuaylas, Peru. The isolated starches exhibited high purity, characterized by high luminosity (L* > 92.28) and a whiteness index exceeding 92.10. Moisture content ranged from 9.36% to 10.01%, correlating with low water activity (a_w = 0.44), indicating stability. Notably, the amylose content was significantly higher than that of other previously studied Oca varieties. This composition contributed to a favorable water absorption capacity, solubility index, swelling power, and viscosity, with the white variety displaying superior functional performance. Colloidal stability in aqueous media was moderate, as indicated by zeta potential analysis. Particle size analysis revealed granules ranging from 26.32 to 27.74 μm, with elongated and oval morphologies confirmed by SEM, displaying characteristic functional groups. Thermal analysis (DSC) demonstrated gelatinization temperatures between 52.73 and 53.12 °C and enthalpies ranging from 4.92 to 6.11 J/g, while Thermogravimetric Analysis (TGA) indicated thermal degradation up to approximately 74–80%. These findings suggest that the studied Oca starches possess significant potential for application in the food and pharmaceutical industries due to their distinct functional properties. Full article

This research aimed to evaluate the effects of formulation and process conditions on the physical and structural properties of starch–brewers’ spent grain films. Three factors were considered: BSG amounts (0, 1, 3, 5%), a possible ultrasonication pre-treatment, and different microwave gelatinization treatments (450 W for 80 and 90 s; 900 W for 45 and 50 s). An increase in BSG is responsible for increases in moisture (10.72 → 23.40%), water absorption (67.65 → 95.73%), density (0.90 → 1.27 g/cm³), browning index (5.86 → 85.88), UV blocking capacity (82.42% → 99.96% for UV_A; 61.28% → 99.86% for UV_B), and degradability in the first 7 days (58.72 → 66.57%), but dramatically decreases the Young’s modulus and tensile strength (fallen to 2.90 N/mm² and 0.21 N/mm², at 5% BSG). Sonication contributes to increased browning index (36.17 → 37.24), UV blocking capacity, solubility (49.35 → 51.49%) and Young’s modulus (4.40 → 4.77 N/mm²). The most severe microwave treatment (900 W, 50 s) minimizes moisture (15.83%) and water absorption (80.89%) and maximizes density (1.21 g/cm³), browning index (37.52), and Young’s modulus (5.37 N/mm²). SEM micrographs allow us to observe that the film surface appears rough, and the structure becomes increasingly porous as BSG % increases. The regression analysis indicates that the quadratic model effectively describes the relationships between the three factors and each of the most important properties of the films; it is suitable for predicting film behavior and optimizing their characteristics depending on the desired use. Full article

Optimizing nitrogen (N) fertilizer application within conventional rice production systems remains essential for improving grain quality while avoiding inefficient resource use. This study examined how different N application levels influence rice quality, starch structure, and physicochemical properties in two japonica rice types cultivated under cold-region conditions in Northeast China. Using two cultivars, common japonica rice ‘Putian 1498’ and glutinous japonica rice ‘Longjing 57’, four nitrogen levels were established under machine-transplanting conditions: N0 (0 kg/hm²), N1 (80 kg/hm²), N2 (135 kg/hm²), and N3 (190 kg/hm²). The results indicate that increasing nitrogen application differentially affected the milling quality of the two rice types: it reached its maximum at the N1 level for common japonica rice and at the N3 level for glutinous japonica rice. However, the taste value decreased and chalkiness increased in both types. Regarding starch properties, increased nitrogen application led to rougher starch granule surfaces, a decrease in large granules, and an increase in medium and small granules. Starch content decreased, and the amylose-to-amylopectin ratio declined. Relative crystallinity increased, while the FTIR ratio of 1045/1022 cm⁻¹ decreased. Solubility showed an increasing trend, whereas swelling power exhibited the opposite trend. The gelatinization enthalpy and pasting temperatures were positively correlated with nitrogen rate, whereas retrogradation degree showed a negative correlation. These results demonstrate that nitrogen application regulates rice quality through changes in starch structure and physicochemical properties, with distinct responses between common and glutinous japonica rice. Moderate nitrogen input improves milling quality, but excessive application reduces eating quality, indicating a trade-off between processing performance and consumer-oriented quality. This study provides mechanistic evidence to support more precise nitrogen management in conventional rice systems, contributing to improved resource-use efficiency without overstating broader sustainability claims. In conclusion, moderate nitrogen application optimizes rice quality by balancing milling performance and eating quality through its effects on starch structure, whereas excessive nitrogen input leads to quality deterioration and inefficient resource use. Full article