Search Results (147)

Starch extracted from malanga (Colocasia esculenta) is a biopolymer with considerable industrial potential thanks to its high starch content (70–80% on a dry basis) and small granule size, which give it distinctive functional properties. To expand its applications in advanced processes such as encapsulation, it is necessary to modify its structural and physicochemical characteristics. This study evaluated the effects of ultrasound (US) and chemical cross-linking (CL) on the properties of this starch. US was applied at various times and amplitudes, while CL was performed using sodium trimetaphosphate and sodium tripolyphosphate, with sodium sulfate as a catalyst. US treatment reduced particle size and increased amylose content, resulting in lower viscosity and gelatinization temperature, without affecting granule morphology. Meanwhile, CL induced phosphate linkages between starch chains, promoting aggregation and reducing amylose content and enthalpy, but increasing the gelatinization temperature. The modified starches exhibited low syneresis, making them potentially suitable for products such as pastas, baby foods, and jams. Additionally, ultrasound modification enabled the production of fine starch microparticles, which could be applied in the microencapsulation of bioactive compounds in the food and pharmaceutical industries. These findings suggest that modified malanga starch can serve as a functional and sustainable alternative in industrial applications. Full article

Underutilized starch sources are gaining increasing recognition. However, the inherent functional deficiencies of native starch have limited its application in food industry. To counteract the deficiencies in its native characteristics, starch can be modified by acetylation. Two waxy starches (proso millet and amaranth) and four non-waxy starches (foxtail millet, quinoa, buckwheat, and oat) were modified by acetic anhydride and vinyl acetate, respectively. Degree of substitution of acetylated starches revealed that granule size did not significantly affect acetylation efficiency in starches from different plant origins. Acetylation increased peak and final viscosity of starches, with vinyl acetate exhibiting a more pronounced effect than acetic anhydride. Acetic anhydride decreased K and increased n values of non-waxy starches, showing reduced thickening ability. In contrast, vinyl acetate modification showed opposite trends, suggesting increased viscosity and pseudoplasticity. For non-waxy starches, G′_25°C, G′_0.1Hz, G′_20Hz and gel hardness decreased after acetylation, indicating that acetylation contributed to a less solid and less elastic gel network. The extent of change in vinyl acetate modification was more pronounced than that of acetic anhydride. For waxy starch, vinyl acetate modification decreased tan δ_25°C and increased gel hardness. In summary, acetylation reagent type was the major factor determining the pasting properties of acetylated starch, but the presence or absence of amylose would influence the rheological and gel properties of acetic anhydride and vinyl acetate modified starches. These findings could help unlock the potential applications of acetylated underutilized starches in the food industry. Full article

Due to its gelling and thickening properties, sweet potato starch (Ipomoea batatas L.) could be a promising ingredient to improve characteristics such as the viscosity and consistency of foods like dressings. The objective of this study was to use sweet potato starch by adding it to salad dressing-type emulsion formulations. Sweet potato starch was characterized (microscopic appearance, granule size, and thermal properties). Four formulations (F1–F4) were developed incorporating different amounts of sweet potato starch (2 and 4%), and were characterized by particle size, emulsion stability, rheology, and sensory analysis. The starch granules were oval shaped, with a size range of 10–33 μm, and a temperature and enthalpy gelatinization (ΔH) of 69.08 °C and 10.72 J/g, respectively. The formulations were evaluated for 30 days, the particle size had a range of 2.18–13.88 μm, the emulsion stability was 98.89–100%, all formulations presented a creaming index at 0%, and the coalescence rate obtained values between −2.33 × 10⁻⁸ and 7 × 10⁻⁸Kc (s⁻¹) showing a significant difference. The consistency coefficient (K) was obtained, 2.477–35.207 Pa·sⁿ, and there was no significant difference between F1 and F2 with respect to a commercial dressing. In the sensory analysis, F2 presented greater acceptance. The values obtained suggest that sweet potato starch could be used in this type of food, showing similarities to the commercial brand. Full article

The starch modification of mango cotyledons with both single ultrasound (US) and dual (US followed by octenyl succinic anhydride, OSA) was optimized by response surface methodology (RSM). The mechanochemical effects of ultrasound on amylose content, particle size, and dual modification efficiency were assessed. In addition, the structural, thermal, morphological, and functional properties were evaluated. After optimization with single US (41 min and 91% sonication intensity), sonication induced starch granule fragmentation, altering amorphous and partially crystalline regions, which increased amylose content (34%), reduced particle size (Dx50 = 12 μm), and modified granule surface morphology. The dual modification (the subsequent OSA reaction lasted 4.6 h under the same conditions) reached a degree of substitution of 0.02 and 81% efficiency, imparting amphiphilic properties to the starch. OSA groups were mainly incorporated into amorphous and surface regions, which decreased crystallinity, gelatinization temperature, and enthalpy. The synergistic effect of the modification with US and OSA in the dual modification significantly improved the solubility and swelling power of starch, resulting in better dispersion, functionality in aqueous systems, and chemical reactivity. These findings highlight the potential of dual modification to transform mango cotyledon starch into a versatile ingredient in the food industry as a thickener, a stabilizer in soups and sauces, an emulsifier, a carrier of bioactive and edible films; in the cosmetic industry as a gelling and absorbent agent; and in the pharmaceutical industry for the controlled release of drugs. Furthermore, valorizing mango cotyledons supports circular economy principles, promoting sustainable and value-added food product development. Full article

The modification effects of industry-scale microfluidizer (ISM) technology on small-sized rice starch remain unknown. This study systematically evaluated the effects of ISM treatment on the structural characteristics (granular morphology, crystallinity, and short-range order) and physicochemical properties (thermal, pasting, and rheological properties) of rice starch. Scanning electron microscopy (SEM) analysis revealed that ISM treatment induced the aggregation of starch granules, leading to an increase in particle size. Furthermore, ISM treatment resulted in starch damage, as evidenced by an increase in the damaged starch content from 4.25% to 17.99%. X-ray diffraction (XRD) analysis found that the relative crystallinity decreased from 29.01% to 20.74%, and Fourier-transform infrared (FTIR) spectroscopy implied that the absorbance ratio of 1047 cm⁻¹/1022 cm⁻¹ decreased from 0.88 to 0.73, indicating the disorganization of long-range crystalline structure and short-range ordered structure. Differential scanning calorimetry analysis demonstrated that ISM treatment reduced the gelatinization enthalpy of rice starch, with a gelatinization degree reaching 31.39%. Rapid visco analyzer (RVA) measurements indicated that ISM treatment increased the pasting viscosity of rice starch. However, the effect of ISM treatment on the dynamic rheological properties was minimal, with a slight enhancement in the loss modulus, while in-shear structural recovery rheology showed no significant impact on the ability of starch gels to recover their original structure. These results suggested that ISM technology effectively modified rice starch, leading to a disrupted structure, increased viscosity, and preserved gel network structure. This approach offers a novel strategy for the application of industry-scale microfluidizers in the development of rice-based products. Full article

As an important characteristic and horticultural crop in China, sweetpotato can be used as food, industrial raw material, vegetable, and ornamental material. Purple sweetpotato for table use is rich in anthocyanin, which leads to some bitter taste, so it needs further quality improvement. Genetic engineering technology is an effective method to improve crop traits, but there are few reports on genes that can improve sweetpotato sweetness and taste. A xylosidase gene (Ibα-XYL1) was cloned from sweetpotato variety ‘Yanshu 25’ with a fragment size of 2796 bp and encoding 932 amino acid sequences. It has a typical transmembrane domain and three functional domains, which are localized at cell membrane. Reduction in Ibα-XYL1 gene expression had no significant effect on the expansion characteristics and anthocyanin content of sweetpotato storage root (SPSR), but it could up-regulate the expression of sucrose synthesis related genes (SuS, SuPS) and promote the accumulation of soluble sugar in fresh transgenic SPSR. At the same time, it could up-regulate the expression of genes related to starch synthesis modifications (GASS, SBE) and starch decomposition (AMY and BAM), reduce the starch granule size and the starch pasting temperature, promote the conversion of starch to maltose, increase the soluble sugar content, and improve the sweetness and taste of steamed transgenic SPSR. The results are of great significance for quality improvement of sweetpotato. Full article

Rice (Oryza sativa L.) is essential for global food security and sustains billions worldwide, emphasizing the need to improve production and quality. One key challenge in rice breeding is the inheritance and environmental sensitivity of amylose content, a starch component that influences the texture, water absorption, and firmness after cooking, which are crucial for market acceptance. While international markets prefer low-amylose varieties for their softness, intermediate- and high-amylose varieties are favored in Latin America for their firmness. The objective of this study was to develop a molecular quality assessment methodology that, combined with morphological and culinary evaluations, helps in the selection of rice varieties during the breeding process. First, ten Ecuadorian rice materials were evaluated for milling and culinary quality characteristics, revealing significant grain size, sterility, milling yield, cooking time, and texture variations. Amylose content (AC) is genetically regulated by the waxy gene and its allelic variants, affecting granule-bound starch synthase (GBSS) enzyme expression. Secondly, to classify rice varieties molecularly based on AC, the testing ten genotypes plus nine control varieties were analyzed using microsatellite (SSR) markers. The waxy molecular marker, combined with metaphor agarose gel electrophoresis (MAGE), proved effective for early-stage AC analysis, reducing variety selection costs and improving breeding efficiency. Additionally, a restriction enzyme protocol assay facilitated variety differentiation by selectively cleaving the waxy gene sequence at a specific single-nucleotide polymorphism (SNP) site, allowing for precise AC genetic classification. By integrating molecular techniques with traditional assessments, this study reveals that using marker-assisted selection in breeding programs, as well as supporting the identification and development of high-quality local rice varieties to meet market demands, improves production efficiency and optimizes the assessment of developing varieties under diverse environmental conditions. Full article

Polygonum multiflorum Thunb. (PM) is a starch-rich medicinal herb, but research on the changes in the structure and physical properties of the starch upon processing remains elusive. Herein, the structures and physicochemical properties, particularly the impact on intestinal flora of raw PM starch and processed Polygonum multiflorum (PMP) starch, were systematically characterized and compared. XRD and FT-IR results showed that the crystalline structure of PMP starch was disrupted, with the increase in its short-range ordering. Morphological analysis revealed that the size of PMP starch granules increased with the appearance of aggregation. Significant differences in swelling power and solubility were observed, wherein PM starch has a higher swelling power, while its solubility is lower than that of PMP starch. The PM starch also has higher thermal stability. Interestingly, the resistant starch (RS) content in PMP starch was higher, as shown by the in vitro digestibility tests, which is associated with enhanced bioactivity. Moreover, gut microbiota analysis in mice indicated that PMP starch promoted gut health by regulating specific bacterial families. Our current study has offered full insights into the changes of PM starch upon processing, laying a solid foundation for further developing PM starch-derived functional food products. Full article

The spray-dried potato starch was produced by gelatinizing native potato starch at two concentrations of 3% and 5% at 75 °C for 30 min, followed by drying in a pilot-scale spray dryer. X-ray diffraction (XRD), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and optical microscopy were applied to characterize native potato starch and spray-dried (SD) potato starch powders. The physical properties of the starches, including moisture content, color, bulk density, tapped density, particle size parameters, water holding capacity, and hygroscopicity, were investigated. XRD, DSC, and FTIR revealed the formation of a semi-crystalline to amorphous structure in the spray-dried starch powders. Microscopic examination showed that the starch granules of native potato starch were spherical and regular in shape, while spray-dried (SD) starch powders displayed wrinkled granules. The moisture content of the spray-dried powders was significantly lower than that of the native starch, while the native starch had higher particle size values [D(4.3)] compared to the spray-dried powders. Higher water holding capacity values were also recorded in the spray-dried starches compared to the native starch. Regarding the color parameters, statistical analysis revealed similar values for lightness (L*) and yellowness (YI) indices, while significant differences were found in hue angle (H°), a*, and b* values. A principal component analysis (PCA) was carried out to investigate the relationships among the physical properties of the native potato starch and spray-dried starch powders. The findings of the present study highlight the potential application of physically modifying starch through the spray-drying process. Full article

Sweet potato (Ipomoea batatas (L.) Lam.; SP) flour enhances food nutrition and bioactivity while functioning as a thickening/gelling agent. This study investigated the impact of two drying methods [hot-air (75 °C/20 h) and freeze-drying (−41–30 °C/70 h)] on the physical–functional properties of flours from three SP varieties: Bonita (white-fleshed), Bellevue (orange-fleshed), and NP1648 (purple-fleshed). Particle size, morphology, water/oil absorption capacities (WAC/OAC), bulk density, swelling power (SwP), water solubility (WS), foaming/emulsifying properties, least gelation concentration (LGC), and gelatinisation temperature (GT) were analysed. Both the drying method and variety significantly influenced these properties. Hot-air-dried flours exhibited bimodal particle distribution, compact microstructure, and aggregated starch granules, yielding higher WAC (≈3.2 g/g) and SwP (≈3.6 g/g). Freeze-dried flours displayed smaller particles, porous microstructure, and fragmented granules, enhancing OAC (≈3.0 g/g) and foaming capacity (≈17.6%). GT was mainly variety-dependent, increasing as Bellevue (74.3 °C) < NP1648 (78.5 °C) < Bonita (82.8 °C), all exceeding commercial potato starch (68.7 °C). NP1648 required lower LGC (10% vs. 16% for others). All flours exhibited high WS (24–39.5%) and emulsifying capacity (≈44%). These results underscore the importance of selecting the appropriate drying method and variety to optimise SP flour functionality for targeted food applications. Freeze-dried flours might suit aerated/oil-retentive products, while hot-air-dried flours could be ideal for moisture-sensitive formulations. Full article

Plantain (Musa AAB Simmonds) of the Dominico hartón variety from two Colombian territories (Cauca and Risaralda) with differences in altitude was used to extract the flour and starch from the pulp and peel. The plantain of Cauca origin presented the highest yield in flour extraction. Starch extraction was based on the use of an aqueous solution of sodium metabisulfite, achieving the highest yield in starch extraction (above 80% d.b.) when using a concentration of 1.2% of sodium metabisulfite, highlighting the best performance in the plantain of Risaralda origin. In the characterization of the starches, the granules from the pulp showed a larger size, higher amylose content, lower ash content, lower water absorption and solubility capacity, higher melting enthalpy, and higher crystallinity than those obtained with the starches from the banana peel. The starch from Cauca pulp presented properties characteristic of a structure with higher hardness. Full article

Applying physical modification methods to raise the resistant starch content is a feasible strategy for developing foods with a low glycemic index (GI) and regulating postprandial hyperglycemia. Here, broken rice starch (C) was modified via ultrasound and quercetin complexation (US-Q). The structure, physicochemical properties, and in vitro digestibility of the US-Q product were subsequently determined. Scanning electron microscopy (SEM) images showed that the modification changed the starch granules’ morphology, forming a more compact and stable structure. Fourier transform infrared (FTIR) spectroscopy images revealed the interaction between the starch and quercetin. An X-ray diffraction (XRD) analysis demonstrated that the crystallinity of the US-Q was lower than that of the C, indicating that the combined modification with ultrasound and quercetin disrupted the long-range ordered structure of the starch and facilitated the formation of a short-range ordered structure from amylose. Size exclusion chromatography (SEC) images showed that both the molecular weight (from 72,080.96 kDa to 85,141.95 kDa) and amylose content (from 15.94% to 26.76%) increased significantly, while the branching degree and average degree of polymerization of amylopectin decreased, suggesting that the ultrasonic treatment processing method had a significant impact on the formation of the quercetin–starch complexes. In terms of in vitro digestion, the resistant starch content of the US-Q was significantly increased from 6.57% to 20.23%, whereas the hydrolysis rate was decreased from 92.6% to 78.35%, indicating that the presence of quercetin reduced the digestibility of the starch complexes by inhibiting the starch-hydrolyzing enzyme activity. Overall, this study improves the understanding of ultrasound and quercetin dual treatment of broken rice starch, providing a theoretical basis for the development of low-GI starch foods for industrial applications. Full article

The morphology of wheat starch granules with different damaged starch (DS) content was analyzed using a particle size analyzer and scanning electron microscopy (SEM); the granular structure was studied using FT-IR spectroscopy and X-ray diffraction (XRD); and the granule–water interaction was evaluated by thermogravimetric analysis (TGA) and dynamic vapor sorption (DVS). The increase in the level of DS shifted the population of B-type granules towards larger particle diameters and shifted the population of A-type granules towards smaller particle diameters. The appearance of the surface of the starch-damaged granules was rough and flaky (SEM images). Crystallinity reductions were related to higher mechanical damage levels of the granular structure (FT-IR and XRD). Higher DS increased the liquid-water absorption capacity of the granules. Higher DS was associated with increments in less-bound water proportions and reductions in more strongly bound water proportions and related to reductions in the evaporation temperature of these water populations (TGA analyses). Concerning DVS data, the results suggested that the driving force for water–monolayer attachment to the starch granules decreased as DS increased. Therefore, it was suggested that the changes in granule structure led to a weaker water–starch polymer chain interactions due to the increase in DS. The results contribute to a better understanding of the influence of mechanical damage on the starch granular structure, which could be related to the rheological and thermal behavior of starch-based systems with different DS. Full article

This study investigates the effects of fermentation modification and combined modification with heat-moisture treatment (HMT) on the multiscale structure, physical and chemical properties, and quality of corn flour in the production of traditional fermented corn noodles (TFCNs). The results indicate that after fermentation modification, the starch granule size decreased while the amylopectin proportion increased. Fermentation also enhanced the relative crystallinity and short-range order of the starch, along with an increase in resistant digestion components and ester content in the noodles. After combined modification with HMT, starch granules lost their spherical, intact structure, underwent melting and reorganization, and displayed an increase in particle size. These changes led to a significant improvement in the thermal stability and textural properties of corn flour, resulting in noodles with enhanced cooking quality. Furthermore, the combined modification significantly increased the contents of flavor compounds such as aldehydes, acids, and alcohols in the noodles while reducing olefin and alkane levels, thus contributing to improved flavor development. These findings demonstrate that fermentation modification and combined modification with HMT play a crucial role in enhancing the multiscale structure and physical and chemical properties of corn starch, thereby improving the quality of TFCN. Full article

This study investigated the impact of whey protein isolate (WPI) addition on the dry heat modification of corn (CS) and wheat starch (WS). Starches were treated under dry heating conditions at 130 °C for 2 and 4 h. The physicochemical and structural properties of the modified starches, such as color, particle size, thermal behavior (DSC), crystalline structure (XRD), and surface morphology (SEM), were analyzed. The results show that adding WPI significantly altered the gelatinization properties, surface morphology, and crystalline structure of both starches. DSC indicated that the gelatinization properties of starch/WPI mixtures varied, with corn starch showing a decreased gelatinization temperature and increased enthalpy, whereas wheat starch exhibited a more complex response, likely due to different structural changes. The XRD and FTIR results revealed WPI-enhanced crystallinity and structural changes, highlighting WPI-induced aggregation. Wheat starch, in particular, exhibited stronger interactions with WPI than corn starch, as evidenced by the accumulation patterns in the SEM images. The oil-binding capacity of native starches increased with dry heating and WPI addition, suggesting an improved hydrophobicity of starch granules. Dry heating and WPI addition significantly altered starch properties, highlighting the potential of thermal modulation to enhance starch–protein systems for targeted food applications. Full article