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1.
Food Res Int ; 184: 114254, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38609232

RESUMO

Polysaccharides have a significant impact on the physicochemical properties of starch, and the objective of this study was to examine the effect of incorporating soluble soybean polysaccharide (SSPS) on the gelatinization and retrogradation of corn starches (CS) with varying amylose content. In contrast to high-amylose corn starch (HACS), the degree of gelatinization of waxy corn starch (WCS) and normal corn starch (NCS) decreased with the addition of SSPS. The inclusion of SSPS resulted in reduced swelling power in all CS, and led to a decrease in gel hardness of the starches. The intermolecular forces between SSPS and CS were primarily hydrogen bonding, and a gel network structure was formed, thereby retarding the short-term and long-term retrogradation of CS. Scanning electron microscopy results revealed that the addition of SSPS in starches led to a loose network structure with larger poles and a reduced ordered structure after retrogradation, as observed from the cross-section of formed gels. These findings suggested that SSPS has great potential for applications in starchy foods, as it can effectively retard both gelatinization and retrogradation of starches.


Assuntos
Amilose , Soja , Zea mays , Amido , Polissacarídeos , Amilopectina
2.
Food Chem ; 446: 138803, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38412810

RESUMO

The objective of this study was to enhance the bioavailability and stability of curcumin (Cur) by encapsulating it in corn starch (CS)/octenylsuccinic acid modified (OSA)-starch-whey protein isolate (WPI) emulsion gels (EGs). As the volume fraction of the oil phase increased, the droplet size and ζ- potential of the EGs decreased. The encapsulation efficiency and bioavailability of Cur in CS/OSA-starch-WPI EGs with a 60% oil ratio were 96.0% and 67.3%, respectively. The release rate of free fatty acid and the bioavailability of Cur from the EGs after digestion were significantly higher compared to Cur dissolved in oil. EGs with an oil phase volume fraction of 75% and 80% demonstrated greater protection against light irradiation but were less effective against UV irradiation compared to EGs with a 60% oil phase volume fraction. Encapsulation in EGs proved to be an effective method for enhancing the bioavailability and stability of Cur.


Assuntos
Curcumina , Amido , Succinatos , Emulsões , Proteínas do Soro do Leite , Zea mays , Géis
3.
Artigo em Inglês | MEDLINE | ID: mdl-38418805

RESUMO

This study investigated whether the interference between two tasks in dual-task processing stems from bottleneck limitations or insufficient cognitive resources due to resource sharing. Experiment 1 used tone discrimination as Task 1 and word or pseudoword classification as Task 2 to evaluate the effect of automatic versus controlled processing on dual-task interference under different SOA conditions. Experiment 2 reversed the task order. The results showed that dual-task interference persisted regardless of task type or order. Neither experiment found evidence that automatic tasks could eliminate interference. This suggests that resource limitations, rather than bottlenecks, may better explain dual-task costs. Specifically, when tasks compete for limited resources, the processing efficiency of both tasks is significantly reduced. Future research should explore how cognitive resources are dynamically allocated between tasks to better account for dual-task interference effects.

4.
Int J Biol Macromol ; 261(Pt 2): 129920, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38311128

RESUMO

A novel chestnut porous starch nanoparticle (PSNP) was successfully synthesized, combining the properties of starch nanoparticle (SNP) and porous starch. The SNP obtained through ultrasonic and acid hydrolysis, exhibited a smaller particle size (173.9 nm) and a higher specific surface area (SSA) compared to native starch. After the synergistic hydrolysis by α-amylase and glucoamylase, the porous structure appeared on the surface of SNP. The prepared PSNP had a size of 286.3 nm and the highest SSA. In the adsorption experiments, PSNP showed higher capacities for adsorbing water, oil and methylene blue (MB) compared to other samples. The acid and enzymatic treatments resulted in a decrease in the levels of total starch content and amylose ratio. Furthermore, the treatments increased the levels of relative crystallinity (RC) and solubility, while decreasing the short-range ordered structure and swelling ratio at high temperatures. It was observed that the SSA of starch granules positively correlated with the MB and water adsorption capacity (WAC), solubility, and RC. These findings highlight the potential of the novel PSNP as an efficient adsorbent for bioactive substances and dyes.


Assuntos
Nanopartículas , Amido , Amido/química , Porosidade , Amilose/química , Hidrólise , Água/química
5.
Cognition ; 246: 105744, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38364443

RESUMO

Counterfactual reasoning helps people to learn from the past to prepare for the future. In contrast to English with counterfactual markers that directly signal counterfactual reasoning, Mandarin Chinese indicates counterfactual reasoning by counterfactuality enhancers, which enhance rather than directly signal entry into the counterfactual realm. There are more counterfactuality enhancers in subtractive than additive counterfactual premises. Hence, Chinese-speaking children might more readily interpret subtractive than additive counterfactual premises, leading to better performance on subtractive than additive counterfactual reasoning tasks. This difference between logical structures might be larger in Chinese than English, as English has counterfactual markers, which enable direct inference of counterfactuality regardless of logical structures. Consistent with these propositions, in two experiments, the present study found that Chinese preschool children's accuracy was significantly higher for subtractive than additive counterfactual reasoning. Also, the difference between logical structures was much larger compared to a previous study in UK children using a similar counterfactual reasoning task. Hence, the use of counterfactuality enhancers in Chinese might shape a developmental difference between subtractive and additive counterfactual reasoning. Parents and teachers may attend to this developmental pattern when scaffolding children's counterfactual reasoning growth.


Assuntos
Lógica , Resolução de Problemas , Humanos , Pré-Escolar , Povo Asiático , China
6.
Plant Foods Hum Nutr ; 79(1): 189-193, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38315314

RESUMO

Due to the limitations of the properties of chestnut flour, its applications have been restricted. The objective of this study is to investigate the impact of whey protein isolate (WPI) and xanthan gum (XG) on the functional and digestive properties of chestnut flour, specifically focusing on gel texture, solubility and swelling power, water absorption capacity, freeze-thaw stability and starch digestibility. The addition of both WPI and XG reduced the gel hardness, gumminess and chewiness of the co-gelatinized and physically mixed samples. Furthermore, the inclusion of physically mixed WPI and XG led to an increase in the solubility (from 58.2 to 75.0%) and water absorption capacity (from 3.11 to 5.45 g/g) of chestnut flour. The swelling power of the chestnut flour was inhibited by both additives. WPI was superior to XG at maintaining freeze-thaw stability, by reducing the syneresis from 71.9 to 68.1%. Additionally, WPI and XG contributed to the inhibition of starch hydrolysis in the early stage of digestion, resulting in a lower starch digestibility of chestnut flours. This research provides insights into the interaction mechanisms between WPI, XG, and chestnut flour, offering valuable information for the development of chestnut flour products with enhanced properties.


Assuntos
Farinha , Polissacarídeos Bacterianos , Amido , Proteínas do Soro do Leite , Água
7.
Int J Biol Macromol ; 254(Pt 1): 127704, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37898245

RESUMO

Chestnuts are a starchy food with a characteristic glutinous taste that is often used to assess their quality. In this study, our findings indicated that chestnuts with higher glutinous taste quality had lower amylose content and microcrystalline structures, as well as higher subcrystalline structures and relative crystallinity in both the raw and steamed starches. In the leached starch, chestnuts with higher glutinous taste quality had lower amylopectin B1 chains and microcrystalline structure, but higher amylopectin B2 chains, subcrystalline structure and relative crystallinity. These results suggest that amylose content, relative crystallinity, and amylopectin chain length distribution are important factors determining the glutinous taste quality of chestnuts. To further enhance our understanding of these factors, an sensory evaluation model was developed based on textural profile analysis parameters. This study provides valuable insights into the relationship between molecular structure of starch and the glutinous taste quality of starchy foods.


Assuntos
Oryza , Amido , Amido/química , Amilopectina/química , Amilose/química , Estrutura Molecular , Paladar , Oryza/química
8.
Food Chem ; 440: 138203, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38104452

RESUMO

Whole grains have garnered significant attention in the food industry due to their retained abundant nutrients when compared to refined grains. However, limited knowledge exists regarding the digestive behavior of starch and protein. This study compared the physicochemical properties and in vitro starch and protein digestibility of cooked whole wheat flour (WF) and naked oat flour (NOF), and evaluated the impact of endogenous components (protein, lipid, ß-glucan, and polyphenol) on the physicochemical properties and digestibility of WF and NOF. The result indicated that the final hydrolysis rate of WF samples (starch: 23.2 %∼46.3 %; protein: 23.1 %∼63.0 %) was lower than that of NOF samples (starch: 32.1 %∼61.0 %; protein: 32.3 %∼63.6 %). The removal of different endogenous components led to improved digestibility of starch and protein in both WF and NOF. This study contributes to the understanding of the starch and protein digestibility of whole grains, consequently facilitating the development of whole grain products.


Assuntos
Farinha , Amido , Amido/química , Triticum/metabolismo , Avena/química , Proteínas
9.
Percept Mot Skills ; 130(6): 2430-2449, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37905513

RESUMO

Previous studies of illusory conjunction (IC) mainly focused on alphabetic languages, while researchers have poorly understood the IC mechanism of Chinese words as an ideographic writing system. In the present study, we aimed to investigate the dynamic changes of IC effects for Chinese words under different stimulus exposure times and spatial arrangements. We conducted two experiments with a 3 (Condition: IC, non-IC-same, non-IC-different) × 3 (Exposure time: 38 ms, 88 ms, 138 ms) within-subject design. The results showed that in the IC condition, the two characters recombined regardless of exposure time as long as they could form an orthographically correct new word, demonstrating the universality of IC. In non-IC conditions, increasing exposure time decreased response time and significantly reduced error rate, indicating that attention played a decisive role in perceptual processing. The spatial arrangement had no impact on IC production. These findings support the feature confirmation account model, suggesting that attention modulates IC through top-down feature confirmation processes. These data expand an understanding of IC mechanisms, validate the role of attention in feature confirmation, and elucidate the inimitable mechanism of the Chinese word IC influenced by both low-level visual processing and high-level cognitive control.


Assuntos
Ilusões , Humanos , Percepção Visual/fisiologia , Idioma , Atenção/fisiologia , Tempo de Reação , Reconhecimento Visual de Modelos
10.
Opt Express ; 31(17): 28624-28635, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37710912

RESUMO

In this study, using density functional theory, we calculated the band structure and photoelectric properties in a series of 12.5% B-doped (B = Ge, Sn, Ca, and Sr) CsPbI3 perovskite systems. It is found that Ge doping can improve the structural stability and is more conducive to applications under high-pressure or by applying stress via calculating the bond length, formation energy, elastic properties, and electronic local function. In addition, the optimal direction for applying stress is achieved according to the elastic properties. Furthermore, in terms of electronic properties, the reason of energy band variation and the influence of chemical bond on the structural stability of doped α-CsPbI3 are investigated. The possibility of the applications of the CsPb0.875B0.125I3 perovskite is explored based on the optical properties. Thus, the theoretical study of the CsPb0.875B0.125I3 perovskite provides novel insights into the design of next-generation photoelectric and photovoltaic materials.

11.
Sci Rep ; 13(1): 8383, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37225728

RESUMO

Neuroplasticity research supports the idea that varied practice and new environments promote cognitive engagement and enhance learning. Expanding on a meta-analysis of the effect of physical activity interventions on cognition and academic outcomes, we reviewed and quantified the impact of task and environmental factors that foster creative physical activity. Interventions were considered as fostering creative physical activity to a greater extent if (1) they were varied, (2) relied less on technical acquisition, instruction or demonstration, (3) involved open spaces, props, or open-ended instructions, and (4) involved interactions with peers. A wide range of physical activities were considered, from dance to aerobic exercise across 92 studies in 5-12-year-old children. Creativity ratings of physical activity interventions were varied but did not associate with greater beneficial effects on executive functions (k = 45), academic achievement (k = 47), or fluid intelligence (k = 8). Studies assessing on-task behaviour (k = 5) tended not to foster creativity, while reversely studies assessing creativity tended to foster creative physical activities (k = 5). As a group, three studies that fostered more creative PA showed a small significant negative summary effect on cognitive flexibility. Considering qualitative differences in the physical activities performed in schools will improve our understanding of their mechanisms of impact. Future research should consider using more varied measures, including more proximal outcomes that involve body movements (e.g., a Simon Says task to measure inhibitory control).


Assuntos
Sucesso Acadêmico , Cognição , Criança , Humanos , Pré-Escolar , Instituições Acadêmicas , Escolaridade , Exercício Físico
12.
Phys Chem Chem Phys ; 25(13): 9592-9598, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36942656

RESUMO

To broaden the application of cesium lead halide perovskites, doping technology has been widely proposed. In this study, we calculated a 12.5% concentration of a Sr-doped CsPbX3 (X = Cl, Br, or I) perovskite via density functional theory. The results showed that the bandgap energy of the perovskite increased by 0.2-0.3 eV. The high symmetry points of the energy band changed from R to Γ after Sr doping because the Sr doping affected the initial distribution of atomic orbital hybridization. In addition, optical absorption spectra after doping showed an obvious blueshift, whereas the absorption coefficient of CsPb0.875Sr0.125X3 had the same magnitude as undoped CsPbX3. Moreover, the effective masses of electrons and holes changed within a small range (0.01-0.03 m0) after Sr doping. According to the findings of this study, the CsPb0.875Sr0.125X3 perovskite is expected to become an ideal candidate material for designing photovoltaic and photoelectric devices.

13.
Food Chem ; 406: 135040, 2023 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-36462356

RESUMO

This study aimed to prepare a starch-based aerogel with microporous network structure, and to investigate its physicochemical properties after ß-carotene encapsulation. Corn starch aerogels (CSA) prepared with sodium hexametaphosphate (SHMP) as a cross-linking agent and ß-carotene encapsulation were evaluated in terms of morphology, long- and short-range molecular order, bioavailability, and stability. After encapsulating ß-carotene, the morphology of SHMP-CSA showed that the aerogels presented agglomeration, and the relative crystallinity increased from 17.2% to 22.2%. The characteristic bands of ß-carotene were not found in the FT-IR pattern, and the short-range molecular order of aerogel was decreased, proving that ß-carotene was well embedded in the aerogel. During the simulated in vitro release process, ß-carotene was almost completely released. After ultraviolet or light irradiation, the retention rate of ß-carotene was much higher than that in the control group. These results demonstrated that SHMP-CSA encapsulation could effectively improve the stability of ß-carotene.


Assuntos
Amido , beta Caroteno , Amido/química , beta Caroteno/química , Zea mays , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Food Chem ; 406: 135009, 2023 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-36450195

RESUMO

Starchy foods are a major energy source of the human diet, their digestion is closely related to human health. Most foods require lots of processing before eating, therefore, many factors can influence starch digestibility. The factors that affect the digestibility of starches have been widely discussed previously, but the extracted starches in those studies were different from those present within the actual food matrix. This review summarizes the factors influencing the starch digestibility in starchy foods. Endogenous non-starch components hinder the starch digestive process. Food ingredients and additives decrease starch digestibility by inhibiting the activity of digestive enzymes or hindering the contact between starch and enzymes. Storage induce the retrogradation of starch, decreasing the digestibility of foods. Therefore, preparing starchy foods with whole grains, processing them as little as possible, using food additives reasonably, and storage conditions may all be beneficial measures for the production of low GI foods.


Assuntos
Digestão , Amido , Humanos , Alimentos , Dieta , Aditivos Alimentares
15.
Plant Foods Hum Nutr ; 78(1): 166-172, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36469235

RESUMO

Microwave treatment, roasting, boiling, and enzymatic treatment were used to prepare cooked and instant chestnut flour, and the in vitro digestibility were compared. Cooking gelatinized the starch and destroyed the granular and crystal structure, increasing starch digestibility. After enzymatic hydrolysis, starches were degraded by 20~24%, and the reducing sugar content of the instant flours increased by 79~94%. Starch digestibility was reduced after enzymatic hydrolysis, however, the estimated glycemic index (GI) increased to 65.1 ~ 77.7 due to the combined effect of increased reducing sugar and decreased starch hydrolysis in the instant flours. The chestnuts treated by 'boiling + enzymes' are still a medium GI food. These findings give guidance for the development of low GI cooked and instant chestnut flour.


Assuntos
Culinária , Farinha , Farinha/análise , Amido/química , Hidrólise , Açúcares , Digestão
16.
Atten Percept Psychophys ; 84(8): 2596-2606, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36207662

RESUMO

Previous studies have found that the spatial-numerical association of the response codes (SNARC) effect automatically occurred when processing both numbers and non-symbolic magnitudes. However, this conclusion was challenged by several recent studies that found no SNARC effect when processing non-symbolic magnitudes with a directional cue. In the present study, we hypothesized that automatic spatial association of non-symbolic magnitudes would be inhibited by directional cues; thus, we utilized left and right arrow stimuli with different luminance levels to systematically investigate the spatial association of luminance. To ensure that participants could effectively discriminate the luminance stimuli, we first replicated the SNARC effect in Experiment 1, by presenting rectangles with different luminance levels. Then, arrows with the same luminance levels as the rectangles were randomly presented to participants on the centre of a screen; participants completed direction classification (Experiment 2), colour classification (Experiment 3), or luminance classification (Experiment 4) tasks with these arrow stimuli. We found that (1) the SNARC effect was present when processing rectangles with different luminance levels (Experiment 1); however, (2) the Simon-like effect rather than the spatial association of luminance was observed when processing arrows with different luminance levels in the luminance-irrelevant classification tasks (Experiments 2 and 3) and the luminance-relevant classification task (Experiment 4). These results indicate that processing of a directional cue inhibited the spatial association of luminance in both luminance-relevant and luminance-irrelevant classification tasks.


Assuntos
Sinais (Psicologia) , Percepção Espacial , Humanos , Percepção Espacial/fisiologia , Tempo de Reação/fisiologia
17.
Nanomaterials (Basel) ; 12(17)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36080019

RESUMO

Lead-free perovskites of Cs3Sb2X9 (X = Cl, Br, or I) have attracted wide attention owing to their low toxicity. High pressure is an effective and reversible method to tune bandgap without changing the chemical composition. Here, the structural and photoelectric properties of Cs3Sb2X9 under high pressure were theoretically studied by using the density functional theory. The results showed that the ideal bandgap for Cs3Sb2X9 can be achieved by applying high pressure. Moreover, it was found that the change of the bandgap is caused by the shrinkage of the Sb-X long bond in the [Sb2X9]3- polyhedra. Partial density of states indicated that Sb-5s and X-p orbitals contribute to the top of the valence band, while Sb-5p and X-p orbitals dominate the bottom of the conduction band. Moreover, the band structure and density of states showed significant metallicity at 38.75, 24.05 GPa for Cs3Sb2Br9 and Cs3Sb2I9, respectively. Moreover, the absorption spectra showed the absorption edge redshifted, and the absorption coefficient of the Cs3Sb2X9 increased under high pressure. According to our calculated results, the narrow bandgap and enhanced absorption ability under high pressure provide a new idea for the design of the photovoltaic and photoelectric devices.

18.
Foods ; 11(6)2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35327248

RESUMO

The present study investigated the multi-scale structure of starch derived from acorn kernels and the effects of the non-starch nutrients on the physicochemical properties and in vitro digestibility of starch. The average polymerization degree of acorn starch was 27.3, and the apparent amylose content was 31.4%. The crystal structure remained as C-type but the relative crystallinity of acorn flour decreased from 26.55% to 25.13%, 25.86% and 26.29% after the treatments of degreasing, deproteinization, and the removal of ß-glucan, respectively. After the above treatments, the conclusion temperature of acorn flour decreased and had a significant positive correlation with the decrease in the crystallinity. The aggregation between starch granules, and the interactions between starch granules and both proteins and lipids, reduced significantly after degreasing and deproteinization treatments. The endogenous protein, fat, and ß-glucan played key roles in reducing the digestibility of acorn starch relative to other compounds, which was dictated by the ability for these compounds to form complexes with starch and inhibit hydrolysis.

19.
Phys Chem Chem Phys ; 24(9): 5448-5454, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35171170

RESUMO

Based on density functional theory and following first-principles methods, this paper investigated the electronic structures, densities of states, effective masses of electrons and holes, and optical properties of CsGeX3 (X = I, Br or Cl) perovskites under triaxial strains of -4% to 4%. The calculated results show that the tuning range of the bandgaps of the CsGeI3, CsGeBr3, and CsGeCl3 perovskites are 1.16 eV, 1.64 eV, and 1.63 eV, respectively. This result shows that the bandgap of the CsGeX3 perovskite is tuned over the entire visible spectrum by applying strain. Also, it is found that the change of the bandgap is caused by the change of the Ge-X long bond. Besides, the optimal bandgaps of CsGeI3 and CsGeBr3 can be achieved by applying compressive strains, providing theoretical support for adjusting the bandgaps of CsGeX3 perovskites. The effective masses of electrons and holes of CsGeX3 perovskites decrease gradually with the strains changing from 4% to -4%, which is conducive to the transmission of electrons and holes. In addition, the optical properties of CsGeX3 perovskites change from redshifted to blueshifted under different strains.

20.
Food Chem ; 377: 131990, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-34999449

RESUMO

The effects of ultrasound and microwave on the physicochemical properties of normal maize and potato starches were compared. The cavitation effect of ultrasound loosened the internal space and destroyed the structure of starch granules, increased the damaged starch content, which was consistent with the decrease in relative crystallinity and the number and brightness of Maltese crosses, and the increase in D(0.5) and D(4,3) values. Microwave vibrated the molecules inside the granules and generated heat to destroy the structure of starch. The content of damaged starch was significantly lower in microwave-treated starch compared with ultrasound-treated starch. Microwave treatment promoted the formation of amylose-lipid complex, with the larger peak area at 20°(2θ) than that of the ultrasound-treated starch. The type of starch and the treatment sequence showed a significant effect. The results might help understand the mechanism of ultrasound and microwave treatments influencing the structural properties of starches.


Assuntos
Solanum tuberosum , Zea mays , Amilose , Micro-Ondas , Amido
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