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1.
Foods ; 13(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38890834

RESUMO

Climate warming is a critical environmental issue affecting rice production. However, its effects on cooked rice texture and rice thermal properties remain unstudied in China. To address this gap, we conducted a two-year multi-site field warming experiment using free-air temperature increase facilities across three major Chinese rice cropping systems. Interestingly, warming had a minimal impact on the hardness of cooked rice, while it significantly increased stickiness by an average of 16.3% under warming conditions. Moreover, compared to control treatments, rice flour exhibited a significant increase in gelatinization enthalpy, onset, peak, and conclusion temperatures under warming conditions, with average increments of 8.7%, 1.00 °C, 1.05 °C, and 1.17 °C, respectively. In addition, warming significantly declined the amylose content, remarkedly elevated the protein content and relative crystallinity, and altered the weight distribution of the debranched starch. Correlation analysis revealed significant relationships between cooked rice stickiness, rice flour thermal properties, amylose content, protein content, and partial starch structures. Therefore, warming-induced alterations in rice composition and starch structure collectively enhanced cooked rice stickiness and rice thermal stability.

2.
Food Chem X ; 20: 100965, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38144815

RESUMO

Straw return can improve rice eating quality by modifying starch formation from long-term field trials, whereas the relevant mechanisms are still unknown. A long-term field experiment, including straw removal (CK), straw burning return (SBR), and straw return (SR) was conducted to investigate the starch structure, physicochemical properties, and cooked rice textures of indica early- and late-rice. Compared with CK, SBR and SR enhanced relative crystallinity, amylopectin long chains in both rice seasons, and gelatinization temperatures in late rice. Compared to SBR, SR decreased protein content and amylopectin short chains but increased starch branching degree, breakdown, and stickiness, ultimately contributing to improved starch thermal and pasting properties. Meanwhile, SR decreased hardness, cohesiveness, and chewiness, resulting in cooked texture meliorated, which was mainly attributed to amylopectin chain length and starch granule size. The results suggest that SR increased cooked texture of indica rice by altering starch structural and physicochemical properties.

3.
Int J Biol Macromol ; 252: 126455, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37633549

RESUMO

The starch multiscale structure, physiochemical properties, grain quality and cooked rice texture of high-quality early and late indica were analyzed under nitrogen panicle fertilizer (low panicle fertilizer, LPF; middle panicle fertilizer, MPF; high panicle fertilizer, HPF) treatments and their internal relations were investigated. Compared to the MPF treatment, the starch granules in HPF and LPF had more surface-proteins and irregular voids for high-quality early and late indica rice cultivars, respectively. Nitrogen panicle fertilization application increased amylopectin medium and long chains as well as protein content, resulting in higher relative crystallinity and gelatinization temperatures. Moderate changes in starch multistructures and physicochemical properties such as branching degree, amylopectin medium chain, and pasting viscosities derived from MPF treatment significantly improved processing, appearance qualities and cooked rice texture. Additionally, the decrease in starch branching, gelatinization temperatures, and granule uniformity along with an increase in large granules, breakdown, and △Hgel under MPF treatment were the main reasons for improving rice textural properties.


Assuntos
Oryza , Amido , Amido/química , Amilopectina/química , Oryza/química , Fertilizantes , Nitrogênio/metabolismo
4.
Food Res Int ; 164: 112320, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36737913

RESUMO

Late-season indica rice frequently encounters low temperature (LT) along with low light (LL) after heading in southern China, which deteriorates the grain quality by altering starch quality. However, the detailed effects on starch properties of these stressors remain unclear. Herein, two indica rice cultivars with good and poor grain quality were grown under control (CK), LT, and LT + LL conditions after heading and the structural and physicochemical properties of their starch were evaluated. Compared with CK, LT and LT + LL worsened thermal and pasting properties of starch in the two cultivars, mainly because they increased branch chain branching and A chain (DP ≤12), and decreased average branch chain length and crystallinity. Compared with LT, LT + LL deteriorated the pasting properties of the poor-quality cultivar, such as reducing breakdown (BD), final and peak viscosity, which mainly owing to decreasing the starch branching and crystallinity degrees, and increasing the small starch granules (d < 10 µm). Gelatinization enthalpy and BD both had significant and positive correlations with amylose content, the ratio of amylose and amylopectin, B3 chain and crystallinity. Taken together, these results suggest that LT and LT + LL during grain filling can deteriorate the physicochemical properties of starch in late-season indica rice cultivars by disrupting starch multilevel structure, especially upon LT + LL. In particular, while poor-quality cultivar had poorer physicochemical properties, the good-quality cultivar had poorer thermal properties under LT + LL.


Assuntos
Oryza , Amido , Amido/química , Amilose/análise , Oryza/química , Temperatura , Estações do Ano , Grão Comestível/química , China
5.
Artigo em Inglês | MEDLINE | ID: mdl-36497813

RESUMO

Given the prolonged nature of the COVID-19 pandemic and its long-term psychological impacts, this study aimed to explore how empathy leads to post-traumatic growth (PTG) among Chinese community workers. Guided by the revised PTG model, this study identified the relation between empathy and PTG using a multiple mediation model that included self-disclosure and social support as hypothesized mediators. This study utilized data from 414 Chinese adults aged 20 years or older who completed an online survey during the pandemic. Self-disclosure and social support were measured as mediating variables. The study variables were positively correlated with PTG. Empathy was positively correlated with self-disclosure and social support. After controlling for demographic covariates, the results indicated that self-disclosure and social support mediated the link between empathy and PTG in both parallel and sequential fashion. Empathy, self-disclosure, and social support played important roles in the growth of Chinese community workers. The present findings have been useful in increasing our understanding, policy programs, and interventions by governments or regional bodies to ameliorate community workers' PTG.


Assuntos
COVID-19 , Crescimento Psicológico Pós-Traumático , Adulto , Humanos , Pandemias , População do Leste Asiático , COVID-19/epidemiologia , Apoio Social , Adaptação Psicológica
6.
Carbohydr Polym ; 295: 119882, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35988987

RESUMO

Nitrogen management, especially panicle nitrogen fertilization (PNF), can affect cooked rice textures by altering starch quality, but the details are unclear. In this study, the starch multi-level structures, physicochemical properties and cooked rice textures of indica under different nitrogen managements were analysed and their internal relations were investigated. With an increase in PNF, large granules, amylopectin short chains, amylose content, thermal temperatures, setback, and hardness first exhibited decreasing trends and then increasing trends, which were relatively lower under moderate PNF (N3), whereas α-1,6 linkage, relative crystallinity, protein content, enthalpy of gelatinization (△Hgel), peak viscosity, breakdown and stickiness exhibited the opposite trends. N3 treatment significantly increased △Hgel and breakdown and decreased setback, hardness and chewiness, suggesting that it might contribute to better starch thermal stability and pasting properties, ultimately improving cooked rice texture. Nitrogen management affected the texture of cooked rice mainly by improving starch multi-level structures, thermal and pasting viscosities.


Assuntos
Oryza , Amido , Amilopectina/química , Amilose/química , Nitrogênio/metabolismo , Oryza/química , Amido/química , Viscosidade
7.
ACS Appl Mater Interfaces ; 14(21): 24875-24885, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35500233

RESUMO

Solid electrolyte interphase (SEI) is regarded as the key to developing stable and long-cycling lithium metal batteries (LMBs). The inevitable stress caused by the Li-metal anode expansion/contraction and the battery encapsulation is crucial to the SEI growth and properties. Herein, we perform reactive force field (ReaxFF) molecular dynamics simulations to investigate the structure and property variation of the pressure-induced SEI. The pressure boosts the SEI structure delamination and reduces the porosity based on the quantitative analysis of the charge spectrum and porous structure, which contributes to the formation of a thin and dense SEI. Meanwhile, the phase diagram combined with the pressure and salt concentration effects is established to obtain the proper trade-off between SEI mechanical and transport properties, demonstrating that the Li+ diffusion coefficients of the pressure-induced SEI can be improved by the high salt concentration when Young's modulus increases at the same time. The findings not only provide molecular insights into the SEI structure variation but also offer guidance and directions for optimizing the pressure-induced SEI property toward high-performance LMBs.

8.
Small Methods ; 5(6): e2100280, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34927898

RESUMO

Ion transport kinetics is identified as the major challenge of thick electrode design for high-energy-density lithium-ion batteries. The introduction of vertically-oriented structure pores, which provide fast transport pathways for Li+ , can maximize the rate-performance of electrodes while holding a high energy density. To overcome the harsh manufacturing requirements of traditional template-based methods for the oriented-pore electrodes, a template-free strategy is developed to meet the large-scale fabrication demand, in which controllable oriented microchannels are facilely constructed by vertically aggregated bubbles generated from thermal decomposition. The proposed method is demonstrated to be applicable for different active materials and compatible with industrial roll-to-roll manufacturing. The oriented-pore electrodes exhibit a seven times higher capacity at 5C rate and show double the power density relative to the state of the art while maintaining a high level of energy density. The balance between the ion transport kinetics through the channels and in the matrix manifests an optimal design of the electrode structures, enabling the desired superior performance of the electrodes toward practical applications.

9.
Food Chem ; 347: 129045, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33486361

RESUMO

The effects of water irrigation management including conventional irrigation (CK), constant flooding irrigation (CFI) and alternate wetting and drying (AWD) on starch structure and physicochemical properties of two indica rice cultivars with good- and poor-quality were evaluated in the field condition with two years. The results showed that AWD could significantly increase peak viscosity, breakdown and gelatinization temperature, decreased setback and gelatinization enthalpy in two indica rice cultivars. However, starch granule size and amylopectin chain length distribution were differed the trends in the rice cultivars and treatments. AWD reduced starch granules size and amylopectin short chain, especially for large starch granules, but increased medium and long chain, which might contribute to better thermal stability and pasting viscosity for good-quality cultivar. Our study indicated that water irrigation management affected starch structure and physicochemical properties of indica rice starch, and would provide favorable information for improvement of rice starch in food industry.


Assuntos
Oryza/química , Amido/química , Água/química , Amilopectina/química , Amilose/análise , Varredura Diferencial de Calorimetria , Oryza/metabolismo , Tamanho da Partícula , Proteínas de Plantas/análise , Temperatura , Viscosidade , Água/metabolismo
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