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1.
Braz. j. biol ; 84: e256565, 2024. tab, graf
Artigo em Inglês | LILACS-Express | MEDLINE, LILACSEXPRESS, LILACS, VETINDEX | ID: biblio-1360220

RESUMO

Abstract Liupan Mountains are an important region in China in the context of forest cover and vegetation due to huge afforestation and plantation practices, which brought changes in soil physio-chemical properties, soil stocks, and soil stoichiometries are rarely been understood. The study aims to explore the distribution of soil nutrients at 1-m soil depth in the plantation forest region. The soil samples at five depth increments (0-20, 20-40, 40-60, 60-80, and 80-100 cm) were collected and analyzed for different soil physio-chemical characteristics. The results showed a significant variation in soil bulk density (BD), soil porosity, pH, cation exchange capacity (CEC), and electric conductivity (EC) values. More soil BD (1.41 g cm-3) and pH (6.97) were noticed in the deep soil layer (80-100 cm), while the highest values of porosity (60.6%), EC (0.09 mS cm-1), and CEC (32.9 c mol kg-1) were reflected in the uppermost soil layer (0-20 cm). Similarly, the highest contents of soil organic carbon (SOC), total phosphorus (TP), available phosphorus (AP), total nitrogen (TN), and available potassium (AK) were calculated in the surface soil layer (0-20 cm). With increasing soil depth increment a decreasing trend in the SOC and other nutrient concentration were found, whereas the soil total potassium (TK) produced a negative correlation with soil layer depth. The entire results produced the distribution of SOCs and TNs (stocks) at various soil depths in forestland patterns were 0→20cm > 20→40cm > 40→60cm ≥ 60→80cm ≥ 80→100 cm. Furthermore, the stoichiometric ratios of C, N, and P, the C/P, and N/P ratios showed maximum values (66.49 and 5.46) in 0-20 cm and lowest values (23.78 and 1.91) in 80-100 cm soil layer depth. Though the C/N ratio was statistically similar across the whole soil profile (0-100 cm). These results highlighted that the soil depth increments might largely be attributed to fluctuations in soil physio-chemical properties, soil stocks, and soil stoichiometries. Further study is needed to draw more conclusions on nutrient dynamics, soil stocks, and soil stoichiometry in these forests.


Resumo As montanhas de Liupan são uma região importante na China no contexto de cobertura florestal e vegetação devido às enormes práticas de florestamento e plantação, que trouxeram mudanças nas propriedades físico-químicas do solo, e estoques e estequiometrias do solo raramente são compreendidos. O estudo visa explorar a distribuição de nutrientes do solo a 1 m de profundidade do solo na região da floresta plantada. As amostras de solo em cinco incrementos de profundidade (0-20, 20-40, 40-60, 60-80 e 80-100 cm) foram coletadas e analisadas para diferentes características físico-químicas do solo. Os resultados mostraram uma variação significativa nos valores de densidade do solo (BD), porosidade do solo, pH, capacidade de troca catiônica (CEC) e condutividade elétrica (CE). Mais DB do solo (1,41 g cm-3) e pH (6,97) do solo foram observados na camada profunda do solo (80-100 cm), enquanto os maiores valores de porosidade (60,6%), CE (0,09 mS cm-1) e CEC (32,9 c mol kg-1) foram refletidos na camada superior do solo (0-20 cm). Da mesma forma, os maiores teores de carbono orgânico do solo (SOC), fósforo total (TP), fósforo disponível (AP), nitrogênio total (TN) e potássio disponível (AK) foram calculados na camada superficial do solo (0-20 cm). Com o aumento do incremento da profundidade do solo, uma tendência decrescente no SOC e na concentração de outros nutrientes foi encontrada, enquanto o potássio total do solo (TK) produziu uma correlação negativa com a profundidade da camada do solo. Todos os resultados produziram a distribuição de SOCs e TNs (estoques) em várias profundidades de solo em padrões de floresta 0 → 20cm> 20 → 40cm> 40 → 60cm ≥ 60 → 80cm ≥ 80 → 100 cm. Além disso, as relações estequiométricas de C, N e P, as relações C / P e N / P, apresentaram valores máximos (66,49 e 5,46) em 0-20 cm, e valores mais baixos (23,78 e 1,91) em solo de 80-100 cm profundidade da camada. Embora a relação C / N fosse estatisticamente semelhante em todo o perfil do solo (0-100 cm). Esses resultados destacaram que os incrementos de profundidade do solo podem ser amplamente atribuídos a flutuações nas propriedades físico-químicas do solo, estoques e estequiometrias do solo. Mais estudos são necessários para tirar conclusões adicionais sobre a dinâmica dos nutrientes, estoques de solo e estequiometria do solo nessas florestas.

2.
Braz. j. biol ; 83: e246889, 2023. tab, graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1285639

RESUMO

Abstract The intertidal rocky shores in continental Chile have high species diversity mainly in northern Chile (18-27° S), and one of the most widespread species is the gastropod Echinolittorina peruviana (Lamarck, 1822). The aim of the present study is do a first characterization of spatial distribution of E. peruviana in along rocky shore in Antofagasta town in northern Chile. Individuals were counted in nine different sites that also were determined their spectral properties using remote sensing techniques (LANDSAT ETM+). The results revealed that sites without marked human intervention have more abundant in comparison to sites located in the town, also in all studied sites was found an aggregated pattern, and in six of these sites were found a negative binomial distribution. The low density related to sites with human intervention is supported when spectral properties for sites were included. These results would agree with other similar results for rocky shore in northern and southern Chile.


Resumo As costas rochosas entremarés no Chile continental apresentam alta diversidade de espécies, principalmente no norte do país (18-27 ° S), e uma das espécies mais difundidas é o gastrópode Echinolittorina peruviana (Lamarck, 1822). O objetivo do presente estudo é fazer uma primeira caracterização da distribuição espacial de E. peruviana no costão rochoso da cidade de Antofagasta no norte do Chile. Os indivíduos foram contados em nove locais diferentes onde também foram determinadas suas propriedades espectrais usando técnicas de sensoriamento remoto (LANDSAT ETM +). Os resultados revelaram que os locais sem intervenção humana marcada apresentam maior abundância em comparação aos locais localizados no município. Também em todos os locais estudados foi encontrado um padrão agregado, sendo que em seis desses locais foi encontrada uma distribuição binomial negativa. A baixa densidade relacionada a sites com intervenção humana é suportada quando as propriedades espectrais para sites foram incluídas. Esses resultados concordariam com outros resultados semelhantes para costões rochosos no norte e no sul do Chile.


Assuntos
Humanos , Animais , Ecossistema , Gastrópodes , Chile
3.
Asia Pac J Oncol Nurs ; 9(3): 179-184, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35494092

RESUMO

Objective: Cancer predisposition perception refers to the subjective estimation of the likelihood of being diagnosed with cancer in the future. It affects people's behavior concerning cancer screening and prevention. At present, there is no available tool to evaluate cancer predisposition perception. The aim of this study was to translate the cancer predisposition perception scale into simplified Chinese (C-CPPS), and then test its psychometric properties among Chinese patients. Methods: In phase I, the CPPS was translated into Chinese, and validated by an expert panel. In phase II, data on reliability and validity was evaluated in terms of construct validity, criterion validity, internal consistency, test-retest reliability, and item-total correlations, with a convenience sample of 208 patients recruited from the colorectal cancer surgical ward. Results: The C-CPPS had desirable validity and reliability. The scale-level content validity index was 0.96. Exploratory factor analysis indicated that the six-factor structure of the C-CPPS was good fit to the data. Correlation between the C-CPPS and the Brief Illness Perception Questionnaire was statistically significant. Cronbach's α for the entire scale was 0.90 and 0.71-0.95 for five of the six subscales. Item-total correlations ranged from 0.309 to 0.775, and the intraclass correlation coefficient was 0.97. Conclusions: The C-CPPS appears to be culturally appropriate, reliable, and valid for assessing cancer predisposition perception among patients with colorectal cancer in China.

4.
Braz. j. oral sci ; 21: e224265, jan.-dez. 2022. tab
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1354719

RESUMO

Aim: This study assessed the color and translucency stability of a polymer infiltrated ceramic network (PICN) and compared it with a resin composite (RC) and a feldspathic ceramic (FEL). Methods: Disc-shaped samples of a PICN (Vita Enamic), a feldspathic ceramic (Vitablocks Mark II), and a resin composite (Brava block) were prepared from CAD/CAM blocks. PICN and RC surfaces were finished with a sequence of polishing discs and diamond paste. FEL samples received a glaze layer. The samples were subjected to 30-min immersions in red wine twice a day for 30 days. CIEL*a*b* coordinates were assessed with a spectrophotometer at baseline and after 15 and 30 days of immersion. Color alteration (ΔE00) and translucency parameter (TP00) were calculated with CIEDE2000. Average roughness was measured before the staining procedures. Color difference and translucency data were analyzed with repeated-measures ANOVA and Tukey's tests. Roughness was analyzed with the Kruskal-Wallis test. Results: Roughness was similar among the experimental groups. All materials had their color alteration significantly increased from 15 to 30 days of staining. PICN reached an intermediate ΔE00 between FEL and RC at 15 days. PICN revealed a color alteration as high as the composite after 30 days. No statistical difference was observed regarding translucency. Conclusion: PICN was not as color stable as the feldspathic ceramic at the end of the study. Its color alteration was comparable to the resin composite when exposed to red wine. However, the translucency of the tested materials was stable throughout the 30-day staining


Assuntos
Propriedades de Superfície , Teste de Materiais , Cerâmica , Desenho Assistido por Computador , Cor , Resinas Compostas
5.
Braz. j. oral sci ; 21: e226262, jan.-dez. 2022. ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1354997

RESUMO

Aim: To evaluate the impact of a dual-cured adhesive system on the in situ degree of conversion (DC), bond strength (BS) and failure mode (FM) of adhesive interfaces in dentin cavities restored with a bulk-fill resin composite. Methods: 4-mm-deep dentin cavities with a 3.1 C-factor were created in 68 bovine incisors (n = 17 per group). The lightcured (Scotchbond™ Universal) or the dual-cured (Adper™ Scotchbond™ Multi-purpose Plus) adhesive system was applied to the cavities, which were then restored with a bulkfill resin composite (Filtek™ Bulk Fill). In situ DC analysis was performed by means of micro Raman spectroscopy at the top and bottom interfaces. Push-out BS was measured in a universal testing machine after 24-h or 6-month water storage. FM was determined with a stereomicroscope. Data of in situ DC and BS were analyzed by two-way analysis of variance (ANOVA) and Tukey test (p<0.05), while the FM was analyzed descriptively. Results: The groups that received the dual-cured adhesive system showed statistically higher in situ DC and BS than those that received the light-cured adhesive system. Cohesive failure mode was the most frequent in all conditions. Conclusion: In situ DC and BS were influenced by the curing strategies of the adhesive systems with better performance of the dual-cured material


Assuntos
Envelhecimento , Adesivos Dentinários , Resinas Compostas , Propriedades Físicas , Polimerização
6.
Food Chem ; 393: 133293, 2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35653992

RESUMO

In the current study, the physicochemical and emulsifying properties of modified waxy maize starch obtained through a new environmentally friendly method of esterification were evaluated. The starch modification was carried out in NaOH solution with different levels of octanoyl, myristoyl, and stearoyl chlorides. Increasing the fatty acid chlorides concentration led to the degree of substitution increment, while reaction efficiency and yield decreased. Based on fourier transform infrared spectroscopy results, the presence of two new bands of carbonyl (1740-1750 cm-1) and carboxyl (1570 cm-1) groups in the ester bond confirmed the successful starch esterification process. The level of 0.1 mL fatty acid chlorides/g of starch demonstrated the highest emulsifying properties. Upon esterification, the crystalline structure of amylopectin was destroyed, indicating no gelatinization features. Therefore, using the fatty acid chlorides in an alkaline condition could be suggested as a feasible way to modify waxy maize starch toward hydrophobicity increment with desirable properties.

7.
Int J Clin Health Psychol ; 22(3): 100315, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35662789

RESUMO

Background/Objective: The aim of the present study was to compare competing psychometric models and analyze measurement invariance of the Hospital Anxiety and Depression Scale (HADS) in cancer outpatients. Method: The sample included 3,260 cancer outpatients. Latent structure of the HADS was analyzed using confirmatory factor analysis (CFA) with robust maximum likelihood estimation (MLR). Measurement invariance was tested for age, time of response, gender, and cancer type by comparing nested multigroup CFA models with parameter restrictions. Results: Except for the one-factor solutions, all models showed acceptable model fit and measurement invariance. The model with the best fit was the originally proposed two-factor model with exclusion of two items. The one-factor solutions showed inacceptable model fit and were not invariant for age and gender. Conclusions: The HADS has a robust two-factor structure in cancer outpatients. We recommend excluding item 7 and 10 when screening for anxiety and depression.

8.
J Comput Phys ; 463: 111266, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35662800

RESUMO

Image-based computational models of the heart represent a powerful tool to shed new light on the mechanisms underlying physiological and pathological conditions in cardiac function and to improve diagnosis and therapy planning. However, in order to enable the clinical translation of such models, it is crucial to develop personalized models that are able to reproduce the physiological reality of a given patient. There have been numerous contributions in experimental and computational biomechanics to characterize the passive behavior of the myocardium. However, most of these studies suffer from severe limitations and are not applicable to high-resolution geometries. In this work, we present a novel methodology to perform an automated identification of in vivo properties of passive cardiac biomechanics. The highly-efficient algorithm fits material parameters against the shape of a patient-specific approximation of the end-diastolic pressure-volume relation (EDPVR). Simultaneously, an unloaded reference configuration is generated, where a novel line search strategy to improve convergence and robustness is implemented. Only clinical image data or previously generated meshes at one time point during diastole and one measured data point of the EDPVR are required as an input. The proposed method can be straightforwardly coupled to existing finite element (FE) software packages and is applicable to different constitutive laws and FE formulations. Sensitivity analysis demonstrates that the algorithm is robust with respect to initial input parameters.

9.
Food Chem X ; 14: 100347, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35663599

RESUMO

Texture characteristics of quinoa under microwave (MW) irradiation were studied from the perspective of starch gelatinization. MW reduced the light transmittance and increased the hardness and stickiness of quinoa. Microstructure showed that MW dispersed the vesicular structure of starch aggregates into separate starch particles, resulting in the full hydration of starch and water molecules to form denser network structures. The value of peak viscosity and setback decreased in RVA after MW treatment, but the gelatinization temperature remained stable. DSC further proved that moderate MW treatment could reduce the gelatinization enthalpy of starch and made quinoa accessible to gelatinize. However, XRD showed that the crystal structure of starch was preserved, but the crystallinity increased. Finally, low field NMR showed that moderate MW stimulated the full hydration of starch to form denser network structures, while excessive MW treatment made starch partially gelatinize and form rigid structure, resulting in negative texture properties.

10.
Eur J Midwifery ; 6: 30, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35664015

RESUMO

INTRODUCTION: A higher degree of midwives' empowerment is associated with greater job satisfaction and better midwifery care outcomes for women and their families. Empowered midwives are able to better empower women who in turn have a positive influence on the midwives' empowerment. The aim of this study was the translation, cultural adaptation, and validation of the perceptions of empowerment in midwifery scale-revised (PEMS-R) in a group of Italian midwives. METHODS: The World Health Organization (WHO) method was adopted to achieve the PEMS-R Italian version. This process involved five steps: 1) forward translation, 2) expert panel translation, 3) back-translation, 4) pre-testing and cognitive interviewing, and 5) final version. The test's internal consistency and validity were assessed by following international guidelines. Internal consistency was examined through Cronbach's alpha (α) coefficient. RESULTS: The PEMS-R-IT was administered to 147 Italian midwives from northern Italy. Factor analysis of the 19 items, extracted 4 factors that explained 74.96% of the variance. The Student's t-test for independent samples was used to identify a possible correlation between a higher/lower perception of empowerment and: 1) the education level, and 2) the years of experience of recruited midwives. No statistically significant differences were obtained in either case. The PEMS-R-IT was found to have a good internal consistency for each of its 4 subscales. CONCLUSIONS: The PEMS-R-IT is a valid and reliable tool, useful to assess midwives' empowerment. It can be used in both clinical practice and research in order to investigate the level of empowerment of midwives within the Italian national context.

11.
Small ; : e2203033, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35665598

RESUMO

In vivo, natural biomaterials are frequently anisotropic, exhibiting directional microstructures and mechanical properties. It remains challenging to develop such anisotropy in synthetic materials. Here, a facile one-step approach for in situ fabrication of hydrogels with hierarchically anisotropic architectures and direction-dependent mechanical properties is proposed. The anisotropic hydrogels, composed of a fibrous gel network (0.1 wt%), cross-linked with magnetic nanoparticles (spheres, rods, and wires, <0.1 wt%) are readily formed in the presence of very low magnetic fields (<20 mT). The anisotropy of the nanoparticles is transduced to the polymer network, leading to macroscopic anisotropy, for instance, in mechanical properties. Electrostatic repulsion by the negatively charged nanoparticles induces an additional layer of order in the material, perpendicular to the magnetic field direction. The straightforward fabrication strategy allows for stepwise deposition of layers with different degrees or directions of anisotropy, which enables the formation of complex structures that are able to mimic some of the complex hierarchical architectures found in biology. It is anticipated that this approach of hydrogel alignment may serve as a guide for designing advanced biomaterials in tissue engineering.

12.
Artigo em Inglês | MEDLINE | ID: mdl-35666942

RESUMO

Exploring high performance and excellent ambient stability in two-dimensional (2D) monolayer photoelectric materials is motivated by not only practical applications but also scientific interest. Here, a new 2D monolayer W8Se12 structure is synthesized via in situ electron-beam irradiation on 2D WSe2. Moreover, we systematically studied the photoelectric properties of the class of monolayer M8X12 (M = Mo, W; X = S, Se, and Te) materials by first principles. The results indicated that Mo8S12, Mo8Se12, W8S12, and W8Se12 monolayers possess desirable direct band gaps and remarkable anisotropic optical absorption in visible light, while Mo8Te12 and W8Te12 monolayers are metals. Impressively, the monolayer W8Se12 can result in a direct-indirect-metal transition under uniaxial strain. In addition, they show high anisotropic carrier mobilities (up to 104 cm2 V-1 s-1), significantly over those of transition-metal dichalcogenides. These new binary monolayer M8X12 structures can effectively broaden the 2D material family and may provide four potential candidates in photoelectric applications.

13.
J Plant Growth Regul ; : 1-17, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35668726

RESUMO

Previous studies have shown the great potential of using plasma-activated water (PAW) on improving agriculture seed germination, however, information on the influence of PAW on crop plantlet juice remains scanty. In this research, the effect of PAW generated by atmosphere pressure Ar-O2 plasma jet for 1-5 min on wheat seed germination, seedling growth and nutritional properties of wheat plantlet juice was investigated. Results revealed that all PAWs could enhance wheat seed germination and seedling growth in 7 days by improving the germination rate, germination index, fresh weight, dry weight and vigour index, and especially that PAW activated for 3 min (PAW-3) showed the best overall performance. In addition, the application of PAWs enhanced the nutritional properties of wheat plantlet juice from those grown for 14 days by improving total soluble solids, protein content, photosynthetic pigments, total phenolic content, antioxidant activity, enzyme activity, free amino acids and minerals content, and the best enhancement was also observed in PAW-3. It was concluded that PAWs would be an effective technique to enhance the growth and nutritional properties of crop sprouts, which could be served as functional foods in many forms. Supplementary Information: The online version contains supplementary material available at 10.1007/s00344-022-10677-3.

14.
Regen Biomater ; 9: rbac009, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35668923

RESUMO

The immune system protects organisms against endogenous and exogenous harm and plays a key role in tissue development, repair and regeneration. Traditional immunomodulatory biologics exhibit limitations including degradation by enzymes, short half-life and lack of targeting ability. Encapsulating or binding these biologics within biomaterials is an effective way to address these problems. Hydrogels are promising immunomodulatory materials because of their prominent biocompatibility, tuneability and versatility. However, to take advantage of these opportunities and optimize material performance, it is important to more specifically elucidate, and leverage on, how hydrogels affect and control the immune response. Here, we summarize how key physical and chemical properties of hydrogels affect the immune response. We first provide an overview of underlying steps of the host immune response upon exposure to biomaterials. Then, we discuss recent advances in immunomodulatory strategies where hydrogels play a key role through (i) physical properties including dimensionality, stiffness, porosity and topography; (ii) chemical properties including wettability, electric property and molecular presentation;and (iii) the delivery of bioactive molecules via chemical or physical cues. Thus, this review aims to build a conceptual and practical toolkit for the design of immune-instructive hydrogels capable of modulating the host immune response.

15.
Food Chem ; 393: 133397, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35679704

RESUMO

This study aimed to investigate physicochemical, functional and antioxidant properties of mung bean protein (MBP) enzymatic hydrolysates (MBPEHs) by alcalase, neutrase, protamex, flavourzyme and papain. Physicochemical properties were evaluated by SDS-PAGE, particle size distribution, FTIR, ultraviolet visible and fluorescence spectrophotometries. ABTS, hydroxyl scavenging, Fe2+ chelating activity were used to evaluate antioxidant activity. Enzymolysis with five proteases decreased average particle size, α-helix, ß-sheet, surface hydrophobicity of hydrolysates. Alcalase hydrolysate had the highest degree of hydrolysis (23.55%), absolute zeta potential (33.73 mV) and the lowest molecular weight (<10 kDa). Protamex and papain hydrolysates had higher foaming capacities, emulsification activity indexes, emulsion stability indexes (235.00%, 123.07 m2/g, 132.54 min; 200.10%, 105.39 m2/g, 190.67 min) than MBP (135.03%, 20.03 m2/g, 30.88 min). Alcalase hydrolysate demonstrated the lowest IC50 (mg/mL) in ABTS (0.12), hydroxyl (2.98), Fe2+ chelating (0.22). These results provide support for application of MBPEHs as foaming agent, emulsifier and antioxidant in food industry.

16.
Disabil Rehabil ; : 1-10, 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35680400

RESUMO

PURPOSE: We aimed to translate and cross-culturally adapt the Western Ontario Rotator Cuff index into Greek (WORC-GR) and evaluate its reliability and validity in a Greek speaking population with rotator cuff (RC) disorders. MATERIALS AND METHODS: Translation and cross-cultural adaptation process followed published guidelines. Content and face validity were assessed by 9 experts and 16 patients with RC pathologies, respectively. Internal structure, reliability, measurement error, and convergent validity (correlation with the Disability of the Arm, Shoulder and Hand - DASH, Shoulder Pain and Disability Index - SPADI, and Short Form-36) of the index were evaluated in 104 participants (44.2% women, mean age ± SD: 44.9 ± 15.01 years) with RC related pain. RESULTS: The WORC-GR showed excellent item and scale content validity index (0.875-1.00 and 0.975, respectively), internal consistency (Cronbach's alpha range 0.749 - 0.903) and test-retest reliability (intraclass correlation coefficient: 0.942, 95% CI: 0.913-0.961). Factorial validity testing revealed a 4-factor structure explaining 69.7% of the total variance. High positive correlations were found with DASH (r = 0.806) and SPADI (r = 0.852). CONCLUSIONS: WORC-GR is a reliable and valid instrument to assess symptoms in patients with RC disorders. Further research on the content validity, internal structure, and responsiveness of the tool is required. Implications for rehabilitationThe Greek version of WORC (WORC-GR) is a clear and comprehensible patient reported outcome measure.WORC-GR has excellent internal consistency, test-retest reliability and with no floor and ceiling effects.WORC-GR is a valid outcome measure for patients with rotator cuff disorders.

17.
Foods ; 11(11)2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35681287

RESUMO

The aim of this study is to establish the dry aging period of beef loin in an electric field refrigeration system. Beef loins (Korea quality grade 2) were dry aged at 0, -1, and -2 °C temperature in an electric field refrigeration system (air velocity, 5 ± 2 m/s) and aging stopped as the value of TPC reached 7 log CFU/g. Samples were examined by aging yield, trimming yield, pH, color, water holding capacity (WHC), cooking yield, shear force, total plate count (TPC), 2-thiobarbituric acid reactive substances (TBARS), and volatile basic nitrogen (VBN). The results for aging yield, trimming yield, redness, yellowness, and chroma decreased with increasing the dry aging period. Contrariwise, those for pH, lightness, hue angle, WHC, and cooking yield increased with the dry aging period. In shear force, the lowest value occurred at four weeks at all temperatures. The results for TPC, TBARS, and VBN increased with aging period, and VBN at 6 weeks at 0 °C and 9 weeks at -1 °C exceed the standard value (20 mg/100 g), while dry aging temperature had an effect on physico-chemical and storage properties by lower temperatures showed slower progress. Therefore, dry aging on an electric field refrigerate system can be used until 4 weeks at 0 °C, 8 weeks at -1 °C, and 10 weeks at -2 °C. However, considering physico-chemical properties, 4 weeks at every temperature is suitable for manufacturing soft dry-aged beef loin.

18.
Foods ; 11(11)2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35681294

RESUMO

Instant flavor peanut powder is a nutritional additive that can be added to foods to impart nutritional value and functional properties. Sensory acceptability is the premise of its development. Flavor is the most critical factor in sensory evaluation. The heat treatment involved in peanut processing is the main way to produce flavor substances and involves chemical reactions: Maillard reaction, caramelization reaction, and lipid oxidation reaction. Peanut is rich in protein, fat, amino acids, fatty acids, and unsaturated fatty acids, which participate in these reactions as volatile precursors. N-heterocyclic compounds, such as the pyrazine, are considered to be the key odorants of the "baking aroma". However, heat treatment also affects the functional properties of peanut protein (especially solubility) and changes the nutritional value of the final product. In contrast, functional properties affect the behavior of proteins during processing and storage. Peanut protein modification is the current research hotspot in the field of deep processing of plant protein, which is an effective method to solve the protein denaturation caused by heat treatment. The review briefly describes the characterization and mechanism of peanut flavor during heat treatment combined with solubilization modification technology, proposing the possibility of using peanut meal as material to produce IFPP.

19.
Foods ; 11(11)2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35681304

RESUMO

Improving the technological functionality of climate-resilient crops (CRCs) to promote their use in staple foods, such as bread, is relevant to addressing food and nutrition security in Africa. Dry heating of cowpea flour (CPF) was studied as a simple technology to modulate CPF physicochemical properties in relation to bread applications. For this purpose, the melting behavior of cowpea starch and proteins in CPF was first studied and modeled using Flory-Huggins theory for polymer melting. Next, dry-heating conditions were investigated based on the predicted biopolymer melting transitions in CPF to be well below starch and protein melting. The pasting properties (i.e., peak viscosity, final viscosity, breakdown and setback) of CPF could be selectively modulated depending on temperature-time combinations without altering the thermal behavior (i.e., melting enthalpies) of CPF. Water-binding capacity and soluble solids decreased with the increased severity of the temperature-time combinations. Dry-heated CPF added to CRC-based bread significantly improved crumb texture. In particular, dry heating at 100 °C for 2 h provided bread with the highest crumb softness, cohesiveness and resilience. The positive effects on the crumb texture could be largely related to enhanced starch integrity, as indicated by a reduction in breakdown viscosity after treatment. Overall, dry heating of CPF under defined conditions is a promising technology for promoting the use of CPF as a techno-functional and protein-rich ingredient in bread-type products.

20.
Foods ; 11(11)2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35681305

RESUMO

Dairy and plant-based proteins are widely utilized in various food applications. Several techniques have been employed to improve the techno-functional properties of these proteins. Among them, pulsed electric field (PEF) technology has recently attracted considerable attention as a green technology to enhance the functional properties of food proteins. In this review, we briefly explain the fundamentals of PEF devices, their components, and pulse generation and discuss the impacts of PEF treatment on the structure of dairy and plant proteins. In addition, we cover the PEF-induced changes in the techno-functional properties of proteins (including solubility, gelling, emulsifying, and foaming properties). In this work, we also discuss the main challenges and the possible future trends of PEF applications in the food proteins industry. PEF treatments at high strengths could change the structure of proteins. The PEF treatment conditions markedly affect the treatment results with respect to proteins' structure and techno-functional properties. Moreover, increasing the electric field strength could enhance the emulsifying properties of proteins and protein-polysaccharide complexes. However, more research and academia-industry collaboration are recommended to build highly effective PEF devices with controlled processing conditions.

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