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1.
Environ Monit Assess ; 192(2): 151, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32002692

RESUMO

The present study was conducted to identify the minimum number of sampling points to monitor surface hardness of the pitches through geostatistical methods and to determine spatial and temporal distribution of surface hardness in autumn, winter, spring, and summer periods. Initial samplings were performed from 126 points and with data reduction, the optimum number of sampling points was identified as 77. In upcoming sampling periods, surface hardness and soil temperature were directly measured in situ and disturbed soil samples taken from 77 points were subjected to moisture content, bulk density, and texture analyses (clay-C, silt-Si, and sand-S). In autumn period, surface hardness highly correlated with soil temperature and moisture content (r2 = - 0.438 and - 0.344, p < 0.01). Surface hardness significantly correlated only with soil temperature in winter period and only with bulk density in summer period (respectively r2 = - 0.366 and 0.234, p < 0.01). Average surface hardness values in autumn, winter, spring, and summer periods were respectively measured as 5.99, 6.55, 5.84, and 5.92%. Semivariograms generated for hardness were modeled with spherical model in all periods and a certain nugget effect was detected in all periods. Maximum likelihood distance for autumn, winter, spring, and summer periods was respectively measured as 65, 40, 45, and 46 m. It was concluded based on present findings that geostatistical methods could reliably be used to monitor surface hardness of football pitches and then proper and timely interventions could be made to sections not complying with FIFA standards.


Assuntos
Monitoramento Ambiental , Solo , Futebol Americano , Dureza , Estações do Ano
2.
Eur J Prosthodont Restor Dent ; 28(1): 28-35, 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32057198

RESUMO

The purpose of this study was to evaluate two-body wear and hardness of new generation artificial resin teeth. Ten specimens of four different artificial resin teeth (nanofill composite, nanohybrid composite, microfiller reinforced acrylic and highly modified acrylic) were prepared. Specimens were thermodynamically loaded in a dual-axis chewing simulator (50N, 240,000 cycles, 1.6 Hz, 5/55°C thermocycle). The wear loss was analyzed by using plaster replicas and 3D laser scanner. Vickers hardness was determined before and after thermodynamic loading. Mean Vickers hardness values of highly modified acrylic resin teeth were statistically significantly lower than nanohybrid composite (p⟨0.001), nanofilled composite (p⟨0.001) and microfiller reinforced acrylic resin teeth (p⟨0.001). Mean wear loss of highly modified and microfiller reinforced acrylic resin teeth were statistically significantly lower than nanohybrid composite (p⟨0.001) and nanofilled composite (p⟨0.001) resin teeth. There was a statistically significant difference in wear among the materials. The correlation between hardness and wear was not statistically significant.


Assuntos
Resinas Compostas , Desgaste de Restauração Dentária , Porcelana Dentária , Análise do Estresse Dentário , Dureza , Teste de Materiais , Propriedades de Superfície , Dente Artificial
3.
J Biol Regul Homeost Agents ; 34(1 Suppl. 1): 39-47, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32064834

RESUMO

The aim of this study is to evaluate the micro hardness Vickers of a composite micro hybrid polymerized under constant pressure. Twelve experimental samples were made equally divided into two groups: an experimental group and a control. Enamel plus HRi (Micerium) microbiotic composite resin, UD3 colour, was inserted into a syringe heater (ENA HEAT Composite Heating Conditioner) so that the material could be brought to a temperature of 39°C. A defined amount of composite resin is taken from the syringe with a Heidemann spatula and placed between two slides, previously cleaned with 90 ° alcohol. The samples are then inserted one at a time into a special device for constant pressure application. Vickers hardness measurements were made on the top of surfaces. The mean value of the samples belonging to the experimental group is 56.81 ± 0.71. The mean value of the control samples is 52.02 ± 2. The results obtained allow us to state that applying a constant pressure during the cementation phase of indirect adhesive restorations allows to obtain better mechanical characteristics of the composite used as a cementing agent.


Assuntos
Resinas Compostas , Materiais Dentários , Cura Luminosa de Adesivos Dentários , Teste de Materiais , Dureza , Pressão , Propriedades de Superfície
4.
J Oral Sci ; 62(1): 48-51, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31996522

RESUMO

Although there have been improvements in bracket systems precoated with adhesive, removal of adhesive remnants continues to be problematic. This study compared the hardness and maintainability of precoated adhesive with other commercial adhesives. Knoop hardness values were measured after light- or chemical-induced initial curing, immersion in distilled water at 37°C for 24 h and 1,000 and 10,000 thermal cycles after 24 h. Additionally, the forces required to move brackets by 0.5 mm were measured during bracket positioning, and brackets bonded to bovine enamel were examined by field-emission scanning electron microscopy. The Knoop hardness values of the precoated adhesives were lower than those of commercial resin composite adhesives, and hardness was dependent on the amount of filler in the resin matrix. The ability to maintain the device position may depend on the resin matrix composition. Precoated adhesives with less filler and more matrix material are light curable, and remnant resin may be easily removed.


Assuntos
Colagem Dentária , Braquetes Ortodônticos , Ataque Ácido Dentário , Adesivos , Animais , Bovinos , Cimentos Dentários , Dureza , Teste de Materiais , Cimentos de Resina , Propriedades de Superfície
5.
J Sci Food Agric ; 100(3): 1238-1245, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31696519

RESUMO

BACKGROUND: Maize tortilla staling is a major drawback that affects its commercialization and consumption, and so novel methods for retarding staling are continuously being explored. The present study evaluated the effect of adding a canola oil/candelilla wax oleogel (CWO; 0. 2, 4 and 6 g 100 g-1 ) to a basic masa formulation (water, 60 g 100 g-1 ; nixtamalized maize flour, 40 g 100 g-1 ) on the texture, staling and in vitro starch digestibility of maize tortillas made using a hot plate (200 °C). RESULTS: Textural analysis showed that CWO reduced hardness and increased the tensile strength of tortillas. Fourier transform infrared analysis indicated that the retrogradation of starch chains, quantified in terms of the intensity ratio 1047/1022, was reduced by oleogel incorporation. In vitro starch digestibility tests showed that tortillas containing CWO had lower readily digestible and slowly digestible starch fractions compared to the control tortilla without oleogel. CONCLUSION: The formation of amylose-lipid inclusion complexes and the formation of an oily physical barrier around starch granules were postulated as mechanisms underlying the reduced starch digestibility. © 2019 Society of Chemical Industry.


Assuntos
Pão/análise , Euphorbia/química , Aditivos Alimentares/análise , Óleo de Brassica napus/química , Amido/química , Ceras/análise , Zea mays/química , Digestão , Farinha/análise , Manipulação de Alimentos , Qualidade dos Alimentos , Dureza , Humanos , Compostos Orgânicos/química , Amido/metabolismo , Paladar , Zea mays/metabolismo
6.
Dent Mater ; 36(1): 25-42, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31543376

RESUMO

OBJECTIVE: Overview the development of human tooth; enamel, dentoenamel junction and dentin in regard to hierarchical structure property relationships and how these component structures can serve as templates for the design of tough materials. METHODS: The dental, engineering and ceramic literature (PubMed, Science Direct, Google Scholar) covering the last 20years was over viewed regarding enamel and dentin characterization, structure-property studies, as well as, publications related to bioinspired materials with relationship to tooth structure. Relevant publications were selected for inclusion. RESULTS: Enamel has been studied and modelled at 3 hierarchical levels, prism structure, parallel prism interactions and enamel decussation effects. Missing is a 4th level where the previous three hierarchies are combined with the 3D arrangement of these levels in enamel areas. Aspects of the enamel prism infrastructure and prism decussation have been used in 3D printing of Bouligand ceramic structures. The dento-enamel junction serves to arrest cracks and reduce the stress in enamel as a graded elastic modulus layer, leading to development of dental ceramics with increased strength and fatigue resistance. Dentin is a compliant structure that supports enamel mechanically and may, through providing interstitial fluid at the DEJ, allow repair of microcracks in enamel. Adequate models of dentin properties remain to be developed as it remains highly variable in tubule lumen size and the degree of mineral density around and between tubules. SIGNIFICANCE: The structure of teeth, particularly the 4 hierarchical levels of enamel, creates a vital, hard, tough damage tolerant system for inspiring new materials.


Assuntos
Materiais Biomiméticos , Dente , Esmalte Dentário , Dentina , Dureza , Humanos
7.
Int Endod J ; 53(2): 250-264, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31489641

RESUMO

AIM: To compare the mechanical properties and metallurgic features of new and used Reciproc Blue and Reciproc instruments. METHODOLOGY: A total of 120 R25 Reciproc Blue and R25 Reciproc instruments were used. The morphological, chemical, mechanical, thermal and phase composition characteristics of new and ex vivo used files were investigated by scanning electron microscopy (FEG-SEM) with energy dispersive X-ray spectroscopy (EDS), focused ion beam analysis (FIB), micro-Raman spectroscopy, FEG-SEM metallography, X-ray diffraction (XRD), differential scanning calorimetry (DSC) and indentation tests. Usage-induce degradation was evaluated. Ten new and ten used instruments per type were run until fracture occurred in a stainless steel artificial canal (60° angle of curvature, 4-mm radius). Time to fracture and the length of the fractured fragment were recorded. Torque and angle of rotation at failure of ten new and ten used instruments for each type were measured according to ISO 3630-1. The fracture surface of each fragment was examined. Two-way analyses of variance was used to analyse the data statistically (α-level 0.05). RESULTS: SEM analysis revealed microcracks near the tip on both files after ex vivo usage tests. FIB imaging and micro-Raman spectroscopy confirmed the presence of an oxide layer on the Reciproc Blue surface. There was no thinning of the coating after use. XRD revealed a reduction of martensite and R-phase in Reciproc Blue after use. DSC analysis revealed different transformation temperatures for the instruments analysed. Reciproc Blue was significantly more flexible than Reciproc for both new and used samples (P < 0.05), and they were significantly more resistant to cyclic fatigue than Reciproc (P < 0.05). Ex vivo usage reduced the fatigue resistance of both files. Torsional resistance of Reciproc and Reciproc Blue was not reduced by simulated use (P > 0.05). CONCLUSIONS: The thermal treatment of Reciproc Blue was associated with a finer structure with smaller grains than Reciproc, which increased its fracture resistance and was also responsible for its reduced hardness and lower elastic modulus. Both files were safe during ex vivo usage in severely curved canals.


Assuntos
Metalurgia , Preparo de Canal Radicular , Desenho de Equipamento , Falha de Equipamento , Dureza , Teste de Materiais , Estresse Mecânico , Propriedades de Superfície , Titânio , Torque
8.
J Prosthodont ; 29(2): 129-135, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29961952

RESUMO

PURPOSE: To investigate the effect of different surface treatments on Vickers hardness and flexural strength of zirconia and lithium disilicate ceramics. MATERIALS AND METHODS: 50 zirconia and 50 lithium disilicate ceramic specimens were used. After identifying one group as the control, grinding, sandblasting, CoJet, and Er:YAG laser were applied on the surface of specimens (n = 10). After applying Vickers hardness test to specimens, flexural strength test was performed. The data were analyzed with two-way ANOVA and Duncan's multiple comparisons tests. RESULTS: There were statistically significant differences found between surface treatment groups in terms of Vickers hardness of zirconia and lithium disilicate ceramics (p < 0.001), but there were no statistically significant differences found between surface treatment groups in terms of flexural strength (p > 0.05). CONCLUSIONS: Surface treatments could affect the hardness of ceramics. Therefore, was zirconia found to be harder and more durable than lithium disilicate ceramics.


Assuntos
Resistência à Flexão , Zircônio , Cerâmica , Porcelana Dentária , Dureza , Teste de Materiais , Propriedades de Superfície
9.
J Dairy Sci ; 103(1): 871-876, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31733876

RESUMO

Stall base and stall surface (i.e., with or without bedding) are key risk factors in cow comfort in dairy herds. In Canada, rubber mats, concrete floors, and mattresses are the most common stall bases used in tie-stall systems. Straw, wood shavings, and sand, at variable depths, are the most commonly used type of bedding. The Clegg hammer (Clegg Impact Soil Tester Hammer; Lafayette Instrument Company, Lafayette, IN) is a tool used by engineers to test the compressibility of pavement or golf course surfaces. Recently, this tool has also been used to measure the compressibility of the stall surface on freestall dairy farms. A total of 32 tie-stall dairy herds were selected in Québec to test the usefulness of the Clegg hammer as a tool to assess stall surface compressibility in tie-stall housing. This study had 2 main objectives: (1) identify the location and the number of measurements needed to obtain a stable indicator of compressibility, and (2) identify differences in the compressibility of the stall surface depending on the stall base and bedding depth. On each farm, we tested the compressibility of 10 stalls. No significant differences were found between the front and the back of the stall for the location of the Clegg hammer measures. The differences in readings of the Clegg hammer were nonsignificant after the third measure taken at the same location, meaning that 3 measures are sufficient at one location to obtain a compressibility measure. Significant differences were found among the different stall base and surface combinations tested. Rubber mats were less compressible than mattresses. When a large quantity of bedding (>7.5 cm) was added on top of rubber mats, the compressibility results were equal to those of mattresses ≥10 yr old without bedding. To appropriately test the compressibility of stall surface in tie-stall farms, we recommend measuring the compressibility of the stall base on its own and with the usual amount of bedding used on the farm. Our study establishes that both stall base and surface affect compressibility, and that a large quantity of bedding helps increase the compressibility of the bed, especially on a harder stall base.


Assuntos
Bovinos/fisiologia , Indústria de Laticínios/instrumentação , Abrigo para Animais , Animais , Roupas de Cama, Mesa e Banho/veterinária , Canadá , Força Compressiva , Indústria de Laticínios/métodos , Feminino , Pisos e Cobertura de Pisos , Dureza , Fatores de Risco
10.
Artigo em Inglês | MEDLINE | ID: mdl-31815983

RESUMO

The purpose of this study was to evaluate the intensity of light-curing units and its relationship with the color stability and microhardness of composite resins with different shades subjected to a thermocycling procedure. Eighty blocks (5.0 × 2.0 mm) of TPH Spectrum composite resin (Dentsply Sirona) were produced and distributed into four groups according to the light-curing units (EC 450, ECEL; Valo, Ultradent) and color of the resin material (A3; C3) (n = 20). Within each group, color stability was measured on half the sample (n = 10) using a UV-2450 visible UV spectrophotometer (Shimadzu), and Knoop hardness was measured on the other half (n = 10) using an HMV 2000 microhardness tester (Shimadzu) before and after thermocycling (12,000 cycles, 5°C and 55°C). Mann-Whitney test was performed on the color stability data; the microhardness data were analyzed using a three-way analysis of variance (ANOVA) and Tukey test (α = .05). The ANOVA results showed that thermocycling, distinct light intensity, and different colors of resin materials influenced the microhardness of the composite resins, which was evidenced by the A3 composite resin light-cured with a Valo polywave showing higher hardness values. There was no statistical difference in the color stability of the A3 composite resin; however, the C3 composite resin light-cured with an EC 450 singlewave light-curing unit showed higher color alteration values. In general, the Valo polywave light-curing unit imparted better mechanical property and color stability to both shades of the composite resins. The different shades of resin material influenced the hardness of the composite resins. Therefore, the light intensity of the light-curing units should be evaluated and monitored, as the amount of light intensity will interfere in the quality and longevity of resin restorations.


Assuntos
Resinas Compostas , Luzes de Cura Dentária , Cor , Dureza , Teste de Materiais
11.
Food Chem ; 308: 124832, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31648093

RESUMO

Potatoes usually suffer from greatly decrease of hardness after boiling, which limits their processing potential in food industry. Moreover, methods for enhancing the hardness of potatoes after boiling are underexplored. In this study, the hardness of potato slices after boiling were increased from 288 g to 2342 g by the combined treatment of lactic acid (LA) and calcium chloride (CC). Through the analysis of the microstructure of the potato cells, the molecular weight distribution and natural sugar ratio of different soluble pectin fractions, and the enzymatic activities (polygalacturonase, PG and pectin methylesterase, PME), the possible mechanism behind the hardness enhancement by LA and CC pretreatment, namely the direct link between pectin and potato structure was revealed. The obtained results confirmed the target spot for enhancing the hardness of potatoes after boiling lay in PG activity and gelation of the pectin, which also could be used to help other plants resist the heat process if pectin existed in their cell wall.


Assuntos
Cloreto de Cálcio/farmacologia , Ácido Láctico/farmacologia , Solanum tuberosum/efeitos dos fármacos , Hidrolases de Éster Carboxílico/metabolismo , Dureza , Temperatura Alta , Pectinas/química , Poligalacturonase/metabolismo , Solanum tuberosum/química , Solanum tuberosum/metabolismo
12.
Meat Sci ; 160: 107968, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31675517

RESUMO

The objective of this study was to evaluate the effect of two different forms of canola oil (pure liquid form or a pre-emulsified form that includes porcine plasma protein hydrolysates modified by oxidized tannic acid) used for pork back-fat substitutions on the physico-chemical characteristics of frankfurters. When compared to the control group, partial replacement of pork back-fat using a pre-emulsified canola oil system exhibited excellent water and fat binding capacities, quicker relaxation times and lower amounts of saturated fatty acids (SFAs) (P < .05), as well as increased hardness, gumminess, and chewiness (P < .05) when verified by dynamic rheology analysis. Additionally, higher replacement ratio of pre-emulsified canola oil did significantly decrease the overall acceptability than the control group (P < .05). Our results indicate that pre-emulsified canola oil provided greater improvement with respect to the physical characteristics of partial pork back-fat replaced frankfurters, when compared to pure canola oil inclusion.


Assuntos
Substitutos da Gordura/química , Produtos da Carne/análise , Óleo de Brassica napus , Animais , Cor , Ácidos Graxos/análise , Dureza , Hidrolisados de Proteína/química , Suínos , Taninos/química
13.
J Food Sci ; 85(1): 65-76, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31869859

RESUMO

The effect of lipids extraction on protein salvation, pasting, and dough rheological behavior of flours dough from hard wheat (HW), extraordinarily soft wheat (Ex-SW), and medium-hard wheat (MHW) flour was analyzed. The varieties selected had wide variation in grain hardness index (17 to 95). Ex-SW revealed lower tryptophan fluorescent emission and water absorption (WA) than MHW and HW varieties. The change in pasting parameters on defatting was the highest for Ex-SW varieties. Native flour (NF) of HW varieties showed high protein content, pasting and dough strength, and fluorescence intensity in comparison to Ex-SW varieties, while on defatting this was reversed. Protein pattern of defatted flour and NF did not differ significantly. Defatting of flours increased WA and decreased dough stability (DS). The decrease in DS on defatting was more for Ex-SW varieties than others. DS for HW and MHW varieties reduced upon defatting. Defatting significantly increased all mixographic and rheological properties except peak time. Overall, results showed that defatting of flour improved paste and dough strength. PRACTICAL APPLICATION: Higher gluten strength of defatted wheat flour of varied grain hardness has wide applications. Most of the Indian bread wheat varieties possess GluD1 high-molecular-weight glutenin subunit (HMW-GS) allelic composition of (2 + 12), which is not suitable for bread making due to weak gluten strength. Defatting of flours improved the gluten strength of strong and weak flour dough of different wheat varieties irrespective of GluD1 allelic composition for HMW-GS. Defatted flour may be used to improve the baking and cooking performance of dough made from weak wheat. These findings are highly suitable for wheat milling and baked product manufacturing industries.


Assuntos
Farinha/análise , Manipulação de Alimentos/métodos , Triticum/química , Pão/análise , Culinária , Glutens/química , Dureza , Reologia , Triticum/classificação
14.
J Sci Food Agric ; 100(1): 268-276, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31512249

RESUMO

BACKGROUND: The application of Pickering emulsion stabilized by food-derived particles is of great interest in the food field, including meat processing. However, the creaming phenomenon is a thorny problem and may impact the resulting product quality. Here, we used polysaccharide nanoparticles from Flammulina velutipes (FVPN) as a stabilizer to prepare a oil/water Pickering emulsion and partly replace the original fat of common emulsified sausage, focusing on exploring the influence of phase separation on the sausage's techno-functional and sensory quality, with the aim of developing a new alternative fat substitute. RESULTS: Reformulated sausages showed increases in moisture (53.24-64.85%) and protein content (11.97-12.76%), but were reduced in fat content (27.28-18.76%). The increased FPOE (FVPN-palm oil emulsion; substitution rate 5-37%) amount in sausages resulted in significantly reduced (P < 0.05) cooking loss (18.87-8.63%). Meanwhile, emulsion improved the springiness and cohesiveness of sausage and significantly reduced (P < 0.05) hardness and chewiness when the replacement amount was less than 20%. Experimental sausages attained a more compact pore structure without harming sensory characteristics. Compared with creaming emulsion, pristine emulsion resulted in a sausage with higher moisture content, lower cooking loss, better elasticity and denser structure. CONCLUSION: The characteristics of sausages could be influenced by emulsion stability. Emulsion, especially with no creaming, can be effectively used as fat substitute at a level of 20% or less without adversely affecting the sensory characteristics of emulsified sausages. The incorporation of FPOE provides the potential for developing a new alternative approach for animal fat improvement in meat products. © 2019 Society of Chemical Industry.


Assuntos
Substitutos da Gordura/análise , Flammulina/química , Aditivos Alimentares/análise , Produtos da Carne/análise , Polissacarídeos/análise , Animais , Culinária , Emulsões/química , Manipulação de Alimentos , Dureza , Humanos , Nanopartículas/química , Óleo de Palmeira/análise , Suínos , Paladar , Água/análise
15.
Arch Oral Biol ; 109: 104573, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31568993

RESUMO

OBJECTIVE: The purpose of this investigation was to establish microstructure, microhardness, fracture toughness, chemical composition, and crack repair of bovine enamel and to compare these features with their human counterparts. DESIGN: Bovine enamel fragments were prepared and optical microscopy and atomic force microscopy were used to establish microstructure; Raman spectroscopy was used to estimate composition and microindentation using Vickers testing was performed to evaluate hardness. RESULTS: A strong dependence between indentation load and microhardness values was observed, as was the case in human enamel. Similar microstructure and chemical composition between bovine and human enamel, 7.89% lower microhardness and 40% higher fracture toughness values for bovine enamel were found. CONCLUSION: From a structural and mechanical standpoint, bovine enamel is a suitable alternative to human enamel for in vitro testing of dental products.


Assuntos
Esmalte Dentário/química , Dureza , Animais , Bovinos , Microscopia de Força Atômica
16.
Carbohydr Polym ; 228: 115373, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31635735

RESUMO

Type of sugar and gelling agents used in confectionery formulations have vital importance since they directly influence physicochemical properties during storage. In this study, the effect of a non-caloric rare sugar, D-allulose (formerly called D-psicose) on the starch based confectionery gels were investigated in the presence and absence of soy protein isolate (SPI) using different experimental techniques for 28 days. For characterization of the formulized gel systems, common techniques were used (SEM, DSC, XRD, moisture content, water activity, hardness and color). Time Domain Nuclear Magnetic Resonance (TD-NMR) technique was also employed to explain dynamics in the systems. Sugar type was found to be a very significant factor affecting gel characteristics and retrogradation. Results showed that D-allulose containing formulations were less prone to retrogradation and showed smaller changes upon storage by supporting presence of better gel network. According to X-ray results, sucrose containing formulations were more susceptible to crystallization. T2 relaxation spectra obtained from NMR experiments showed that number of distinct peaks reduced with the addition of SPI while relaxation times of peaks changed when different type of sugar.


Assuntos
Doces , Armazenamento de Alimentos , Frutose/química , Géis/química , Proteínas de Soja/química , Amido/química , Dureza , Água/química
17.
Food Chem ; 309: 125673, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31784073

RESUMO

New types of precooked pasta products have been developed based on refined and wholegrain wheat and spelt flours. The resulting dry pasta was then assessed for chemical composition, including amino acids composition, phenolics content, as well as antioxidant activity. The precooked pasta quality was also evaluated for starch gelatinization degree, physical properties, hardness, color profile of dry and hydrated pasta, and sensory characteristics. We found that the application of the extrusion-cooking technique for wheat and spelt pasta processing allows to achieve instant products with good nutritional characteristics and high degree of gelatinization, as well as attractive quality and sensory profiles. Microstructure showed compact and dense internal structure with visible bran particles if wholegrain flours were used. Wholegrain wheat and wholegrain spelt precooked pasta were characterized by better nutritional composition and greater antioxidant potential, but lower firmness and increased adhesiveness when compared with refined flours.


Assuntos
Culinária/métodos , Farinha/análise , Triticum/química , Aminoácidos/análise , Antioxidantes/química , Dureza , Fenol/química
18.
Food Chem ; 309: 125704, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31699556

RESUMO

The expeller-pressed (EP) corn germ oil oleogels were prepared using rice bran wax (RBX) at different concentrations (3, 5, 7, and 9 wt%). Their structural properties, including color, hardness, thermal behavior, rheological property, and crystal structure were evaluated. The performance of oleogels for potential food application was examined by incorporating oleogels into cookies as a fully replacement for commercial shortenings. Overall, RBX could form oleogels in both refined and EP corn germ oils at a concentration ≥3 wt%. Refined corn oil produced a stronger gel than crude corn oil. When comparing cookie characteristics, cookies made with both types of oleogels showed similar properties with commercial cookies. This result indicates that oleogels made by refined and EP corn germ oil together with RBX have the potential to imitate the functionality of commercial shortening in the baking industry.


Assuntos
Óleo de Milho/química , Oryza/química , Zea mays/metabolismo , Cor , Manipulação de Alimentos , Dureza , Compostos Orgânicos/química , Oryza/metabolismo , Óleos Vegetais/química , Reologia , Ceras/química
19.
AAPS PharmSciTech ; 21(1): 9, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31797083

RESUMO

Increased human-pet interactions have led to concerns related to the prevention and treatment of ectoparasite infestations. Fipronil (FIP) is a widely used ectoparasiticide in veterinary medicine available for topical administration; however, its use may cause damage to the owners and the environment. The aim of the study was to develop immediate-release tablets of FIP, as well as to determine its pharmacokinetic properties after oral administration in beagle dogs. The prepared FIP tablets were evaluated for pre-compression (angle of repose, speed flow, and Carr's index) and post-compression (weight variation, friability, thickness, hardness, disintegration time, and dissolution rate) parameters. Orally administered FIP at a dose of 2 mg/kg was rapidly absorbed with Cmáx of 3.13 ± 1.39 µg/mL at 1.83 ± 0.40 h post treatment (P.T.) and metabolized with 1.27 ± 1.04 µg/mL at 2.33 ± 0.82 h P.T. for fipronil sulfone (SULF) (the primary metabolite). The elimination of FIP and SULF occurred slowly and had maintained quantifiable plasma levels in the blood for up to 28 days P.T. The goal of the study is aligned with the concept of One Health, which aims to collaboratively achieve the best health for people, animals, and the environment. Therefore, the use of FIP tablets for the control of ectoparasites in dogs may be a safer alternative for owners and the environment.


Assuntos
Antiparasitários/química , Antiparasitários/farmacocinética , Pirazóis/química , Pirazóis/farmacocinética , Administração Oral , Animais , Antiparasitários/administração & dosagem , Cães , Dureza , Pirazóis/administração & dosagem , Comprimidos , Poluição da Água/prevenção & controle
20.
Shanghai Kou Qiang Yi Xue ; 28(4): 378-383, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31792477

RESUMO

PURPOSE: To prepare a soft lining material with high elastic on the basis of excellent characteristics of Eucommia ulmoides gum, and explore its basic physical performance and cytotoxity. METHODS: Basic formula was used based on the existing formula of elastic Eucommia ulmoides gum and medical rubber, then hardness, tensile strength and elongation at break were investigated to determine the final formula of the material, named Eucommia ulmoides gum composite soft denture liner. L929 mouse fibroblasts cultured in vitro were used to detect the toxic effects of 50% of leaching solution released from three kinds of denture soft lining materials by MTT assay. Statistical analysis was performed using SPSS16.0 software package. RESULTS: The kinds and blending proportion of rubber matrix had significant impact on mechanical properties of Eucommia ulmoides gum composite soft denture liner, the addition of Eucommia ulmoides gum significantly increased the hardness, tensile strength and elongation at break of the butadiene rubber. MTT assay showed Eucommia ulmoides gum composite soft denture liner did not have cytotoxicity on L929 mouse fibroblasts. The toxicity levels of 5 groups of Eucommia ulmoides gum composite soft denture liner in the 2nd, 4th, 7th day were maintained in the first stage, only 70:30 group reached the second stage on the 7th day. The cell relative appreciation rate of Silagum and 5 groups of Eucommia ulmoides gum composite soft denture liner in 2nd, 4th, 7th day were significantly higher than that in the self-curing acrylic soft lining material (P<0.05). CONCLUSIONS: Eucommia ulmoides gum and butadiene rubber blend ratio of 70:30, adding appropriate amount of zinc oxide, magnesium, stearic acid, sublimed sulfur, CZ, antioxidants, can get optimum mechanical properties. Eucommia ulmoides gum composite soft denture liner has no effect on L929 fibroblasts proliferation, indicating good biocompatibility.


Assuntos
Reembasadores de Dentadura , Eucommiaceae , Animais , Materiais Dentários , Bases de Dentadura , Dureza , Teste de Materiais , Camundongos , Resistência à Tração
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