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1.
Ciênc. rural (Online) ; 53(10): e20210914, 2023. tab, ilus, graf
Artigo em Inglês | VETINDEX | ID: biblio-1418789

RESUMO

Brewer's spent grain (BSG) is a residue from brewery production, that can be reused as adsorbent of heavy metals like Chromium (Cr). In this study, BSG was used as a biochar for Cr adsorption in batch adsorption experiments. The biochar pyrolysis temperature (500, 600 and 700ºC), pyrolysis time (30, 105 and 180 minutes) and zinc chloride concentration (5, 12.5 and 20%) were evaluated and optimized from a fractional factorial design. An equilibrium adsorption capacity of 78.13 mg.g-1 and a yield of 26.42% were achieved using 700ºC, 30 min, 12.5%. This biochar was applied to the adsorption of Cr in aqueous solution, under different stirring speeds (100, 150 and 200 rpm). The higher agitation speed reduced the adsorption capacity of the coal from 90 to 72 mg.L-1. In addition, the Cr adsorption equilibrium was reached before 100 min. The pseudo-first order model best described the Cr adsorption kinetics. The Redlich-Peterson isothermal model best fitted the experimental data, with the parameter g (close to 1) suggesting Langmuir's assumptions as the most appropriate to describe the adsorption of Cr on the optimized activated carbon.


O bagaço de malte (BM) é um resíduo da produção cervejeira, que pode ser reaproveitado como adsorvente de metais pesados como o Cromo (Cr). Neste estudo, BM foi usado como um biochar para adsorção de Cr em experimentos de adsorção em batelada. O biochar foi avaliado e otimizado a partir de um planejamento fatorial fracionário com as variáveis: temperatura de pirólise (500, 600 e 700ºC), tempo de pirólise (30, 105 e 180 minutos) e concentração de cloreto de zinco (5, 12,5 e 20%). Uma capacidade de adsorção em equilíbrio de 78,13 mg.g-1 e um rendimento de 26,42% foram obtidos usando 700ºC, 30 min, 12,5%. Este biochar foi aplicado na adsorção de Cr em solução aquosa, sob diferentes velocidades de agitação (100, 150 e 200 rpm). Maior velocidade de agitação reduziu a capacidade de adsorção do biochar de 90 para 72 mg.L-1. Além disso, o equilíbrio de adsorção de Cr foi alcançado antes de 100 min. O modelo de pseudo-primeira ordem melhor descreveu a cinética de adsorção de Cr. O modelo isotérmico de Redlich-Peterson foi o que melhor se ajustou aos dados experimentais, com o parâmetro g (próximo de 1) sugerindo as hipóteses de Langmuir como as mais apropriadas para descrever a adsorção de Cr no carvão ativado otimizado.


Assuntos
Indústria Cervejeira , Carvão Vegetal , Cromo , Adsorção
2.
Food Chem ; 391: 133279, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35640341

RESUMO

In view of the low exploitation Garcinia brasiliensis and its richness in bioactive compounds, this article is justified by the need to develop a product which adds value to this fruit. The objective was to develop bacupari pulp powder (BPP) in two stages of maturation and to evaluate its physicochemical, microstructural and bioactive properties. Data showed that BPP can be considered as a source of fiber (≅16 g.100-1/ P < 0.05), a result verified via scanning electron microscopy. The immature pulp can be considered as a source of protein, as it contains>6 g.100-1. Regarding the antioxidant content, it was found that the ABTS method showed the best result (2449 µmolTE/100 g/P > 0.05) and it was the first time that the bioactive compounds folic acid, trans-ferulic acid, and sinapic acid were identified in this fruit. Therefore, the use of the BPP form is an alternative for the consumption of this underexploited fruit.


Assuntos
Garcinia , Antioxidantes/análise , Fibras na Dieta/análise , Frutas/química , Garcinia/química , Pós/análise
3.
J Food Sci ; 85(1): 96-104, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31872872

RESUMO

Juçara fruit pomace is one of the most abundant byproducts of the pulp-making process, generally discarded despite their attractive nutritional content. In this sense, this study aimed to investigate the potential of juçara fruit pomace as an alternative source of starch and natural dyes. Starch extracted from juçara seed (JS) was characterized in approximate composition, crystallinity, thermal profile, morphology, and equilibrium moisture data. Total phenolic content, anthocyanins content, and in vitro antioxidant capacity were assessed for the juçara seedless pomace (JSP). JSP is rich in monomeric anthocyanins (7.19 to 7.23 mg cyanidin 3-O-glycoside/g dry matter [dm]), presents high antioxidant potential, elevated dietary fibers (72.7% dm), considerable amount of lipids (12.8% dm), low protein content, and ash traces. JS is a rich carbon source (76.91% fibers [dm]; 12.21% amylaceous reserve). Being high in carbohydrates, mainly starch, it can be classified as high starch content flour (juçara seed starch-flour [JSS-F]). JSS-F presented B-type crystallinity and conventional starch-like thermal stability. JSS-F exhibited type III sorption isotherm behavior and the Gugghenheim-Anderson-DeBoer model adequately represented the moisture equilibrium data. As a nutritive source of bioactive compounds and starch, juçara pomace should be regarded as a coproduct to be explored as an alternative natural ingredient to food, pharmaceutical, and chemical industries. PRACTICAL APPLICATION: Juçara agroindustrial residues (pomace and seeds) are a promising source of antioxidants and unconventional starch, which are usually discarded after depulping, representing approximately 74% of the fruits. Juçara pomace can be used to produce flour with marketing potential due to their functional properties and nutritional value. This flour can be incorporated directly into formulations or be used in extraction processes to obtain components of interest, for example, anthocyanins, to be used as a natural food dye. Starch can be extracted from juçara seeds, presenting adequate technological properties for partial replacement of conventional starches.


Assuntos
Euterpe/química , Extratos Vegetais/análise , Amido/análise , Antocianinas/análise , Antocianinas/isolamento & purificação , Antioxidantes/análise , Antioxidantes/isolamento & purificação , Fibras na Dieta/análise , Farinha/análise , Frutas/química , Glicosídeos/análise , Glicosídeos/isolamento & purificação , Valor Nutritivo , Fenóis/análise , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Sementes/química , Amido/isolamento & purificação , Resíduos/análise
4.
Braz. arch. biol. technol ; 63: e20190743, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1132233

RESUMO

Abstract Monofloral honeys are high-added-value food, a reason for constant cases of fraud. This study investigated Brazilian monofloral honeys from Hovenia dulcis flowering produced by Apis mellifera and Tetragonisca angustula bees. Chemical, physicochemical, rheological, and melissopalynological analysis were assessed. Properties such as moisture, pH, ashes, total acidity, total available carbohydrate, and soluble sugars of all analyzed honey samples agreed with the established by the legislation. All the honey samples were satisfactorily fitted by both Ostwald-de Waele and Casson rheological models revealing homogenous products, mostly presenting pseudoplastic character. The melissopalynology confirmed the presence of H. dulcis pollen in the MH samples; however, some honeys did not show >45% pollen of H. dulcis, thus revealing mislabeling cases. Continuous evaluation of honey is necessary, once this is a valuable food frequently involved in frauds, hence causing problems to consumers.


Assuntos
Mel/análise , Reologia , Abelhas , Fenômenos Químicos
5.
Food Res Int ; 123: 1-10, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31284956

RESUMO

Multivariate data analysis feasibility for the evaluation of Brazilian stingless bee honey (SBH) by pollen spectrum, bioactive compounds content, physicochemical, antioxidant and antimicrobial analysis was investigated. Levels of total and individual phenolics content were analyzed by HPLC-PDA. The antioxidant capacity was performed by 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH), oxygen radical absorption capacity (ORAC) and ferric reducing antioxidant power (FRAP) assays. The total phenolic compounds from the thirty-two SBH was positively correlated with the antioxidant capacity. Bioactive compounds such as p-coumaric acid, quercetin, and hesperetin were identified in all the samples. Brazilian SBH shows more effective antibacterial activity against Gram-negative bacteria (E. coli and S. Typhimurium) compared to Gram-positive ones. Results also revealed that SBH could reach up to 45% higher antioxidant and biological activities than the traditional Apis mellifera honey. Chemometrics shows that chemical and biological properties of SBH have a strong relationship with the pollen botanical origin. Principal component analysis (PCA) grouped the honey into three categories with predominant pollen from Verbenaceae, Asteraceae and Sapindaceae families, confirming that SBH belonging to the same floral origin present similar characteristics.


Assuntos
Abelhas/classificação , Mel/análise , Pólen/química , Animais , Antibacterianos/análise , Antibacterianos/farmacologia , Antioxidantes/análise , Abelhas/metabolismo , Compostos de Bifenilo/análise , Brasil , Fenômenos Químicos , Cromatografia Líquida de Alta Pressão , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Radicais Livres/análise , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/metabolismo , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/metabolismo , Indicadores e Reagentes/análise , Análise Multivariada , Fenóis/análise , Picratos/análise , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/metabolismo
6.
Saudi J Biol Sci ; 26(4): 633-646, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31048986

RESUMO

Pleurotus genus is one of most extensively studied white-rot fungi due to its exceptional ligninolytic properties. It is an edible mushroom and it also has several biological effects, as it contains important bioactive molecules. In basidiomycete fungi, lignocellulolytic enzymes are affected by many typical fermentation factors, such as medium composition, ratio of carbon to nitrogen, pH, temperature, air composition, etc. The survival and multiplication of mushrooms is related to a number of factors, which may act separately or have interactive effects among them. Out that understanding challenges in handling Pleurotus species mushroom requires a fundamental understanding of their physical, chemical, biological and enzymatic properties. This review presents a practical checklist of available intrinsic and extrinsic factors, providing useful synthetic information that may help different users. An in-depth understanding of the technical features is needed for an appropriate and efficient production of Pleurotus spp.

7.
Ci. Rural ; 48(6): e20170732, June 28, 2018. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-738911

RESUMO

Brazilian pine seeds (pinhão) are gluten-free seeds produced by the native pine species named Araucaria angustifolia. In this study, gluten-free cake mixes composed of Brazilian pine seed flour and rice flour were developed. The cake mixes were produced following a Simplex Centroid experimental design, with rice flour and Brazilian pine seed flour contents ranging from 50 to 100% and from 0 to 50%, respectively. Mixes were analyzed for chemical composition, apparent paste viscosity, and particle size distribution. The resulting cakes were analyzed for sensory acceptance, texture, specific volume and chemical composition. The Brazilian pine seed flour showed a peak viscosity on heating of 1.761Pa.s against 4.747Pa.s for the 100% rice flour sample. The variation of firmness of cakes decreased with increasing percentage of Brazilian pine seed flour. Cakes containing Brazilian pine seed flour at 25-37.5% of the formulation presented highest overall acceptance.(AU)


O pinhão trata-se de uma semente sem glúten, produzida pelo pinheiro da espécie Araucaria angustifolia. Neste estudo, foram desenvolvidas misturas de bolo sem glúten, compostas por farinha de pinhão e farinha de arroz. As misturas de bolo foram produzidas conforme o modelo experimental Simplex Centroid, que definiu as proporções entre a farinha de arroz e a farinha de pinhão na variação de 50 a 100% e 0 a 50%, respectivamente. As misturas foram analisadas quanto à composição química, viscosidade aparente da pasta e distribuição de tamanho de partícula. Os bolos resultantes foram submetidos às análises de aceitação sensorial, textura volume específico e composição química. A farinha de pinhão demostrou ocorrência do pico de viscosidade ao aquecimento no valor de 1,761Pa.s contra 4,747Pa.s da amostra composta por 100% de farinha de arroz. A variação da firmeza dos bolos diminuiu com o aumento da porcentagem de farinha de pinhão. Em termos sensoriais, os bolos contendo entre 25 a 37,5% de farinha de pinhão apresentaram maior aceitação geral.(AU)


Assuntos
Reologia , Fibras na Dieta , Indústria de Farinhas , Sensação , Dieta Livre de Glúten , Indústria Alimentícia
8.
Food Res Int ; 109: 572-582, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29803485

RESUMO

The aim of this work was to investigate the physicochemical, thermal, and functional properties of partially defatted sapucaia nut (Lecythis pisonis Cambess.) flours (PDSF) degreased by subcritical propane (20-60 °C; 20-100 bar) and supercritical CO2 + ethanol (1:1 w/w) as co-solvent (60 °C; 200 bar) in comparison to the PDSF obtained through Soxhlet extraction with petroleum ether. Under the conditions studied herein, compressed propane has a minor effect on the granules' morphology (average particle size between 22 and 32 µm) or in the physicochemical characteristics of the PDSF. It caused a minimum impact on the nutritional profile of the samples; unlike, the thermogravimetric analysis revealed that there is an influence on the thermal stability of the PDSF. Functional characteristics, such as emulsifying (8-20 m2/g), foam (6-12%), and high water (0.35-1.38 g/g flour) and oil (0.72-1.57 g/g flour) absorption capacity, were observed in PDSF. Defatted flours were found to be effective in the production of emulsions with structures that showed micrometric-sized droplets (up to 85% droplet size <15.0 µm) with alleged stability. PDSF is a source of proteins (31-49%) and carbohydrates (17-31%), thus it can be used as an ingredient to produce foodstuff in bakery and confectionery aiming to increase their nutritional value and functional properties.


Assuntos
Ingredientes de Alimentos/análise , Lecythidaceae/química , Nozes/química , Cromatografia com Fluido Supercrítico , Cor , Carboidratos da Dieta/análise , Emulsões , Análise de Alimentos/métodos , Manipulação de Alimentos/métodos , Valor Nutritivo , Tamanho da Partícula , Proteínas de Vegetais Comestíveis/análise , Solventes/química , Termogravimetria , Água/química
9.
Ciênc. rural (Online) ; 48(6): e20170732, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1045139

RESUMO

ABSTRACT: Brazilian pine seeds (pinhão) are gluten-free seeds produced by the native pine species named Araucaria angustifolia. In this study, gluten-free cake mixes composed of Brazilian pine seed flour and rice flour were developed. The cake mixes were produced following a Simplex Centroid experimental design, with rice flour and Brazilian pine seed flour contents ranging from 50 to 100% and from 0 to 50%, respectively. Mixes were analyzed for chemical composition, apparent paste viscosity, and particle size distribution. The resulting cakes were analyzed for sensory acceptance, texture, specific volume and chemical composition. The Brazilian pine seed flour showed a peak viscosity on heating of 1.761Pa.s against 4.747Pa.s for the 100% rice flour sample. The variation of firmness of cakes decreased with increasing percentage of Brazilian pine seed flour. Cakes containing Brazilian pine seed flour at 25-37.5% of the formulation presented highest overall acceptance.


RESUMO: O pinhão trata-se de uma semente sem glúten, produzida pelo pinheiro da espécie Araucaria angustifolia. Neste estudo, foram desenvolvidas misturas de bolo sem glúten, compostas por farinha de pinhão e farinha de arroz. As misturas de bolo foram produzidas conforme o modelo experimental Simplex Centroid, que definiu as proporções entre a farinha de arroz e a farinha de pinhão na variação de 50 a 100% e 0 a 50%, respectivamente. As misturas foram analisadas quanto à composição química, viscosidade aparente da pasta e distribuição de tamanho de partícula. Os bolos resultantes foram submetidos às análises de aceitação sensorial, textura volume específico e composição química. A farinha de pinhão demostrou ocorrência do pico de viscosidade ao aquecimento no valor de 1,761Pa.s contra 4,747Pa.s da amostra composta por 100% de farinha de arroz. A variação da firmeza dos bolos diminuiu com o aumento da porcentagem de farinha de pinhão. Em termos sensoriais, os bolos contendo entre 25 a 37,5% de farinha de pinhão apresentaram maior aceitação geral.

10.
Braz. arch. biol. technol ; 56(3): 467-474, May-June 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-679194

RESUMO

The aim of this work was to develop linear models using the image analysis coupled with density measurements to monitor the dilution of the Physalis juice in the concentrations ranging from 0 to 100% in mass of juice pulp. A sample corresponding to 20% in the mass of juice pulp was for validating purposes and a prediction of 19.9±0.3%. The models with three parameters showed the best predictions, providing this technique with a promising future for the monitoring the dilution of fruit juices.

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