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1.
Int J Biol Macromol ; 163: 1421-1432, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32738324

RESUMO

This work aims to encapsulate anthocyanins and phenolic compounds extracted from a native Brazilian fruit peel - jabuticaba (Plinia cauliflora (Mart.) Kausel) and propolis from Tubuna (Scaptotrigona bipunctata) stingless bees, with great potential benefits for human health. The alginate encapsulation was conducted by the ionotropic gelation through the dripping into the CaCl2 solution. Both raw extracts were characterized by TPC - total phenolic content (Folin-Ciocalteu), AA -antioxidant activity (DPPH and ABTS assays), and TMAC - total monomeric anthocyanin concentration (pH differential method); as well as their resultant mixture (2:1 jabuticaba/propolis). The obtained beads presented highly efficient encapsulation of total polyphenols (~98%) and monomeric anthocyanins (~89%), with spherical morphology and smooth surface obtaining a mean diameter between 200 and 250 µm. In vitro release study showed that JPE/alginate beads were completely disintegrated at pH 7.4 (intestinal pH), but they were resistant to gastric pH (1.2) presenting a slow release of about 40% in 240 min. This is the first report that encapsulates the mixture of jabuticaba and propolis extracts and may contribute to the utilization of a great source of bioactive compounds besides the potential pigment of anthocyanins, an alternative to natural and healthy food/beverage colorants.


Assuntos
Alginatos/química , Antioxidantes/química , Myrtaceae/química , Extratos Vegetais/química , Própole/química , Animais , Antocianinas/química , Artrópodes/química , Abelhas/química , Brasil , Frutas/química , Fenóis/química , Polifenóis/química
2.
Int J Biol Macromol ; 137: 992-1001, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31279883

RESUMO

For the first time, TiO2 immobilized in alginate polymer was modified to turn it into a buoyant photocatalyst for achieving both higher radiance utilization efficiency and easier post-treatment separation. In this work, the low-density TiO2 alginate-based photocatalyst was synthesized by ionotropic gelation using a gas-forming agent (CaCO3, NaHCO3) in an acid medium (CH3COOH). The TiO2, CaCO3, and CH3COOH concentrations affect buoyancy, and the best response (100% of floating beads) after 24 h was determined using a central composite rotatable design combined with the response surface methodology. It was found that the optimal TiO2/CaAlg formulation were the following concentrations: 1.1 wt% TiO2, 2.3 wt% CaCO3, and 6.4 vt% CH3COOH. The resulting floating beads were uniform (size: 3.4 ±â€¯0.4 mm, density: 0.9215 g/cm3), with a rough surface and porous internal structure, as observed in the characterizations using SEM/EDX, TGA, XRD, and FT-IR. The photocatalytic activity under UV irradiation (125 W, 254 nm) was evaluated for tartrazine dye removal, achieving up to 89% discoloration upon the first use with TOC removal capacity even after seven use cycles. This easily recoverable floating photocatalyst may be applied to improve the photocatalytic treatment of industrial wastewater, making most efficient use of photoactivation with no mechanical stirring.


Assuntos
Alginatos/química , Processos Fotoquímicos , Titânio/química , Catálise , Tartrazina/química , Tartrazina/isolamento & purificação , Raios Ultravioleta , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
3.
J Food Sci ; 80(6): C1170-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25920613

RESUMO

The amino acid profile in dessert apple must and its effect on the synthesis of fusel alcohols and esters in cider were established by instrumental analysis. The amino acid profile was performed in nine apple musts. Two apple musts with high (>150 mg/L) and low (<75 mg/L) nitrogen content, and four enological yeast strains, were used in cider fermentation. The aspartic acid, asparagine and glutamic acid amino acids were the majority in all the apple juices, representing 57.10% to 81.95%. These three amino acids provided a high consumption (>90%) during fermentation in all the ciders. Principal component analysis (PCA) explained 81.42% of data variability and the separation of three groups for the analyzed samples was verified. The ciders manufactured with low nitrogen content showed sluggish fermentation and around 50% less content of volatile compounds (independent of the yeast strain used), which were mainly 3-methyl-1-butanol (isoamyl alcohol) and esters. However, in the presence of amino acids (asparagine, aspartic acid, glutamic acid and alanine) there was a greater differentiation between the yeasts in the production of fusel alcohols and ethyl esters. High contents of these aminoacids in dessert apple musts are essential for the production of fusel alcohols and most of esters by aromatic yeasts during cider fermentation.


Assuntos
Bebidas Alcoólicas/análise , Aminoácidos/metabolismo , Fermentação , Frutas/química , Malus/química , Saccharomyces cerevisiae/metabolismo , Compostos Orgânicos Voláteis/análise , Álcoois/metabolismo , Ésteres/metabolismo , Humanos , Nitrogênio/metabolismo , Pentanóis/metabolismo
4.
Ciênc. rural ; 44(4): 717-722, Apr. 2014. ilus, tab
Artigo em Português | LILACS-Express | LILACS | ID: lil-705310

RESUMO

O objetivo deste trabalho foi avaliar o efeito de dois pré-tratamentos (pt) na desidratação osmo-convectiva: Pré-tratamento químico a 20°C por 5min em solução de ácido cítrico, bissulfito de sódio e carbonato de cálcio a 0,1% cada (pt-ABC) e por branqueamento a 80°C por 5min (pt-B), bem como a combinação pt-ABC seguido de pt-B (amostra:solução = 1:10 w/w). O pt-ABC provocou aumento de massa (13% em média) entretanto o pt-B perda (-34% em média). A desidratação osmótica a 20°C por 60min em solução de NaCl a 10% reduziu a massa de fatias não pré-tratadas em 43%. Esse nível de redução de massa não pode ser atingido com o uso do pt-ABC, mas melhorou para 49% para fatias submetidas ao pt-B. Os pré-tratamentos reduziram o tempo de secagem (70°C e com circulação de ar de 18m³ h-1) de 150min para 60min para atingir o nível de atividade de água do produto seco igual ou menor a do produto comercial. As fatias submetidas ao pt-ABC ou do controle apresentaram boa capacidade de reidratação. As fatias que foram submetidas aos dois pré-tratamentos apresentaram coloração mais clara e menos enrugadas após secagem, aparência similar foi observada às do pt-ABC. O pt-ABC pode ser usado para se obter fatias de champignon seco com aspecto visual e capacidade de reidratação adequados para o desenvolvimento de novos produtos para consumo direto ou que necessite reidratação.


The objective of this paper was assessments the effect of pre-treatment (pt) in osmo-convective dehydration: Chemical pretreatment at 20°C for 5min with 0.1% solution of citric acid, sodium bisulfite and calcium carbonate (pt-ABC) and bleaching at 80°C for 5min (pt-B), as well the combination pt-ABC followed by pt-B (sample:solution = 1:10 w/w). The pt-ABC provoked mass increase (13% on average), while pt-B caused loss (-34% on average). Osmotic dehydration at 20°C for 60 min with 10% NaCl reduced mass of slices not pretreated at 43%. This level of mass reduction was not achieved for the pt-ABC, but it was improved for 49% to slices subjected to pt-B. Pretreatments reduced drying time (70°C and air circulation 18m³ h-1) from 150min to 60min to achieve the desired a w. Water activity of dried product was equal to or less than the commercial product. Slices subjected to pt-ABC or from control group had good rehydration capacity. Slices subjected to combined pt and dried showed lighter color and were less wrinkled. pt-ABC allowed very similar results. The pt-ABC must be used to obtain slices of dry champignon with visual aspect and rehydration capacity suitable for the development of new products for direct consumption or require rehydration.

5.
Braz. arch. biol. technol ; 54(1): 197-206, Jan.-Feb. 2011. ilus, graf, tab
Artigo em Inglês | LILACS-Express | LILACS | ID: lil-576775

RESUMO

An industrial system for the production of white liquor of a pulp and paper industry, Klabin Paraná Papéis, formed by ten reactors was modeled, simulated, and analyzed. The developed model considered possible water losses by the evaporation and reaction, in addition to variations in the volumetric flow of lime mud across the reactors due to the composition variations. The model predictions agreed well with the process measurements at the plant and the results showed that the slaking reaction was nearly complete at the third causticizing reactor, while causticizing ends by the seventh reactor. Water loss due to slaking reaction and evaporation occurred more pronouncedly in the slaker reactor than in the final causticizing reactors; nevertheless, the lime mud flow remained nearly constant across the reactors.

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