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1.
Artigo em Inglês | MEDLINE | ID: mdl-30255763

RESUMO

BACKGROUND: The growing interest on supercritical fluids applied to particle engineering over the last years has received attention from the food and non-food industries, in terms of processing, packaging and preservation of these products. The rapid expansion of supercritical solutions (RESS) process is an efficient and promising method to produce small particles with narrow size distribution. OBJECTIVE: In this review we report technological aspects on the application of RESS process applied to the food and non-food industry, considering recent data and patent survey registered in literature. METHODS: The effect of process parameters solvent, temperature, pressure, nozzle size among others, during RESS on the size, structure and morphology of the resulted particles, and the main differences about recent patented RESS processes are reviewed. RESULTS: Most of experimental works intend to optimize their processes through investigation of process parameters. CONCLUSIONS: RESS is an efficient and ecological alternative for the production of particles with high yield of bioactive constituents of interest to food industry. On the other hand, patents developed using this type of process to food products are very scarce, less attention being given be given to the potential of this technique to develop particles from plant extracts with bioactive substances.

2.
Artigo em Inglês | MEDLINE | ID: mdl-30039768

RESUMO

BACKGROUND: The use of nutritional supplementation of the brewer's wort can be an interesting option to increase cell viability and yeast fermentability. OBJECTIVE: This study aims at to evaluate the effects of the variables wort concentration and nutritional supplementation with palm oil in the production of beer in high density wort. METHOD: The process effects were evaluated through the central composite rotational design of type 22 associated with the response surface methodology (RSM). The fermentations were carried out using the commercial Saccharomyces cerevisiae yeast, lager type, at 15 °C. RESULTS: The mathematic models and RSM obtained were an efficiency strategy to determine the optimum fermentation point for the ethanol volumetric productivity (wort concentration of 20.90 °P and palm oil content of 0.19 % v/v) and for the apparent degree of fermentation (wort concentration of 16.90 °P and palm oil content of 0.22% v/v). There was a good correlation between the experimental values observed and predicted by the model, indicating that the fit of the model was satisfactory and it can be inferred that the increase of the wort concentration and the nutritional supplementation with the palm oil reached an ethanol volumetric productivity of 0.55 g/L.h and an apparent degree of fermentation of 50.20 %. CONCLUSION: Therefore, it can be concluded that our study demonstrates that nutritional supplementation with palm oil is an alternative and promising option for the breweries to increase productivity. There are recent patents also suggesting the advantages of using alternative nutritional supplements in beverage production.

3.
Food Sci. Technol (SBCTA, Impr.) ; 38(1): 13-18, Jan.-Mar. 2018. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-892236

RESUMO

Abstract In the present study, the software Aspen Plus® was used to analyse two different systems for CO2 recycle in a SFE process for extraction of more polar compounds using ethanol as co-solvent, the most common co-solvent used due to its environment-friendly nature. The extraction process of β-ecdysone from Brazilian ginseng roots was considered as example in the computational simulations. The first CO2 recycle system, named Recycle A, considered the compression of the CO2 separated in the second flash to the recycle pressure assumed at the first flash tank, its cooling to 25 °C and recirculation, while the second recycle system, named Recycle B, considered the cooling and pumping of the CO2 separated in the second flash, its heating to 25 °C and recirculation. The best techno-economic condition to operate the recycling step would be using Recycle A at 40 bar and 30 °C considering a stand-alone SFE process; and using Recycle B at 40 bar and 40 °C, considering this process in close proximity of a hypothetical sugarcane biorefinery. Therefore, these results suggest that the selection where would be located the SFE plant should be taken into account during the first steps of the process design.

4.
Materials (Basel) ; 9(6)2016 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-28773616

RESUMO

Recently, supercritical fluid extraction (SFE) has been indicated to be utilized as part of a biorefinery, rather than as a stand-alone technology, since besides extracting added value compounds selectively it has been shown to have a positive effect on the downstream processing of biomass. To this extent, this work evaluates economically the encouraging experimental results regarding the use of SFE during annatto seeds valorization. Additionally, other features were discussed such as the benefits of enhancing the bioactive compounds concentration through physical processes and of integrating the proposed annatto seeds biorefinery to a hypothetical sugarcane biorefinery, which produces its essential inputs, e.g., CO2, ethanol, heat and electricity. For this, first, different configurations were modeled and simulated using the commercial simulator Aspen Plus® to determine the mass and energy balances. Next, each configuration was economically assessed using MATLAB. SFE proved to be decisive to the economic feasibility of the proposed annatto seeds-sugarcane biorefinery concept. SFE pretreatment associated with sequential fine particles separation process enabled higher bixin-rich extract production using low-pressure solvent extraction method employing ethanol, meanwhile tocotrienols-rich extract is obtained as a first product. Nevertheless, the economic evaluation showed that increasing tocotrienols-rich extract production has a more pronounced positive impact on the economic viability of the concept.

5.
Crit Rev Biotechnol ; 35(3): 302-12, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24494703

RESUMO

There is increased interest in reducing our reliance on fossil fuels and increasing the share of renewable raw materials in our energy supply chain due to environmental and economic concerns. Ethanol is emerging as a potential alternative to liquid fuels due to its eco-friendly characteristics and relatively low production costs. As ethanol is currently produced from commodities also used for human and animal consumption, there is an urgent need of identifying renewable raw materials that do not pose a competitive problem. Lignocellulosic agricultural residues are an ideal choice since they can be effectively hydrolyzed to fermentable sugars and integrated in the context of a biorefinery without competing with the food supply chain. However, the conventional hydrolysis methods still have major issues that need to be addressed. These issues are related to the processing rate and generation of fermentation inhibitors, which can compromise the quality of the product and the cost of the process. As the knowledge of the processes taking place during hydrolysis of agricultural residues is increasing, new techniques are being exploited to overcome these drawbacks. This review gives an overview of the state-of-the-art of hydrolysis with subcritical and supercritical water in the context of reusing agricultural residues for the production of suitable substrates to be processed during the fermentative production of bioethanol. Presently, subcritical and/or supercritical water hydrolysis has been found to yield low sugar contents mainly due to concurrent competing degradation of sugars during the hydrothermal processes. In this line of thinking, the present review also revisits the recent applications and advances to provide an insight of future research trends to optimize on the subcritical and supercritical process kinetics.


Assuntos
Agricultura , Biocombustíveis , Biomassa , Biotecnologia/métodos , Etanol , Hidrólise
6.
Pharmacogn Rev ; 8(16): 88-95, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25125880

RESUMO

Extraction processes are largely used in many chemical, biotechnological and pharmaceutical industries for recovery of bioactive compounds from medicinal plants. To replace the conventional extraction techniques, new techniques as high-pressure extraction processes that use environment friendly solvents have been developed. However, these techniques, sometimes, are associated with low extraction rate. The ultrasound can be effectively used to improve the extraction rate by the increasing the mass transfer and possible rupture of cell wall due the formation of microcavities leading to higher product yields with reduced processing time and solvent consumption. This review presents a brief survey about the mechanism and aspects that affecting the ultrasound assisted extraction focusing on the use of ultrasound irradiation for high-pressure extraction processes intensification.

7.
Water Sci Technol ; 60(4): 1081-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19700848

RESUMO

This study provides a preliminary contribution to the development of an industrial process for the UV/TiO(2) water treatment by introducing a novel support for TiO(2) immobilization. For the following study, Methylene Blue (MB) was chosen as the model dye to evaluate this novel immobilization system. The results showed that TiO(2) immobilized in a Ca-alginate bead retained its photoactivity during all of the experiments and the TiO(2)-gel beads presented good stability in water for maintaining its shape after several uses. When a proportion of 10% (v/v) of these beads was used, the configuration system demonstrated an improved mass transfer and consequently enhanced degradation efficiency. Experiments were also performed using 'recycled' beads. The results showed an increase in the degradation efficiency when the beads were reused, with an eventual 'self-destructive' effect. These studies showed great promise regarding the recyclable reagents with a reduction in waste at no greater cost or reduction in efficiency. Therefore, the potential of TiO(2)-gel beads as a simple and environmentally friendly catalyst for continuous use was developed.


Assuntos
Alginatos/química , Cálcio/química , Azul de Metileno/química , Titânio/química , Adsorção/efeitos da radiação , Catálise/efeitos da radiação , Cor , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Luz , Microscopia Eletrônica de Varredura , Microesferas , Espectrofotometria Ultravioleta , Fatores de Tempo
8.
Appl Biochem Biotechnol ; 141(2-3): 215-27, 2007 May-Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18025553

RESUMO

Sugarcane bagasse pretreated by three different procedures (with 2% [v/v] polyethyleneimine (PEI), with 2% [w/v] NaOH, or with a sequence of NaOH and PEI) was used as cell immobilization carrier for xylitol production by Candida guilliermondii yeast. Fermentations using these pretreated carriers were performed in semidefined medium and in a hydrolysate medium produced from sugarcane bagasse hemicellulose. Sugarcane bagasse pretreated with NaOH was the best carrier obtained with respect to immobilization efficiency, because it was able to immobilize a major quantity of cells (0.30 g of cells/g of bagasse). Fermentation in semidefined medium using the NaOH-pretreated carrier attained a high efficiency of xylose-to-xylitol bioconversion (96% of the theoretical value). From hydrolysate medium, the bioconversion efficiency was lower (63%), probably owing to the presence of other substances in the medium that caused an inadequate mass transfer to the cells. In this fermentation medium, better results with relation to xylitol production were obtained by using PEI-pretreated carrier (xylose-to-xylitol bioconversion of 81% of the theoretical and volumetric productivity of 0.43 g/[L.h]). The results showed that sugarcane bagasse is a low-cost material with great potential for use as cell immobilization carrier in the fermentative process for xylitol production.


Assuntos
Candida/metabolismo , Celulose/metabolismo , Saccharum/metabolismo , Xilitol/química , Biomassa , Biotecnologia/métodos , Células Imobilizadas , Celulose/química , Meios de Cultura/metabolismo , Fermentação , Cinética , Microscopia Eletrônica de Varredura , Polissacarídeos/química
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