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1.
Molecules ; 25(17)2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32867210

RESUMO

The effects of supercritical CO2 processing on the chemical stability of fructooligosaccharides (FOS) and other functional and nutritional compounds were evaluated employing non-thermal and thermal approaches. Apple juice was enriched with Pfaffia glomerata roots aqueous extract due to its high content of short-chain FOS and then subjected to different levels of temperature (40 and 60 °C), pressure (8 and 21 MPa), and CO2 volume ratio (20 and 50%). The percentage of CO2 volume was evaluated concerning the total volume of the high-pressure reactor. Also, the functional beverage was thermally treated at 105 °C for 10 min. Physicochemical properties (pH and soluble solid content), beta-ecdysone, sugars (glucose, fructose, and sucrose), and FOS (1-kestose, nystose, and fructofuranosylnystose) content were determined. The pH and soluble solid content did not modify after all treatments. The pressure and CO2 volume ratio did not influence the FOS content and their chemical profile, however, the temperature increase from 40 to 60 °C increased the nystose and fructofuranosylnystose content. High-temperature thermal processing favored the hydrolysis of 1-kestose and reduced the sucrose content. Regarding beta-ecdysone, its content remained constant after all stabilization treatments demonstrating thus its high chemical stability. Our results demonstrated that supercritical CO2 technology is a promising technique for the stabilization of FOS-rich beverages since the molecular structures of these fructans were preserved, thus maintaining their prebiotic functionality.


Assuntos
Amaranthaceae/química , Dióxido de Carbono/química , Sucos de Frutas e Vegetais , Alimento Funcional , Oligossacarídeos/química , Pasteurização , Extratos Vegetais/química , Malus/química , Raízes de Plantas/química
2.
Molecules ; 25(24)2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33371297

RESUMO

Haematococcus pluvialis is the largest producer of natural astaxanthin in the world. Astaxanthin is a bioactive compound used in food, feed, nutraceutics, and cosmetics. In this study, astaxanthin extraction from H. pluvialis by supercritical fluid extraction was evaluated. The effects of temperature (40 and 50 °C), pressure (40 and 50 MPa), and CO2 flow rate (2 and 4 L/min) were investigated. The results showed that the highest astaxanthin recovery was obtained at 50 °C/50 MPa and the CO2 flow rates evaluated had no significant effect. It was possible to achieve astaxanthin recoveries of 95% after 175 min for a CO2 flow rate of 2 L/min, and 95 min for CO2 flow rate of 4 L/min. The ω-6/ω-3 ratios obtained were similar in all conditions, reaching 0.87, demonstrating that the extracts from H. pluvialis by SFE are rich in unsaturated fatty acids (UFA) which increases their positive effects when used as a functional ingredient in food.


Assuntos
Dióxido de Carbono/química , Clorofíceas/química , Cromatografia com Fluido Supercrítico/métodos , Ácidos Graxos/química , Microalgas/química , Tecnologia/métodos , Xantofilas/química
3.
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
4.
Bioprocess Biosyst Eng ; 35(7): 1229-37, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22388740

RESUMO

This work is focused on the characterization of a commercial cellulase in terms of optimum pH and temperature, stability to pH and temperature and affinity of this enzyme to several substrates, determining the Michaelis-Menten parameters. Maximum activity of cellulase was obtained for the temperature range from 40 to 50 °C and pH from 5.2 to 5.5. Enzyme activity decreased only 15% after 150 h of reaction at temperatures between 30 and 50 °C. No loss of activity was observed at pH 5.0 and 5.5. The cellulase showed satisfactory results in the hydrolysis of agroindustrial substrates, since similar activity was verified on filter paper and other agroindustrial substrates.


Assuntos
Agricultura , Celulase/metabolismo , Celulase/antagonistas & inibidores , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Hidrólise , Temperatura
5.
Food Chem ; 341(Pt 2): 128155, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33045587

RESUMO

This study investigated the impact of adding ß-carotene on the structure of fresh O/W emulsions with different oil phase (sunflower oil-LCT or NEOBEE®1053-MCT) and emulsifiers (WPI, Tween 80 - T80 or WPI/T80 mixture). In this sense, the behavior of emulsions through the gastrointestinal tract, the stability and bioaccessibility of ß-carotene were also assessed. The ß-carotene reduced the interfacial tension of the LCT/MCT-water systems. The addition of ß-carotene promoted an increase of viscoelasticity of LCT/MCT-T80 (0.5%WPI/0.5%T80 and 1%T80 w/w) interfaces, but an increase of WPI content reduced the viscoelasticity of interfacial layers (LCT/MCT-1% WPI). These changes in the interface properties influenced the mean droplet size and ζ-potential of the fresh emulsions. LCT systems presented similar bioaccessibility/stability of ß-carotene. However, ß-carotene entrapped within protein-coated MCT droplets was more stable than within T80-MCT systems. Our results show that ß-carotene interacted with other ingredients of emulsions changing their properties and behavior under gastrointestinal tract as well as the stability/bioaccessibility of ß-carotene.


Assuntos
Emulsões/química , Polissorbatos/química , beta Caroteno/química , Disponibilidade Biológica , Digestão , Emulsificantes/química , Óleo de Girassol , Tensão Superficial , Viscosidade , Água/química , Proteínas do Soro do Leite/química , beta Caroteno/farmacocinética
6.
Ultrason Sonochem ; 66: 105068, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32224449

RESUMO

This study presents the production of a novel natural blue colorant obtained from the cross-linking between milk proteins and genipin assisted by low-frequency and high-power ultrasound technology. Genipin was extracted from unripe Genipa americana L. using milk as a solvent. Also, milk colloidal system was used as a reaction medium and carrier for the blue color compounds. The effects of ultrasound nominal power (100, 200, 300, and 400 W) on the blue color formation kinetics in milk samples were evaluated at 2, 24, and 48 h of cold storage in relation to their free-genipin content and color parameters. In addition, Fourier transform infrared (FTIR) spectrum, droplet size distribution, microstructure, and kinetic stability of the blue colorant-loaded milk samples were assessed. Our results have demonstrated that the ultrasound technology was a promising and efficient technique to obtain blue colorant-loaded milk samples. One-step acoustic cavitation assisted the genipin extraction and its diffusion into the milk colloidal system favoring its cross-linking with milk proteins. Ultrasound process intensification by increasing the nominal power promoted higher genipin recovery resulting in bluer milk samples. However, the application of high temperatures associated with intensified acoustic cavitation processing favored the occurrence of non-enzymatic browning due to the formation of complex melanin substances from the Maillard reaction. Also, the blue milk samples were chemically stable since their functional groups were not modified after ultrasound processing. Likewise, all blue colorant-loaded milk samples were kinetically stable during their cold storage. Therefore, a novel natural blue colorant with high-potential application in food products like ice creams, dairy beverages, bakery products, and candies was produced.


Assuntos
Produtos Biológicos/química , Corantes/química , Leite/química , Rubiaceae/química , Ondas Ultrassônicas , Animais , Cinética , Solventes/química
7.
Ultrason Sonochem ; 63: 104942, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31945564

RESUMO

The effects of the high-intensity ultrasound (HIUS) technology at the nominal powers of 300, 600, 900, and 1200 W were evaluated on the chemical stability of xylooligosaccharides (XOS) used to enrich orange juice. The ultrasound energy performance for each nominal power applied to the XOS-enriched orange juice was determined by calculating acoustic powers (W), HIUS intensity (W/cm2), and energy density (kJ/mL). Physicochemical properties (pH and soluble solid content), organic acid content (ascorbic, malic, and citric acids), total phenolic content (TPC), antioxidant activity by the FRAP (Ferric reducing ability of plasma) method, sugar (glucose, fructose, and sucrose), and XOS (xylobiose, xylotriose, xylotetraose, xylopentaose, and xylohexaose) content were determined. The pH and soluble solid content did not change after all HIUS treatments. The HIUS process severity was monitored by quantifying ascorbic acid content after the treatments. A significant linear decrease in the ascorbic acid content was observed in prebiotic orange juice with the HIUS process intensification by increasing nominal power. The malic acid and citric acid contents had similar behavior according to the HIUS process intensification. The nominal power increase from 300 to 600 W increased the concentration of both organic acids, however, the intensification up to 1200 W reduced their concentration in the functional beverage. The TPC and FRAP data corroborated with the results observed for the ascorbic acid content. However, the HIUS processing did not alter sugar and XOS contents. The XOS chromatographic profiles were not modified by the HIUS treatment and presented the same amount of all prebiotic compounds before and after the HIUS treatment. Overall, HIUS technology has been evaluated as a promising stabilization technique for prebiotic beverages enriched with XOS due to their high chemical stability to this emerging technology under severe process conditions.


Assuntos
Citrus sinensis , Manipulação de Alimentos/métodos , Glucuronatos/química , Oligossacarídeos/química , Prebióticos , Sonicação , Antioxidantes/análise , Ácido Ascórbico/análise , Cromatografia Líquida de Alta Pressão , Sucos de Frutas e Vegetais/análise , Fenóis/análise
8.
Ultrason Sonochem ; 63: 104928, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31952002

RESUMO

This study evaluated the influence of the high-intensity ultrasound (HIUS) technology on the quality parameters of a model dairy beverage (chocolate whey beverage), operating under the same energy density (5000 J/mL), but applied at different ways. Two processes were performed varying nominal power and processing time: HIUS-A (160 W and 937 s), and HIUS-B (720 W and 208 s). Our objective was to understand how different modes of application of the same HIUS energy density could influence the microstructure, droplet size distribution, zeta potential, phase separation kinetic, color parameters and mineral profile of the chocolate whey beverage. The results demonstrated that the different modes of application of the same HIUS energy density directly influenced the final quality of the product, resulting in whey beverages with distinct physical and microstructural characteristics. The HIUS-B processing was characterized as a thermal processing, since the final processing temperature reached 71 °C, while the HIUS-A processing was a non-thermal process, reaching a final temperature of 34 °C. Moreover, HIUS-B process greatly reduced the droplet size and increased the lightness value in relation to the HIUS-A processing. Both treatments resulted in whey beverages with similar phase separation kinetics and were more stable than the untreated sample. The HIUS processes did not modify the mineral content profile. Overall, the study emphasizes the versatility of the HIUS technology, highlighting that the processing must not be based only on the applied energy density, since different powers and processing times produce dairy beverages with distinct characteristics.


Assuntos
Bebidas/análise , Leite/química , Sonicação/métodos , Soro do Leite/química , Animais , Controle de Qualidade
9.
Ultrason Sonochem ; 64: 104999, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32092695

RESUMO

Passion fruit bagasse is a rich source of phenolic compounds, including piceatannol, a stilbene to which several biological activities are conferred. This work reports the application of pressurized liquid extraction (PLE) assisted by ultrasound (US) to intensify the extraction of phenolic compounds from defatted passion fruit bagasse (DPFB). PLE at different temperatures (65-75 °C) without and with different US powers (240-640 W) was performed to investigate the mechanism of the assisted process. The extracts were evaluated in terms of global, total phenolic (TP), piceatannol and total reducing sugar yields. The antioxidant capacity of the extracts was determined by FRAP and ORAC assays. PLE assisted by US increased the yields, resulting in 60% more TP and piceatannol. The observed yields suggest that the main mechanism driving PLE assisted by US from DPFB was the rise in temperature caused by the ultrasonic waves. Pearson coefficient revealed a strong correlation between antioxidant capacity and total phenolics and piceatannol yield. The three-line spline model was adequately fitted to the experimental curves, showing three extraction periods in which the recovery of TP and piceatannol was higher than 70% at the end of the falling extraction rate period. PLE assisted or not by US showed to be clean, efficient and green alternatives for the recovery of phenolic compounds. The findings of this work indicate that PLE assisted by US has a great potential to improve the extraction of bioactive compounds from natural products.


Assuntos
Celulose/química , Fracionamento Químico/métodos , Passiflora/química , Compostos Fitoquímicos/isolamento & purificação , Pressão , Sonicação , Cinética , Temperatura
10.
Int J Biol Macromol ; 155: 1060-1068, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31712155

RESUMO

Passion fruit bagasse extract (PFBE) is a rich source of polyphenols, including piceatannol. This work produced alginate (1, 2, 3 wt%) aerogel and investigated the impregnation of gallic acid (GA) and PFBE in alginate aerogel microparticles. The microparticles of ca. 100 µm in diameter were obtained by emulsion-gelation method, submitted to solvent exchange, wet impregnation (WI) and supercritical drying. Alginate aerogels derived from 1 wt% solution led to a higher GA loading and, therefore, this formulation was used to impregnate PFBE. The loading of PFBE, total phenolic, and piceatannol contents based on grams of raw aerogel were 0.62 g, 10.77 mg, and 741.85 µg, respectively, which means a loading efficiency of total phenolics and piceatannol of 47.1% and 34.7%. DSC analysis and X-ray diffraction showed that particles behave as amorphous materials and ORAC assay revealed that impregnated aerogel microparticles presented antioxidant capacity. Alginate aerogel microparticles presented as an appropriated material for drug loading, whereas WI and supercritical drying demonstrated to be useful techniques to load PBBE in aerogels.


Assuntos
Alginatos/química , Celulose/química , Portadores de Fármacos/química , Géis/química , Passiflora/química , Extratos Vegetais/química , Celulose/isolamento & purificação , Dessecação , Microesferas , Porosidade , Solubilidade , Difração de Raios X
11.
Ultrason Sonochem ; 67: 105185, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32474185

RESUMO

The aim of this study was to evaluate the effects of non-thermal and thermal high-intensity ultrasound (HIUS) treatment on the microbial and enzymatic inactivation, physicochemical properties, and kinetic stability of the raw milk by applying different energy densities (1, 3, 5, and 7 kJ/mL). Two HIUS treatments were evaluated based on different nominal powers, named HIUS-A and HIUS-B, using 100 W and 475 W, respectively. HIUS-A treatment was non-thermal processing while HIUS-B was a thermal treatment only for the energy densities of 5 and 7 kJ/mL since the final temperature was above 70 °C. The HIUS-B treatment showed to be more efficient. Log reductions up to 3.9 cycles of aerobic mesophilic heterotrophic bacteria (AMHB) were achieved. Significant reductions of the fat globule size, with diameters lower than 1 µm, better color parameters, and kinetic stability during the storage were observed. Also, HIUS-B treatment inactivated the alkaline phosphatase and lactoperoxidase. The HIUS-B treatment at 3 kJ/mL worked below 57 °C being considered a border temperature since it did not cause unwanted physicochemical effects. Furthermore, a microbial inactivation of 1.8 ± 0.1 log cycles of AMHB was observed. A proper inactivation of only the Alkaline phosphatase and a significant reduction of the fat globules sizes, which kept the milk kinetically stable during storage was achieved.


Assuntos
Leite/química , Sonicação , Animais , Bovinos , Temperatura Alta , Cinética
12.
Ultrason Sonochem ; 55: 332-340, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30857825

RESUMO

We evaluated the effect of ultrasonic power (200-600 W) and process time (1-7 min) on the recovery of a novel polysaccharide from mutamba (Guazuma ulmifolia Lam.) seeds applying high-intensity ultrasound. Ultrasound process conditions intensification gradually was removing the mucilage layer around the hydrated seeds. Then, the scanning electron micrographs showed that the mucilage was removed completely at the highest applied energy density (10,080 J/mL). Although the colour of mutamba seed mucilage (MSM) have been changed due to increase of energy density, it not affects its practical use because the MSM can be purified to remove impurities. The results obtained in this study demonstrated that the ultrasound process conditions intensification did not affect the primary structure of MSM according to ζ-potential, FTIR spectrum, and monosaccharide residues data. In conclusion, ultrasound process conditions intensification allows the full recovery of the MSM at a short process time (7 min) without altering its quality and the primary structure.

13.
RSC Adv ; 10(1): 112-121, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-35492546

RESUMO

In this study, a biorefinery for the processing of turmeric (Curcuma longa L.) based on clean and emerging technologies has been proposed. High-intensity ultrasound (HIUS) technology was evaluated as a promising technique for curcumin recovery aiming to improve its extraction yield and technological properties as a colorant. In addition, we evaluated the effects of process conditions on the turmeric biomass after the extractions. The process variables were the number of stages of extraction with ethanol (1, 3 and 5) and the solvent to feed ratio (S/F) of 3, 5, 7, 9 (w/w). The highest curcumin content (41.6 g/100 g extract) was obtained using 1 wash and a S/F of 5 w/w, while the highest curcumin yield (3.9 g/100 g unflavored turmeric) was obtained using 5 stages and a S/F of 7. The extracts obtained by solid-liquid extraction assisted by HIUS showed a yellow color (157 and 169 of yellowness index) more intense than those obtained by the pressurized liquid extraction technique (101 of yellowness index) and better yield results than low-pressure solid-liquid extraction (using the same processing time). Thus, it was possible to obtain a characteristic yellow colorant with high curcumin yield in a short process time (5 min of extraction) using HIUS technology. Besides that, SEM images and FTIR spectra demonstrated that the turmeric biomasses processed by HIUS technology were not degraded.

14.
Food Res Int ; 125: 108561, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31554042

RESUMO

Inulin-enriched apple juice was subjected to supercritical CO2 processing under different pressure levels (10, 15, and 20 MPa at 35 °C, 10 min and a 67% CO2 volume ratio) and to conventional thermal treatment (95 °C/1 min). Physicochemical properties (pH, soluble solid content, ζ-potential, particle size distribution and rheological behavior), organic acid (citric and malic) content, and phenolic compounds (UHPLC-ESI-MS/MS) were evaluated; moreover, antioxidant activity assays (DPPH and TEAC) as well as sugar content and fructo-oligosaccharide analyses (HPAEC-PAD) were performed. The increase in pressure levels reduced the particle size suspended in the functional juice. Supercritical processing was able to preserve all compounds responsible for the functional properties of the beverage as well as the natural nutritional components such as sorbitol, glucose, fructose and sucrose. The emerging technology did not reduce the antioxidant activity of the juice samples, thus maintaining their functionality. The inulin chemical profile was not altered by the supercritical CO2 processing, while in the thermally treated sample, there was a breakdown of the inulin chain into units of short-chain fructo-oligosaccharides. Overall, supercritical technology may be an interesting option for inulin-enriched apple juice processing.


Assuntos
Dióxido de Carbono/química , Manipulação de Alimentos/métodos , Alimentos Fortificados/análise , Sucos de Frutas e Vegetais/análise , Inulina/química , Malus/química , Prebióticos/análise , Temperatura Alta
15.
Food Res Int ; 116: 932-941, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30717026

RESUMO

In this work, the aqueous extract obtained from Brazilian ginseng (Pfaffia glomerata) roots (BGR), rich in beta-ecdysone and fructooligosaccharides (FOS), was powdered by spray drying and freeze drying techniques aiming to obtain a novel functional food product. The effects of these drying techniques on the chemical and nutritional quality, morphological and redispersion properties of the BGR powders were evaluated. The BGR powders obtained by both spray drying and freeze drying techniques maintained their beta-ecdysone and FOS contents after drying, demonstrating the stability of these functional compounds. It was found that the wettability of the powders obtained by different treatments was affected by the drying technique because freeze-dried particles reached the lower values (66 ±â€¯5 s) while spray-dried particles showed a greater time for dispersion into water (150 ±â€¯25 s). This behavior was mainly associated with differences between powder morphological properties since the freeze-dried particles presented a more porous structure, resulting in a greater water diffusivity into microstructure during the redispersion process. Drying process did not affect the storage stability of powders because the glass transition temperature (Tg) for both samples was approximately 160 °C at a relative humidity of 56%. Thus, both BGR powders presented adequate redispersion properties to constitute a new functional tea or even to be used as a functional ingredient in food products.


Assuntos
Bebidas , Ecdisterona/isolamento & purificação , Manipulação de Alimentos/métodos , Alimento Funcional , Valor Nutritivo , Oligossacarídeos/isolamento & purificação , Panax/química , Extratos Vegetais/isolamento & purificação , Raízes de Plantas/química , Aerossóis , Cristalografia por Raios X , Liofilização , Tamanho da Partícula , Pós , Solubilidade , Temperatura de Transição , Vitrificação , Água/análise , Molhabilidade
16.
Ultrason Sonochem ; 55: 157-164, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30853535

RESUMO

This study evaluated the nutritional profile and volatile compounds present in a novel prebiotic (inulin) soursop whey beverage, due to the effects of high-intensity ultrasound (HIUS). The prebiotic soursop whey beverage was produced and processed by non-thermal high-intensity ultrasound varying the power (0, 200, 400 and 600 W) and by high-temperature short time (72 °C for 15 s) thermal treatment. Total acidity, pH, ascorbic acid content, total phenolics compounds content, antioxidant activity, hypertensive activity, fatty acid profile, volatile organic compounds, macro and micro minerals, as well as the heavy metals in these products, were analyzed. Overall, the HIUS technology induced some positive changes in the nutritional profile of the soursop whey beverage including beneficial effects, e.g., increase of phenolic content, improvement of the antioxidant and anti-hypertensive activity and reduction of undesired minerals. Although some negative changes, such as degradation of the ascorbic acid, decrease of some minerals and production of certain volatile compounds were found, the beneficial effects were prominent, thus, opening new opportunities to develop healthy functional beverages.


Assuntos
Bebidas/análise , Inulina/química , Valor Nutritivo , Prebióticos/análise , Ultrassom , Compostos Orgânicos Voláteis/química , Soro do Leite/química , Anti-Hipertensivos/química , Anti-Hipertensivos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Ácido Ascórbico/análise , Ácidos Graxos/análise , Concentração de Íons de Hidrogênio , Minerais/análise , Fenóis/análise , Temperatura
17.
Ultrason Sonochem ; 50: 82-95, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30201331

RESUMO

In this work, we investigated the effects of the nominal ultrasonic power (160-640 W) and process time (0.5-5.0 min) on the phenolic compounds recovery and antioxidant activity from araticum peel. The individual and synergistic effects of the process variables on the phenolic recovery were estimated using a full factorial experimental design. Operating at high nominal ultrasonic powers was possible to obtain high phenolic yields and antioxidant activities at short process times (≤5 min). The HPLC-ESI-QTOF-MS/MS analysis revealed that the araticum peel sample possessed 142 phytochemicals, 123 of which had not been reported in the literature for this raw material yet. The most abundant phenolic compounds recovered were epicatechin, rutin, chlorogenic acid, catechin and ferulic acid. Thus, high-intensity ultrasound technology proved to be a simple, efficient, fast and low environmental impact method for obtaining phenolic compounds from araticum peel. In addition, araticum peel showed to be a promising source bioactive natural phenolics for further applications in the food, nutraceutical, cosmetic and pharmaceutical industries.

18.
Ultrason Sonochem ; 47: 114-121, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29908600

RESUMO

In this study, coupling of ultrasound (US) device and rotor-stator (RS), operating at low-energy densities, was studied as an alternative process to individual US and RS to produce modified starch-stabilized oil-in-water emulsions, as well as its potential use to encapsulate eugenol. To this aim, a full factorial design was employed to evaluate the effects of the US nominal power (0, 360 and 720 W) and RS nominal power (0, 150 and 300 W) on the physical properties, encapsulation efficiency and kinetic stability of emulsions produced. Firstly, the action of modified starch and eugenol onto interface oil-water was evaluated. The emulsifier was rapidly adsorbed on the interface water-sunflower oil reducing the interfacial tension from 25 to 16 mN/m, while eugenol did not show surface activity. The increase of energy density, in general, resulted in droplet size reduction, indicating the relevant role of the forces involved in the droplet breakup on emulsion stability. Coupling was more efficient on the droplets breakup producing smaller droplet size with narrower size distribution. While the coupled system work during 5 min for an energy density of 583 J/mL, the corresponding emulsification time for operating singly US and RS were 7.09 min and 17.04 min, respectively. Therefore, the main advantage associate to coupled process is the reduction of processing time to produce an emulsion with better kinetic stability.

19.
Ultrason Sonochem ; 44: 251-260, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29680610

RESUMO

In this work, we investigated the effects of the ultrasonic power (0, 200, 400 and 600 W) on non-thermal processing of an inulin-enriched whey beverage. We studied the effects of high-intensity ultrasound (HIUS) on microbial inactivation (aerobic mesophilic heterotrophic bacteria (AMHB), total and thermotolerant coliforms and yeasts and molds), zeta potential, microstructure (optical microscopy, particle size distribution), rheology, kinetic stability and color. The non-thermal processing applying 600 W of ultrasonic power was comparable to high-temperature short-time (HTST) treatment (75 °C for 15 s) concerning the inactivation of AMHB and yeasts and molds (2 vs 2 log and 0.2 vs 0.4 log, respectively), although HIUS has reached a lower output temperature (53 ±â€¯3 °C). The HIUS was better than HTST to improve beverage kinetic stability, avoiding phase separation, which was mainly attributed to the decrease of particles size, denaturation of whey proteins and gelation of polysaccharides (inulin and gellan gum). Thus, non-thermal processing by HIUS seems to be an interesting technology for prebiotic dairy beverages production.


Assuntos
Bebidas , Viabilidade Microbiana , Prebióticos , Ondas Ultrassônicas , Soro do Leite , Alimento Funcional , Temperatura Alta , Tamanho da Partícula , Desnaturação Proteica , Sonicação
20.
Ultrason Sonochem ; 42: 1-10, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29429649

RESUMO

This study presents the emerging high-intensity ultrasound (HIUS) processing as a non-thermal alternative to high-temperature short-time pasteurization (HTST). Chocolate milk beverage (CMB) was subjected to different ultrasound energy densities (0.3-3.0 kJ/cm3), as compared to HTST pasteurization (72 °C/15 s) aimed to verify the effect of the HIUS processing on the microbiological and physicochemical characteristics of the beverage. The application of HIUS at an energy density of 3.0 kJ/cm3 was able to reduce 3.56 ±â€¯0.02 logarithmic cycles in the total aerobic counts. In addition, the ultrasound energy density affected the physical properties of the beverage as the size distribution of fat globule and rheological behavior, as well as the chemical properties such as antioxidant activity, ACE inhibitory activity, fatty acid profile, and volatile profile. In general, the different energetic densities used as a non-thermal method of pasteurization of CMB were more effective when compared to the conventional pasteurization by HTST, since they improved the microbiological and physicochemical quality, besides preserving the bioactive compounds and the nutritional quality of the product.


Assuntos
Leite/química , Leite/microbiologia , Pasteurização/métodos , Sonicação , Animais , Ácidos Graxos/análise , Qualidade dos Alimentos , Fenômenos Ópticos , Reologia , Compostos Orgânicos Voláteis/análise
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