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1.
Food Res Int ; 179: 113971, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38342525

RESUMO

Cabernet Sauvignon (CS) and a combination of Cabernet Sauvignon with blueberry extract (CS + B), were spray dried (using maltodextrin DE10, 13.5% w/w as a carrier) to obtain two types of phenolic-rich powders. The addition of blueberry to CS increased phenolic compounds content by 16%. Eight chocolate formulations were obtained by modifying concentrations of cocoa solids, cocoa butter, and sugar. Six of the samples were added with 10% w/w of phenolic-rich powder, while two of them remained as powder-free controls. The anthocyanin and flavan-3-ol profiles of chocolates were determined by HPLC-DAD-MS and HPLC-MS, respectively. In addition, the sensory dynamic profile of samples was assessed by Temporal Dominance of Sensations with a consumer panel. Results showed that the addition of phenolic-rich powders produced a significant increase in the anthocyanin composition obtaining the highest anthocyanin content in the white chocolate added with CS + B powder. On the other hand, adding 10% of CS powder to dark chocolate (55% cocoa pellets) did not result in a significant increase in phenolic compounds. The addition of phenolic-rich powders to chocolates influenced visual color, texture, and taste, leading to new products with distinctive characteristics and increasing the possibility of using phenolic-rich powders as innovative and healthy ingredients.


Assuntos
Mirtilos Azuis (Planta) , Cacau , Chocolate , Extratos Vegetais , Vinho , Chocolate/análise , Pós , Antocianinas , Fenóis/análise
2.
Food Sci Technol Int ; 27(2): 135-144, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32659122

RESUMO

Berry fruits are well recognized for health-promoting constituents due to their properties of free radical scavengers which confer antioxidant activity against cellular oxidation reactions. Elderberry fruit contains one of the highest levels of anthocyanins. The objective of this work was to evaluate the storage stability of total monomeric anthocyanins, cyanidin-3-glucoside (one of two major anthocyanins in elderberry), and color parameters in freeze-dried elderberry encapsulated with a low proportion of different carriers (Maltodextrin, Capsul™, Promitor ™, and κ-carrageenan). Encapsulated samples were stored at two different water activities (aw) 0.10-0.20 and 0.43 at 38 ℃ for 90 days and evaluated for the content of monomeric anthocyanins, cyanidin-3-glucoside, color parameters, and physical characteristics. Freeze-dried powders remained free-flowing during storage at 38 ℃ with aw 0.12-0.20, but agglomeration occurred at aw = 0.43. Total anthocyanins and color parameter a* (redness) remained unchanged during storage at the lower aw. Glass transition temperatures (Tg) were determined and mostly correlated with observed physical phenomena. The powders had a very high total monomeric anthocyanin contents as high as 13 mg/g (cyanidin-3-glucoside). The addition of encapsulants in low proportions allowed the researchers to obtain elderberry powders with a very high concentration of total monomeric anthocyanins. aw plays a key role in all stability parameters studied.


Assuntos
Antocianinas , Armazenamento de Alimentos , Liofilização , Sambucus , Antocianinas/química , Antioxidantes , Armazenamento de Alimentos/métodos , Frutas/química , Sambucus/química
3.
J Dairy Res ; 86(3): 354-360, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31328709

RESUMO

A commercial drinkable yogurt with and without 4% of added trehalose (as cell protectant) was spray-dried obtaining a powder with low water activity (aw). Total bacterial count in the powder was between 8.48-8.90 log cfu/g. The dried yogurt was stored: (i) at 38 °C and aw = 0.33; (ii) at 38 °C in hermetically sealed flasks (aw = 0.21/0.22); (iii) in a cyclic temperature chamber (10-20 °C) in hermetically sealed flasks (aw = 0.21/0.22). Whole milk was then fermented by adding an inoculum of spray-dried yogurt after storage under these different conditions. The kinetics of acidification showed the presence of a lag time which was strongly dependent on storage conditions. The data was fitted with a logistic type equation from which the lag time was calculated. To evaluate structural differences among samples, Fourier Transform Infrared spectra (FTIR) were recorded. Partial Least Squares (PLS) models enabled a good correlation between lag time of fermentation and FTIR spectra. The lag time for yogurt powder stored at aw about 0.21/0.22 and cyclic temperature 10-20 °C remained approximately constant over the 12 weeks of storage, while all the other conditions resulted in a dramatic increase. The addition of trehalose had a small influence on lag time and, therefore, as a protectant of lactobacilli.


Assuntos
Armazenamento de Alimentos/métodos , Leite/microbiologia , Iogurte/microbiologia , Animais , Contagem de Colônia Microbiana , Dessecação/métodos , Fermentação , Lactobacillus/efeitos dos fármacos , Lactobacillus/fisiologia , Pós , Fatores de Tempo , Trealose/administração & dosagem , Iogurte/análise
4.
Molecules ; 23(4)2018 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-29642422

RESUMO

Red wine polyphenols are known for their implications for human health protection, although they suffer from high instability. For this reason, a red wine powder was prepared by freeze-drying encapsulation in maltodextrin/arabic gum matrix, and its composition was determined by means of high-performance liquid chromatography coupled quadrupole time-of-flight mass spectrometry (HPLC-MS-QTOF). More than thirty polyphenols, including anthocyanins, flavanols, flavonols, phenolic acids and stilbenoids, were identified. Some of the main quantified polyphenols were: malvidin-3-O-glucoside, malvidin 3-O-(6″-acetyl-glucose), petunidin-3-O-glucoside, quercetin-3-O-glucuronide, syringenin-3-O-glucoside, epicatechin, gallic acid and syringic acid. The biological activity of this de-alcoholized and encapsulated red wine on human neuroblastoma SH-SY5Y cells was studied. The results showed that the encapsulated red wine powder has active redox properties, as verified by performing reactive oxygen species (ROS) analysis utilizing a neuronal model. This could help explain its action against the neurotoxicity induced by 6-hydroxydopamine (6-OHDA).


Assuntos
Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Polifenóis/farmacologia , Vinho/análise , Cápsulas , Linhagem Celular , Sobrevivência Celular , Cromatografia Líquida de Alta Pressão , Goma Arábica/química , Humanos , Espectrometria de Massas , Modelos Biológicos , Neurônios/citologia , Neurônios/metabolismo , Fármacos Neuroprotetores/química , Oxidopamina/efeitos adversos , Polifenóis/química , Polissacarídeos/química , Pós , Espécies Reativas de Oxigênio/metabolismo
5.
Reprod Biomed Online ; 36(5): 500-507, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29422429

RESUMO

Heat transfer during cooling and warming is difficult to measure in cryo-devices; mathematical modelling is an alternative method that can describe these processes. In this study, we tested the validity of one such model by assessing in-vitro development of vitrified and warmed bovine oocytes after parthenogenetic activation and culture. The viability of oocytes vitrified in four different cryo-devices was assessed. Consistent with modelling predictions, oocytes vitrified using cryo-devices with the highest modelled cooling rates had significantly (P < 0.05) better cleavage and blastocyst formation rates. We then evaluated a two-step sample removal process, in which oocytes were held in nitrogen vapour for 15 s to simulate sample identification during clinical application, before being removed completely and warmed. Oocytes exposed to this procedure showed reduced developmental potential, according to the model, owing to thermodynamic instability and devitrification at relatively low temperatures. These findings suggest that cryo-device selection and handling, including method of removal from nitrogen storage, are critical to survival of vitrified oocytes. Limitations of the study include use of parthenogenetically activated rather than fertilized ova and lack of physical measurement of recrystallization. We suggest mathematical modelling could be used to predict the effect of critical steps in cryopreservation.


Assuntos
Criopreservação/veterinária , Técnicas de Maturação in Vitro de Oócitos/veterinária , Animais , Bovinos , Criopreservação/métodos , Desenvolvimento Embrionário , Feminino , Técnicas de Maturação in Vitro de Oócitos/métodos , Modelos Teóricos , Oócitos , Temperatura , Termodinâmica , Vitrificação
6.
Cryobiology ; 52(1): 157-60, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16332364

RESUMO

The influence of different yeast (Saccharomyces cerevisiae) cellular fractions was studied in an attempt to gain knowledge on the feasibility of trehalose crystallization in yeast cells. Certain constituents of S. cerevisiae cells inhibited/delayed trehalose crystallization upon humidification at high relative humidities.


Assuntos
Citoplasma/metabolismo , Saccharomyces cerevisiae/metabolismo , Trealose/antagonistas & inibidores , Trealose/química , Extratos Celulares/farmacologia , Cristalização , Temperatura , Trealose/metabolismo
7.
Biotechnol Prog ; 20(4): 1220-4, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15296451

RESUMO

The purpose of the present work was to study the effects of simulated sunlight conditions on enzyme inactivation and structural damage in dehydrated glassy systems. Freeze-dried samples containing different enzymes (lactase, invertase, lysozyme and amyloglucosidase) were exposed to light using a medium-pressure metal halide HPA 400 W lamp. After 1 h of light exposure, the samples showed a significant reduction (more than 50%) in the denaturation peak area as analyzed by DSC, and this could be attributed to protein denaturation. For most of the pure enzymes, the loss of enzymic activity after 1 h of light exposure was around 50%. In the case of enzymes included in anhydrous model systems (trehalose, raffinose, maltodextrin, and dextran), the remaining activity also decreased dramatically during the light treatment. We showed that the light exposure in dehydrated systems generated both the loss of enzymic activity and structural changes such as denaturation (observed by DSC) and protein fragmentation and aggregation (observed by electrophoresis). Overall, we can conclude that a short exposure to the light produces dramatic changes in the enzymic activity in dehydrated systems with or without protective matrices.


Assuntos
Enzimas/química , Vidro , Proteínas/química , Luz Solar , Varredura Diferencial de Calorimetria , Eletroforese em Gel de Poliacrilamida , Estabilidade Enzimática , Conformação Proteica
8.
Braz. j. microbiol ; 32(2): 123-126, Apr.-Jun. 2001. tab, graf
Artigo em Inglês | LILACS | ID: lil-391992

RESUMO

No estudo avaliou-se o efeito da temperatura, concentração e tempo de contato na atividade antifúngica do óleo essencial do cravo disperso em solução concentrada de açúcar. Os ensaios foram feitos a 21ºC e a 37ºC, utilizando suspensão de óleo essencial de 0.2 a 0.8 per center v/v. Os microorganismos utilizados foram Candida albicans, Penicillium citrinum, Aspergillus niger e Trichophyton mentagrophytes. A melhor atividade fungicida ocorreu a 37ºC, onde um minuto de contato foi suficiente para matar uma população de 106 u.f.c./ml de Candida albicans. Não obstante, P. citrinum, A. niger, T. mentagrophytes foram mais resistentes, embora uma importante ação letal da essência tenha sido observada. Em 60 minutos, o óleo essencial de cravo (0,4 per center v.v.) em solução concentrada de açúcar reduziu em 99,6 per center um inóculo de 106 u.f.c./ml de T. mentagrophytes. O efeito letal do óleo essencial de cravo sobre C. albicans, após 2 minutos de contato, foi semelhante ao de desinfectantes comumente usados em hospitais, como povidona-iodo e cloroxilenol.


Assuntos
Ensaios Enzimáticos Clínicos , Eugenol , Fungos , Técnicas In Vitro , Métodos , Soluções
9.
Rev. argent. cir ; 65(6): 231-7, dic. 1993. ilus
Artigo em Espanhol | LILACS | ID: lil-127532

RESUMO

En 10 años se efectuaron 106 resecciones hepáticas en 99 pacientes, en 5 se realizaron dos y en 1 tres. Veintinueve fueron por patología benigna, 4 por traumatismo y 73 por patología maligna (33 por neoplasia primaria y 40 por metástasis). Las complicaciones intra-operatorias fueron 1 paro cardíaco y 3 lesiones venosas leves sin mortalidad (3,8//). Complicaciones post-operatoria ocurrieron en 29 pacientes (27,5//). No hubo mortalidad por patología benigna. La mortalidad global fue de 10,3// (11/106). En la cirugía electiva, la mortalidad fue del 1,6// (1/61) en las resecciones hepáticas puras y del 15,4//(6/39) cuando se asoció a otra cirugía mayor oncológica, mientras que en las resecciones de urgencia fue del 66,7// (4/6). La supervivencia media de los resecados con criterio curativo por hepatocarcinomas y por metástasis de cáncer colorrectal, fue de 46 y 38,5 meses respectivamente. Se concluye que las resecciones hepáticas electivas, no asociadas a otra cirugía mayor tuvieron en nuestra experiencia baja mobimortalidad y proporcionaron supervivencias importantes y de buena calidad


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Adolescente , Adulto , Pessoa de Meia-Idade , Hepatectomia/estatística & dados numéricos , Análise de Sobrevida , Hepatectomia , Hepatectomia/mortalidade , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/cirurgia , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Reoperação/estatística & dados numéricos , Estudos Retrospectivos
10.
Rev. argent. cir ; 65(6): 231-7, dic. 1993. ilus
Artigo em Espanhol | BINACIS | ID: bin-25131

RESUMO

En 10 años se efectuaron 106 resecciones hepáticas en 99 pacientes, en 5 se realizaron dos y en 1 tres. Veintinueve fueron por patología benigna, 4 por traumatismo y 73 por patología maligna (33 por neoplasia primaria y 40 por metástasis). Las complicaciones intra-operatorias fueron 1 paro cardíaco y 3 lesiones venosas leves sin mortalidad (3,8//). Complicaciones post-operatoria ocurrieron en 29 pacientes (27,5//). No hubo mortalidad por patología benigna. La mortalidad global fue de 10,3// (11/106). En la cirugía electiva, la mortalidad fue del 1,6// (1/61) en las resecciones hepáticas puras y del 15,4//(6/39) cuando se asoció a otra cirugía mayor oncológica, mientras que en las resecciones de urgencia fue del 66,7// (4/6). La supervivencia media de los resecados con criterio curativo por hepatocarcinomas y por metástasis de cáncer colorrectal, fue de 46 y 38,5 meses respectivamente. Se concluye que las resecciones hepáticas electivas, no asociadas a otra cirugía mayor tuvieron en nuestra experiencia baja mobimortalidad y proporcionaron supervivencias importantes y de buena calidad


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Hepatectomia/estatística & dados numéricos , Análise de Sobrevida , Hepatectomia/mortalidade , Hepatectomia/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/epidemiologia , Reoperação/estatística & dados numéricos , Recidiva Local de Neoplasia/cirurgia , Recidiva Local de Neoplasia/epidemiologia , Estudos Retrospectivos
11.
Rev. argent. cir ; 65(5): 146-52, nov.1993. ilus
Artigo em Espanhol | LILACS | ID: lil-127500

RESUMO

Desde 1985 a junio de 1991, 13 de 15 pacientes (87//) con colangiocarcinoma hiliar fueron resecados. La resección completa se logró en 9, (69//) de las resecciones y al 60// de los pacientes remitidos. Se efectuaron 3 resecciones locales amplias y 6 que además necesitaron de resecciones hepáticas mayores. En 4 casos se incluyó la resección del lóbulo caudado y en 2 fueron necesarias resecciones parciales de la vena porta remanente. En las resecciones completas (9) la morbilidad fue del 55,5// y la mortalidad del 22,2//. Los completamente resecados sobrevivieron entre 13 y 50 meses. Los otros entre 3 y 13 meses. Un paciente con una forma papilar temprana lleva 30 meses libres de síntomas. Todos los fallecidos tuvieron recidiva local y 3 metástasis a distancia. La resección completa del tumor brinda la mayor supervivencia y de mejor calidad


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Adenoma de Ducto Biliar/cirurgia , Neoplasias dos Ductos Biliares/cirurgia , Procedimentos Cirúrgicos do Sistema Biliar , Adenoma de Ducto Biliar/diagnóstico , Adenoma de Ducto Biliar/mortalidade , Neoplasias dos Ductos Biliares/classificação , Neoplasias dos Ductos Biliares/diagnóstico , Carcinoma/classificação , Carcinoma/diagnóstico , Carcinoma/cirurgia , Colangiografia , Colangiopancreatografia Retrógrada Endoscópica/normas , Análise de Sobrevida
12.
Rev. argent. cir ; 65(5): 146-52, nov. 1993. ilus
Artigo em Espanhol | BINACIS | ID: bin-25163

RESUMO

Desde 1985 a junio de 1991, 13 de 15 pacientes (87//) con colangiocarcinoma hiliar fueron resecados. La resección completa se logró en 9, (69//) de las resecciones y al 60// de los pacientes remitidos. Se efectuaron 3 resecciones locales amplias y 6 que además necesitaron de resecciones hepáticas mayores. En 4 casos se incluyó la resección del lóbulo caudado y en 2 fueron necesarias resecciones parciales de la vena porta remanente. En las resecciones completas (9) la morbilidad fue del 55,5// y la mortalidad del 22,2//. Los completamente resecados sobrevivieron entre 13 y 50 meses. Los otros entre 3 y 13 meses. Un paciente con una forma papilar temprana lleva 30 meses libres de síntomas. Todos los fallecidos tuvieron recidiva local y 3 metástasis a distancia. La resección completa del tumor brinda la mayor supervivencia y de mejor calidad


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Adenoma de Ducto Biliar/cirurgia , Neoplasias dos Ductos Biliares/cirurgia , Procedimentos Cirúrgicos do Sistema Biliar/métodos , Adenoma de Ducto Biliar/diagnóstico , Adenoma de Ducto Biliar/mortalidade , Neoplasias dos Ductos Biliares/classificação , Neoplasias dos Ductos Biliares/diagnóstico , Colangiografia/métodos , Colangiopancreatografia Retrógrada Endoscópica/normas , Carcinoma/cirurgia , Carcinoma/classificação , Carcinoma/diagnóstico , Análise de Sobrevida
13.
J Food Prot ; 51(5): 419-423, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-30978901

RESUMO

This paper compiles recent data on the theoretical prediction of the water activity (aw) of selected saturated salt solutions, unsaturated NaCl and LiCl solutions, and H2SO4 solutions. These results are presented in tabular form in such a way that they can be safely used as reference sources for aw determination in the range of microbial growth (i.e. about 0.57-0.97) and at different temperatures.

14.
J Food Prot ; 51(7): 542-546, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30991593

RESUMO

Development of a time-temperature integrator based on color changes produced by the chemical reaction between reducing sugars (i.e. fructose, glucose, lactose) and 1-lysine (Maillard's reaction), is described. The indicator is particularly suitable to provide an objective method for confirming that a given temperature in the inner part of a meat product cooked in water in hermetically sealed packages, was achieved. This is needed to ascertain inactivation of the foot and mouth disease (FMD) virus and is required for meat imported from countries in which the FMD virus is present. The indicator is placed at the surface of the meat package and will avoid the need of opening the package for inspection.

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