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Métodos Terapêuticos e Terapias MTCI
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1.
J Agric Food Chem ; 58(24): 12585-91, 2010 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-21082861

RESUMO

Determination of the botanical origin of raw spirit used for alcoholic beverage production is of great importance for rectifying units, control laboratories, and proper product labeling. Raw spirit samples (138) produced from rye, corn, and potato were analyzed using a solid phase microextraction-mass spectrometry (SPME-MS) method, which involved volatiles preconcentration by SPME with subsequent volatile fraction characterization by MS without particular compounds separation by GC. Obtained data were treated using principal component analysis and linear discriminant analysis (LDA) to test the possibility of sample classification. SPME sampling conditions allowed rapid extraction in 2 min at 50 °C using a carboxen/divinylbenzene/polydimethylsiloxane fiber, followed by rapid MS analysis. Use of LDA made possible the classification of raw spirits based on the material they were produced from. The classification ability of the developed SPME-MS method was 100%, whereas its prediction ability was 96%.


Assuntos
Bebidas Alcoólicas/análise , Espectrometria de Massas/métodos , Secale/química , Solanum tuberosum/química , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise , Zea mays/química , Bebidas Alcoólicas/normas , Controle de Qualidade , Compostos Orgânicos Voláteis/isolamento & purificação
2.
Int J Food Microbiol ; 144(1): 193-8, 2010 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-20937538

RESUMO

Mead fermentation is a time-consuming process, often taking several months to complete. Despite of the use of starter cultures several problems still persist such as lack of uniformity of the final products, slow or premature fermentation arrest and the production of off-flavors by yeast. Thus the aim of this study was to optimize mead production through the use of an appropriate honey-must formulation to improve yeast performance alcoholic fermentation and thereby obtain a high quality product. Honey-must was centrifuged to reduce insoluble solids, pasteurized at 65°C for 10 min, and then subjected to different conditions: nitrogen supplementation and addition of organic acids. Although the addition of diammonium phosphate (DAP) reduced fermentation length, it did not guarantee the completeness of the fermentation process, suggesting that other factors could account for the reduced yeast activity in honey-must fermentations. Sixteen yeast-derived aroma compounds which contribute to the sensorial quality of mead were identified and quantified. Global analysis of aromatic profiles revealed that the total concentration of aroma compounds in meads was higher in those fermentations where DAP was added. A positive correlation between nitrogen availability and the levels of ethyl and acetate esters, associated to the fruity character of fermented beverages, was observed whereas the presence of potassium tartrate and malic acid decreased, in general, their concentration. This study provides very useful information that can be used for improving mead quality.


Assuntos
Bebidas Alcoólicas/microbiologia , Fermentação , Microbiologia de Alimentos , Mel , Saccharomyces cerevisiae/metabolismo , Bebidas Alcoólicas/análise , Bebidas Alcoólicas/normas , Concentração de Íons de Hidrogênio , Saccharomyces cerevisiae/crescimento & desenvolvimento , Paladar , Fatores de Tempo
3.
Int J Environ Res Public Health ; 6(8): 2090-101, 2009 08.
Artigo em Inglês | MEDLINE | ID: mdl-19742208

RESUMO

Four homemade (artisanally manufactured and unrecorded) and seven commercial (industrially manufactured and taxed) alcohol products from Vietnam were collected and chemically analyzed for toxicologically relevant substances. The majority of both types had alcohol contents between 30 and 40% vol. Two homemade samples contained significantly higher concentrations of 45 and 50% vol. In one of these homemade samples the labeled alcoholic strength was exceeded by nearly 20% vol. All other analyzed constituents of the samples (e.g., methanol, acetaldehyde, higher alcohols, esters, metals, anions) were found in concentrations that did not pose a threat to public health. A peculiarity was a homemade sample of alcohol with pickled snakes and scorpions that contained 77% vol of alcohol, allegedly used as traditional Chinese medicine. Based on this small sample, there is insufficient evidence to conclude that alcohol quality, beyond the effects of ethanol, has an influence on health in Vietnam. However, future research with larger samples is needed.


Assuntos
Bebidas Alcoólicas/normas , Substâncias Perigosas/análise , Bebidas Alcoólicas/análise , Qualidade de Produtos para o Consumidor , Vietnã
4.
Anal Chim Acta ; 628(2): 222-9, 2008 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-18929011

RESUMO

In the present study the qualitative and quantitative determination of diterpenoids in commercial distilled gin was carried out. This widely consumed juniper-based spirit is aromatized using Juniper (Juniperus communis) berries. Although juniper reportedly contains several diterpenic compounds, no studies have addressed the diterpenic composition of juniper-based spirits or beverages. With this objective, here we followed a multilevel factorial experimental design to optimize a direct immersion-solid phase microextraction (DI-SPME) method coupled to gas chromatography/mass spectrometry and analyzed eight commercial brands of gin. With total concentrations ranging from 10 to 190 microg L(-1), manool, manoyl oxide and trans-totarol were the most abundant diterpenoids of the 10 identified or tentatively identified at variable but not negligible concentrations in the distilled gin samples. The diterpenic composition allowed the brands to be differentiated. This indicates that these compounds contribute to the sensory characteristics of the distinct commercial brands, thus guaranteeing the authenticity and consequently the quality of the product.


Assuntos
Bebidas Alcoólicas/análise , Diterpenos/isolamento & purificação , Bebidas Alcoólicas/classificação , Bebidas Alcoólicas/normas , Cromatografia Gasosa-Espectrometria de Massas , Juniperus/química , Extratos Vegetais/isolamento & purificação , Padrões de Referência , Microextração em Fase Sólida , Fatores de Tempo
5.
J Chromatogr A ; 718(1): 99-106, 1995 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-8556168

RESUMO

Characteristic HPLC profiles of fresh and aged aloe solutions, detected at 360 and 220 nm, are presented and compared. Several aloe constituents (aloesin, aloeresin A, hydroxyaloin, aloin A and B and aloinoside A and B) were simultaneously separated and identified. The determination of aloin is described (detection limit 0.15 ppm) and discussed. In aloe-based alcoholic beverages, the aloins could not be detected, owing to their instability and degradation in solution; this is discussed in relation to the EEC Council Directive 88/388, which fixed the values of maximum allowable concentrations for aloin in food and beverages. Instead of aloin, other aloe compounds (e.g., aloeresin A or aloesin) should perhaps be used as an index of the presence of aloe in alcoholic beverages.


Assuntos
Bebidas Alcoólicas/normas , Aloe/química , Emodina/análogos & derivados , Plantas Medicinais , Bebidas Alcoólicas/análise , Cromatografia Líquida de Alta Pressão , Cromonas/análise , Emodina/análise , União Europeia , Aromatizantes/análise , Aromatizantes/normas , Glucosídeos/análise , Cinética , Estrutura Molecular , Espectrofotometria
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