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1.
Food Chem ; 171: 421-5, 2015 Mar 15.
Article in English | MEDLINE | ID: mdl-25308689

ABSTRACT

Free proline was significantly (p<0.05) lower compared to that of other honeys from the atlantic forest, caatinga and cerrado biomes. Honeys from the atlantic forest and cerrado had a significantly (p<0.05) lower HMF than angico. Fructose and glucose in angico honeys were significantly (p<0.05) higher than those from caatinga. Mean values for turanose, nigerose, sucrose, isomaltose, maltotriose, panose and raffinose in angico were significantly (p<0.05) different from honeys from the atlantic forest and caatinga. Use of cluster analysis permitted the three kinds of honey to be grouped independently. Angico was closest to caatinga honey, but both were significantly (p<0.05) different from other atlantic forest honey. GC/SNIFFING showed that linalool oxide, 2-ethyl hexanol, phenylethanol, and phenylacetic acid may be important contributors to the flavour of angico honey.


Subject(s)
Honey/analysis , Mass Spectrometry , Chromatography, Gas , Fructose , Glucose , Principal Component Analysis , Volatile Organic Compounds/analysis , Volatile Organic Compounds/isolation & purification
2.
Food Chem ; 149: 159-69, 2014 Apr 15.
Article in English | MEDLINE | ID: mdl-24295690

ABSTRACT

Sixteen polycyclic aromatic hydrocarbons (PAHs) have been identified in Brazilian sugarcane spirits. Contamination sources are: sugarcane burn before harvest and petroleum derivatives. PAHs concentration in spirits produced from burned cane was about 2-3 times higher than those from unburned cane. Benzo(a)pyrene (BaP) is present at less than 1%, and therefore is not a representative marker of cachaça contamination by PAHs. Ethyl carbamate (EC) is produced during both fermentation and distillation. During distillation, cupric ions may catalyse the conversion of cyanide to EC. In discontinuous distillation, the use of the heart fraction for bottling cachaça considerably decreases its concentration. In the continuous process, in which there is no separation of distillate, it is highly recommended to couple cooling devices and reflux systems to the distillation column. Consumers are at a greater risk of EC exposure from cachaça than from any other spirit.


Subject(s)
Alcoholic Beverages/analysis , Food Contamination/analysis , Polycyclic Aromatic Hydrocarbons/analysis , Saccharum/chemistry , Urethane/analysis , Brazil , Food Contamination/statistics & numerical data
3.
Arch. latinoam. nutr ; Arch. latinoam. nutr;62(4): 389-390, dic. 2012. ilus, tab
Article in Spanish | LILACS | ID: lil-714894

ABSTRACT

Volatiles from aqueous extract of peppermint commercial sachets were investigated through gas chromatography/flame ionization detection (GC/FID) and GC/mass spectrometry (MS). Samples were prepared under similar conditions as in homemade tea. Volatiles were isolated using solid phase extraction method (SPE) with Porapak Q trap followed by desorption with acetone. Estimated mean values for short and medium chain carboxylic acids (C2- C12) and ketones lay in the range of 50-64 μg kg-1 whilst aliphatic alcohols and acyclic hydrocarbons had values lower than 6 μg kg-1. The major volatiles were terpenes (275-382 μg kg-1) that reached 89 % of the total composition. A total of 16 compounds, among them dodecane, acetoin, acetol, citral, geraniol and octanoic acid have been described by the first time in peppermint tea. These findings could be attributed to the different analytical approach employed, mainly to the use of different extraction/pre-concentration techniques. Given the apparently lower proportion of terpenes in the aqueous extract it may be that the chemical properties of the peppermint essential oil are not entirely reproduced with homemade tea.


Estudo da composição da fração volátil do extrato aquoso de sachês de hortelã pimenta (Mentha piperita L.) através da extração em fase sólida. O princípio desse trabalho foi investigar a fração volátil do extrato aquoso de sachês comerciais de hortelã pimenta usando cromatografia gasosa com detectores de ionização em chama e de massas. As amostras foram preparadas em condições similares às usadas para o preparo do chá caseiro. Os compostos voláteis foram isolados via método de extração em fase sólida com adsorvente Porapak Q e eluídos com acetona. Uma estimativa dos valores médios dos ácidos carboxílicos de cadeias média e curta ficou na faixa de 50-64 μg kg-1, enquanto alcoóis alifáticos e hidrocarbonetos acíclicos tiveram valores menores do que 6 μg kg-1. Os terpenos (275-382 μg kg-1) foram os compostos majoritários alcançando 89 % dos sólidos totais. Um total de 16 compostos voláteis, entre eles, dodecano, acetoína, acetol, citral, geraniol e ácido octanóico foram descritos pela primeira vez no chá de hortelã pimenta. Esses resultados poderiam ser atribuídos aos diferentes métodos analíticos empregados, principalmente devido ao uso de diferentes técnicas de extração e pré-concentração. Em função da proporção menor de terpenos no extrato aquoso é razoável especular que as propriedades químicas do óleo essencial da hortelã pimenta não sejam totalmente reproduzidas com o consumo do chá caseiro.


Subject(s)
Mentha piperita/chemistry , Oils, Volatile/analysis , Plant Extracts/analysis , Solid Phase Extraction/standards , Tea/chemistry , Volatile Organic Compounds/analysis , Carboxylic Acids/analysis , Flame Ionization , Gas Chromatography-Mass Spectrometry , Ketones/analysis , Mass Spectrometry/standards , Plant Leaves/chemistry , Terpenes/analysis
4.
Arch Latinoam Nutr ; 62(4): 389-92, 2012 Dec.
Article in English | MEDLINE | ID: mdl-24020260

ABSTRACT

Volatiles from aqueous extract of peppermint commercial sachets were investigated through gas chromatography/flame ionization detection (GC/FID) and GC/mass spectrometry (MS). Samples were prepared under similar conditions as in homemade tea. Volatiles were isolated using solid phase extraction method (SPE) with Porapak Q trap followed by desorption with acetone. Estimated mean values for short and medium chain carboxylic acids (C2-C12) and ketones lay in the range of 50-64 microg kg(-1) whilst aliphatic alcohols and acyclic hydrocarbons had values lower than 6 microg kg(-1). The major volatiles were terpenes (275-382 microg kg(-1)) that reached 89 % of the total composition. A total of 16 compounds, among them dodecane, acetoin, acetol, citral, geraniol and octanoic acid have been described by the first time in peppermint tea. These findings could be attributed to the different analytical approach employed, mainly to the use of different extraction/pre-concentration techniques. Given the apparently lower proportion of terpenes in the aqueous extract it may be that the chemical properties of the peppermint essential oil are not entirely reproduced with homemade tea.


Subject(s)
Mentha piperita/chemistry , Oils, Volatile/analysis , Plant Extracts/analysis , Solid Phase Extraction/standards , Tea/chemistry , Volatile Organic Compounds/analysis , Carboxylic Acids/analysis , Flame Ionization , Gas Chromatography-Mass Spectrometry , Ketones/analysis , Mass Spectrometry/standards , Plant Leaves/chemistry , Terpenes/analysis
5.
J Agric Food Chem ; 50(26): 7616-21, 2002 Dec 18.
Article in English | MEDLINE | ID: mdl-12475279

ABSTRACT

The aim of this work was to characterize the volatile fractions of two Brazilian honeys known as caju and marmeleiro. The volatile components were isolated by a column extraction technique using acetone as the extraction solvent. Totals of 59 and 36 volatile compounds were definitely or tentatively identified in the caju and marmeleiro honeys, respectively, using reference substances, mass spectral libraries, and the odor qualities of the compounds eluted from the GC column. Aroma extraction dilution analysis allowed the tentative identification of furfuryl mercaptan, benzyl alcohol, delta-octalactone, gamma-decalactone, eugenol, benzoic acid, isovaleric acid, phenylethyl alcohol, and 2-methoxyphenol as impact volatile compounds in the caju honey. In the marmeleiro honey, only isovaleric acid, gamma-decalactone, benzoic acid, and vanillin were considered to be potent odorants. This study showed that the medium- to high-boiling volatile compounds are important contributors to the characteristic aroma of these honeys.


Subject(s)
Anacardium , Croton , Honey/analysis , Odorants/analysis , Acetone , Adult , Brazil , Chromatography, Gas , Gas Chromatography-Mass Spectrometry , Humans , Smell , Volatilization
6.
Arch Latinoam Nutr ; 51(1): 95-9, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11515239

ABSTRACT

Coffee is basically consumed for the pleasure given by its taste and aroma, that is, the quality and acceptance of the coffee beverage are directly related to its sensorial characteristics. Thus, nowadays coffee quality is basically evaluated by sensorial analysis. However, together with this kind of analysis, it should be important to have available more objective chemical methods to assess coffee quality. One possible approach could be based on the analysis of chlorogenic acids (CGA), since they are considered precursors of coffee flavour and pigments during roasting. In the present work, high performance liquid chromatography (HPLC) analysis of chlorogenic acids was applied to six different Brazilian arabica green coffee samples which were previously characterised by sensorial analysis. The results showed the potential to correlate the chemical data, evaluated by the Principal Components Analysis (PCA) statistical method, with sensorial analysis in order to discriminate the quality of the samples. It was observed that the 3,4-dicaffeoylquinic (3,4-diCQA) and 3,5-dicaffeoylquinic (3,5-diCQA) isomers are very important for grouping the coffees into good and bad samples.


Subject(s)
Chlorogenic Acid/analysis , Coffee/chemistry , Brazil , Coffee/classification , Coffee/standards , Quality Control
7.
J Agric Food Chem ; 48(9): 3935-8, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10995294

ABSTRACT

The effect of heated quercetin (400 mg/kg of oil) or 5-caffeoylquinic acid (5-CQA) and the presence of ferric ion (2.2 mg/kg of oil) on the stability of soya oil oxidized in an oxidative stability index (OSI) instrument was investigated. After heating the phenolic at 100 degrees C or 150 degrees C, the OSI values of treated oils were not significantly (p < 0.001) different, whereas, at 200 degrees C, the values decreased significantly with addition of quercetin, but not with 5-CQA. However, the antioxidative activity of quercetin remained significantly greater than that of 5-CQA. The antioxidative potency of quercetin was reduced significantly by addition of ferric palmitate (FP), but that of 5-CQA was not. Reaction between the ortho-dihydroxy groups of the quercetin and ferric ion may reduce the number of hydroxyls available to react with free radicals. Chelating action of 5-CQA might be provided by ortho-dihydroxy grouping of the quinic acid moiety.


Subject(s)
Chlorogenic Acid/chemistry , Ferric Compounds/chemistry , Quercetin/chemistry , Soybean Oil/chemistry , Hot Temperature , Ions , Oxidation-Reduction
8.
Med Cutan Ibero Lat Am ; 5(6): 443-50, 1977.
Article in Spanish | MEDLINE | ID: mdl-368465

ABSTRACT

In this study we are reviewing the pathology of alcohol and commenting on those dermatological processes most closely related to chronic alcoholism. We adopted the definition of alcoholism as outlined by the WHO (World Health Organization). Also, a general brief description of the woelwide history of alcoholism was included, focusing specially on Argentina with its corresponding legislative study and statistics.


Subject(s)
Alcoholism/complications , Skin Diseases/etiology , Absenteeism , Argentina , Chronic Disease , Humans , Socioeconomic Factors
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