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1.
J Agric Food Chem ; 68(8): 2562-2569, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32003990

RESUMO

This study was aimed to evaluate the level of furan and acrylamide contamination in cocoa and noncocoa raw materials, in masses from processing stages, and in chocolates originating from three factories. Acrylamide was determined by the gas chromatography-mass spectrometry (GC-MS) method using the QuEChERS procedure with dispersive solid-phase extraction clean-up and isotopic standard (2,3,3-d3-acrylamide). Furan was analyzed by the headspace solid-phase microextraction/GC-MS technique with the d4-furan marker. Both analytical methods were validated in terms of accuracy, precision, and linearity as well as the limit of detection (LOD) and limit of quantification (LOQ). Among all raw materials, the most abundant in acrylamide were cocoa masses and powders (83.0-127.5 ng g-1). Roasting of cocoa beans increased the content of acrylamide 2-3-fold. The obtained results indicate that acrylamide might be formed during wet conching. Only in cocoa powders and lecithin, it was possible to quantify furan (3.7-10.2 and 16.3 ng g-1, respectively). Roasting of cocoa beans increased the content of furan from

Assuntos
Acrilamida/análise , Cacau/química , Chocolate/análise , Furanos/análise , Acrilamida/isolamento & purificação , Contaminação de Alimentos/análise , Manipulação de Alimentos , Furanos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Sementes/química , Microextração em Fase Sólida
2.
Meat Sci ; 121: 292-301, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27395822

RESUMO

Raw pork neck cutlets were marinated in an aqueous solution of acetic acid (pH4, 24h, 4°C) without (M) or with 1% (w/w) of glucose. The control (K) was formed by non-treated raw pork neck. The cutlets were then broiled (185°C, 30min). In all K cutlets, significant higher amounts of volatile compounds (VCs) were developed after broiling than the other samples. Significant more aldehydes and alcohols were present in the inner parts than in the surface. The correlation between surface and internal layers was high only for aldehydes. Marinating decreased the differences among VCs and led to the standardization of the processed meat. The addition of glucose to the marinade led to more volatile aldehydes, carboxylic acids, esters, furan, pyran, pyrazine, pyrrol and pyridine derivatives than in M samples. Several (53) specific VCs explained the differences among the surface samples related to the marinating process. However, only 16 VCs explained the variance among the inner parts.


Assuntos
Ácido Acético/análise , Manipulação de Alimentos , Carne Vermelha/análise , Compostos Orgânicos Voláteis/análise , Álcoois/análise , Aldeídos/análise , Animais , Furanos/análise , Piranos/análise , Pirazinas/análise , Piridinas/análise , Suínos
4.
Lipids ; 50(4): 359-70, 2015 04.
Artigo em Inglês | MEDLINE | ID: mdl-25739731

RESUMO

Isoprenoid alcohols are common constituents of living cells. They are usually assigned a role in the adaptation of the cell to environmental stimuli, and this process might give rise to their oxidation by reactive oxygen species. Moreover, cellular isoprenoids may also undergo various chemical modifications resulting from the physico-chemical treatment of the tissues, e.g., heating during food processing. Susceptibility of isoprenoid alcohols to heat treatment has not been studied in detail so far. In this study, isoprenoid alcohols differing in the number of isoprene units and geometry of the double bonds, ß-citronellol, geraniol, nerol, farnesol, solanesol and Pren-9, were subjected to thermo-oxidation at 80 °C. Thermo-oxidation resulted in the decomposition of the tested short-chain isoprenoids as well as medium-chain polyprenols with simultaneous formation of oxidized derivatives, such as hydroperoxides, monoepoxides, diepoxides and aldehydes, and possible formation of oligomeric derivatives. Oxidation products were monitored by GC-FID, GC-MS, ESI-MS and spectrophotometric methods. Interestingly, nerol, a short-chain isoprenoid with a double bond in the cis (Z) configuration, was more oxidatively stable than its trans (E) isomer, geraniol. However, the opposite effect was observed for medium-chain polyprenols, since Pren-9 (di-trans-poly-cis-prenol) was more susceptible to thermo-oxidation than its all-trans isomer, solanesol. Taken together, these results experimentally confirm that both short- and long-chain polyisoprenoid alcohols are prone to thermo-oxidation.


Assuntos
Álcoois/química , Pentanóis/química , Terpenos/química , Monoterpenos Acíclicos , Hemiterpenos , Temperatura Alta , Oxirredução , Estereoisomerismo
5.
Artigo em Inglês | MEDLINE | ID: mdl-25654207

RESUMO

Because several groups of microorganisms are able to decarboxylate amino acids, the presence of biogenic amines (BA) can be seen as an index of the microbiological quality of the brewing process. BAs were quantified for the first time in the intermediate products and craft beers produced with malted organic Emmer wheat (Triticum dicoccum) in a small size brewery in order to assess the possible presence of critical control points related to biological hazard in the brewing process. BA levels in beers produced exclusively from malted organic Emmer wheat were between 15.4 and 25.2 mg l(-1) in the samples of light beer (Lt) and between 8.9 and 15.3 mg l(-1) in double malt beers (DM) ready for consumption (the beers stored for 90 days at 1-2°C). Cadaverine and tyramine were the main BAs in the Lt and DM beers, respectively. Increased concentrations of BAs seemed to be more related to the heat treatment of the processing product during mashing and wort boiling, rather than to the fermentation process. Much lower concentrations were found in finished beers obtained from 50% malted organic Emmer wheat and 50% malted barley (up to 3.2 mg l(-1)) or from 30% malted Emmer wheat (up to 8.3 mg l(-1)). Thus, Emmer wheat malt can be a useful alternative to wheat and spelt for the production of beer with a limited content of BA, if the processing technology is kept under control.


Assuntos
Cerveja/análise , Aminas Biogênicas/análise , Alimentos Orgânicos , Triticum , Cadaverina/análise , Cromatografia Líquida de Alta Pressão , Fermentação , Análise de Alimentos , Contaminação de Alimentos/análise , Manipulação de Alimentos , Análise de Perigos e Pontos Críticos de Controle/métodos , Hordeum , Modelos Lineares , Tiramina/análise
6.
J Agric Food Chem ; 62(42): 10341-7, 2014 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-25265293

RESUMO

The aim of the present work was to assess the influence of the baking process on the fumonisin content in gluten-free bread. The dough was made using two methods: without sourdough and with sourdough. Fumonisins were determined using high-performance liquid chromatography with ion-trap mass spectrometry. This study showed that the bread baking process caused a statistically significant drop in the mean concentration of free fumonisins: the reduction levels were 30 and 32% for the direct and sourdough-based methods, respectively. The lower reduction after baking was observed for hidden fumonisins: 19 and 10%, respectively. The presence of some compounds (such as proteins or starch) capable of stabilizing fumonisins during the baking process might be responsible for the observed increase in the hidden-to-free ratio from an initial 0.72 in flour to 0.83 in bread made from sourdough and to 0.95 in sourdough-free bread.


Assuntos
Pão/análise , Culinária/métodos , Fumonisinas/análise , Glutens/análise , Contaminação de Alimentos/análise , Temperatura Alta
7.
Acta Sci Pol Technol Aliment ; 13(2): 145-54, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24876310

RESUMO

BACKGROUND: Parsley leaf is a rich source of natural antioxidants, which serve a lot of functions in human body and prevent food from oxidation processes. The aim of the study was to investigate the influence of different extraction solvents and times of extraction on natural antioxidants content. Owing to the knowledge of the properties of extracted components and solvents, as well as their interactions, it is possible to achieve a high effectiveness of active compounds recovery. MATERIAL AND METHODS: Three different extraction solvents (acetone 70% in water, methanol 80% in water and distilled water) and different times of extraction (30 and 60 minutes) were used to determine the efficiency of extraction of polyphenols and catechins, antioxidant activity against free radicals DPPH and ABTS and the ability to chelate ion Fe(2+) in dried parsley leaves. Other natural antioxidants contents in parsley leaves were also determined. RESULTS AND DISCUSSION: In this study the best extraction solvent for polyphenols was acetone 70% and for catechins was distilled water. All extracts examined displayed the antioxidative activity, but water was the best solvent in the method of assaying the activity against ABTS(•+) and Fe(2+) ions chelating capability, whereas methanol turned out to be the least effective in this respect. Opposite results were observed in the case of determining the activity against DPPH(•). The prolongation of the extraction time enhanced or decreased antiradical activity in some cases. Additionally, important biologically active compounds in parsley leaves, such as vitamin C (248.31 mg/100 g dry matter), carotenoids (31.28 mg/100 g dry matter), chlorophyll (0.185 mg/g dry matter) were also analysed.


Assuntos
Técnicas de Química Analítica/métodos , Petroselinum/química , Extratos Vegetais/química , Folhas de Planta/química , Polifenóis/análise , Solventes , Animais , Ácido Ascórbico/análise , Carotenoides/análise , Catequina/análise , Clorofila/análise , Sequestradores de Radicais Livres/análise , Radicais Livres/análise , Polifenóis/isolamento & purificação , Fatores de Tempo
8.
Artigo em Inglês | MEDLINE | ID: mdl-23837439

RESUMO

Fumonisins are mycotoxins produced by the Fusarium group of fungi commonly found on crops, mainly on maize. Some data suggest that as much as 25% of world crops may be lost because of mycotoxin contamination. Therefore, researchers in many countries (particularly in those in which relatively large amounts of maize are directly consumed by humans) are concerned with fumonisin levels in plant-origin foodstuffs and feeds available in their local markets. There is no doubt the levels are strongly correlated with the climate conditions prevailing in the region in which the maize was cultivated: the hotter the climate, the more serious the problem. Negative consequences of consumption of fumonisin-contaminated food by humans include an increased risk of oesophagus cancer and decreased body mass growth. In recent years some trials have been undertaken to reduce fumonisin levels in food and feed by the application of isothiocyanates naturally occurring in plants or peptidoglycans isolated from lactic acid bacteria (LAB). The results of these studies suggested that some reduction in contamination levels might be achieved. Additionally, some recent studies indicate that Sphingopyxis sp. bacteria produce enzymes that are able to break down the fumonisin molecule. Some fumonisins present in food may be bound/coupled with other compounds, and therefore difficult to detect. Such complexes in which the toxins are masked or hidden may even be at higher levels than the not-bound (free) molecules. The problem of how to evaluate effectively and efficiently the concentration of fumonisins in various foodstuffs is therefore a real-life challenge for scientists.


Assuntos
Ração Animal/análise , Carcinógenos Ambientais/análise , Produtos Agrícolas/química , Contaminação de Alimentos , Fumonisinas/análise , Ração Animal/microbiologia , Ração Animal/normas , Criação de Animais Domésticos , Animais , Carcinógenos Ambientais/química , Carcinógenos Ambientais/metabolismo , Produtos Agrícolas/microbiologia , Produtos Agrícolas/normas , Contaminação de Alimentos/legislação & jurisprudência , Contaminação de Alimentos/prevenção & controle , Manipulação de Alimentos , Inspeção de Alimentos/legislação & jurisprudência , Inspeção de Alimentos/métodos , Fumonisinas/química , Fumonisinas/metabolismo , Fusarium/crescimento & desenvolvimento , Fusarium/metabolismo , Saúde Global , Humanos , Legislação sobre Alimentos , Silagem/análise , Silagem/microbiologia , Silagem/normas , Zea mays/química , Zea mays/microbiologia
9.
J Sep Sci ; 36(3): 578-84, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23341269

RESUMO

The aim of this study was to develop an analytical method for qualitative and quantitative determination of the B(1), B(2,) and B(3) fumonisins in cereal products. A LC coupled to an IT-MS was used as the analytical instrument. The AFFINIMIP FumoZON Molecularly Imprinted Polymer SPE cartridges (Polyintell) were used to isolate fumonisins from the analyzed samples and the clean-up step. Statistical parameters evaluated in some validation experiments were as follows: mean recovery 95-106%, precision <17% (expressed as recovery RSD). The developed method was used to determine fumonisins in 49 cereals (42 maize-based and seven wheat-based products). In most cases, concentrations of the studied compounds found in the analyzed samples were low. The highest total concentration of the B(1), B(2), and B(3) fumonisins was found in maize flour samples (range, 26-1102 µg/kg, mean 498 µg/kg).


Assuntos
Grão Comestível/química , Contaminação de Alimentos/análise , Fumonisinas/isolamento & purificação , Polímeros/química , Extração em Fase Sólida/métodos , Fumonisinas/química , Espectrometria de Massas , Impressão Molecular , Polímeros/síntese química , Extração em Fase Sólida/instrumentação
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