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1.
Artigo em Inglês | MEDLINE | ID: mdl-36608113

RESUMO

The goal of this work was to investigate the impact of refining on coconut oil particularly on the most toxicologically relevant fraction of the mineral oil aromatic hydrocarbon (MOAH) contamination, namely the fraction composed by the three to seven aromatic rings. A fully integrated platform consisting of a liquid chromatography (LC), a comprehensive multidimensional gas chromatography (GC) (LC-GC × GC) and flame ionization detector (FID) was used to obtained a more detailed characterization of the MOAH sub-classes distribution. The revised EN pr 16995:2017-08 official method was used for preparing the samples, both with and without the auxiliary epoxidation step. Crude coconut oil was spiked with different MOAH standards, namely naphthalenes, alkylated naphthalenes, benzo(a)pyrene, and its alkylated homologues. Refining was modelled by deodorization at 230 °C, stripping with 10 kg/h of steam under 1 mbar vacuum for 3 h. Complete removal of the naphthalenes and reduction of more than 98.8% of the benzo(a)pyrenes was observed. Epoxidation had a significant impact on the MOAH fraction with more than three rings, but with a high dependency on the sample matrix, being significantly less evident in the refined samples than in the crude ones.


Assuntos
Hidrocarbonetos Aromáticos , Petróleo , Óleo Mineral/análise , Óleo de Coco/análise , Contaminação de Alimentos/análise , Hidrocarbonetos Aromáticos/análise , Cromatografia Gasosa/métodos , Petróleo/análise
2.
Artigo em Inglês | MEDLINE | ID: mdl-32693705

RESUMO

Processing Factors (PFs) reflect the concentration or dilution of pesticide residues resulting from food processing. PFs are key elements to demonstrate the compliance of processed foods with Maximum residue levels (MRLs) as set by Regulation 396/2005. While efforts have been made by the European Food Safety Authority (EFSA) and by national authorities to compile PFs from processing studies, such PFs are not available for all pesticides/processed product combinations. The EU vegetable oil and proteinmeal industry association (FEDIOL) has therefore developed a theoretical approach to approximate MRLs in crude vegetable oils and fats, based on the partition coefficient (log Pow) of the pesticides and on the oil content of the raw materials. To substantiate this approach, a pilot-scale processing study was initiated with rapeseeds spiked with selected pesticides and the experimental PFs for these pesticides determined. The aims of this study were (i) to study the reliability of pilot-scale conditions for PF determination and (ii) to assess the experimental PFs obtained in comparison to the theoretical PFs proposed by FEDIOL. This study demonstrated that production yields obtained for crude oil and meal in this processing study are similar to those in industrial processes even if differences were observed in the individual production steps (mechanical or solvent extraction steps). The experimental PFs obtained confirmed that the chosen fat-soluble pesticides did concentrate in the oil fraction. For metalaxyl-M having a log Pow lower than 3, a partitioning between the oil and the meal was observed, as expected. By comparing the experimental PFs and theoretical PFs, it can be concluded that the FEDIOL approach can be recommended as a suitable tool when PFs derived from specific processing studies are missing. Similar studies on pesticides with wider ranges of log Pow are required in order to complete our conclusions on default PFs for vegetable oils.


Assuntos
Contaminação de Alimentos/análise , Manipulação de Alimentos , Praguicidas/análise , Óleos de Plantas/química , Sementes/química
3.
Am J Clin Nutr ; 91(5): 1220-6, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20335546

RESUMO

BACKGROUND: The modern Western lifestyle is characterized by the consumption of high-heat-treated foods because of their characteristic taste and flavor. However, it has been shown that treating food at high temperatures can generate potentially harmful compounds that promote inflammation and cardiovascular disease in subjects with diabetes. OBJECTIVE: The aim of this study was to determine whether high-heat-treated foods also pose a risk for healthy subjects. DESIGN: A randomized, crossover, diet-controlled intervention trial with 62 volunteers was designed to compare the potential metabolic effects of 2 diets, one that was based on mild steam cooking and another that was based on high-temperature cooking. These 2 diets differed mainly in their contents of Maillard reaction products (MRPs). MRPs were assessed in the diet and in subjects' feces, blood, and urine samples, with N(epsilon)-carboxymethyllysine as an indicator of MRPs. Biological indicators of glucose and lipid metabolism as well as oxidative stress were analyzed in subjects after 1 mo on each diet. RESULTS: In comparison with the steamed diet, 1 mo of consuming the high-heat-treated diet induced significantly lower insulin sensitivity and plasma concentrations of long-chain n-3 (omega-3) fatty acids and vitamins C and E [-17% (P < 0.002), -13% (P < 0.0001), and -8% (P < 0.01), respectively]. However, concentrations of plasma cholesterol and triglycerides increased [+5% (P < 0.01) and +9% (P < 0.01), respectively]. CONCLUSIONS: A diet that is based on high-heat-treated foods increases markers associated with an enhanced risk of type 2 diabetes and cardiovascular diseases in healthy people. Replacing high-heat-treatment techniques by mild cooking techniques may help to positively modulate biomarkers associated with an increased risk of diabetes mellitus and cardiovascular diseases.


Assuntos
Doenças Cardiovasculares/epidemiologia , Culinária , Diabetes Mellitus Tipo 2/epidemiologia , Temperatura Alta/efeitos adversos , Ácido Ascórbico/sangue , Índice de Massa Corporal , Doenças Cardiovasculares/etiologia , Colesterol/sangue , Estudos Cross-Over , Diabetes Mellitus Tipo 2/etiologia , Ácidos Graxos Ômega-3/sangue , Feminino , Humanos , Inflamação/etiologia , Insulina/fisiologia , Estilo de Vida , Reação de Maillard , Masculino , Fatores de Risco , Triglicerídeos/sangue , Vitamina E/sangue , Adulto Jovem
4.
J Agric Food Chem ; 56(15): 6241-5, 2008 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-18616270

RESUMO

A new sensitive and selective method has been developed for the quantification of the total coenzyme Q9 (CoQ9) and coenzyme Q10 (CoQ10) concentration in vegetable oil samples. The coenzyme Q fraction is isolated by solid-phase extraction (SPE) on amino phase eluting with a mixture of heptane:ethyl ether. The organic solvent is evaporated under nitrogen, and the residue is dissolved in a mixture of acetonitrile:tetrahydrofuran and finally is analyzed by reverse-phase high-performance liquid chromatography with a mass detector. The sensitivity of the method is based on the high efficient formation of the radical anions [M (-.)] of CoQ9 and CoQ10 by negative atmospheric pressure ionization. Interferences are minimized by using mass detection of the [M (-.)] ions ( m/ z = 797.5 for CoQ9 and m/ z = 862.5 for CoQ10) in selective reaction monitoring mode ( m/ z = 797.5 --> m/ z = 779.5 and m/ z = 862.5 --> m/ z = 847.5) using a triple-quadrupole mass spectrometer. The method was successfully applied to sunflower, soybean, and rapeseed oils, with a limit of quantification of 0.025 mg/kg for both compounds.


Assuntos
Óleos de Plantas/química , Ubiquinona/análogos & derivados , Cromatografia Líquida de Alta Pressão , Ácidos Graxos Monoinsaturados , Óleo de Brassica napus , Sensibilidade e Especificidade , Solventes , Óleo de Soja/química , Óleo de Girassol , Ubiquinona/análise
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