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1.
Meat Sci ; 195: 109012, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36274372

RESUMO

This study evaluated the combination of high-power ultrasound (HPU), micronized salt (MS), and low KCl levels as a strategy to produce reduced sodium Bologna-type sausages. Samples with 50% NaCl reduction were produced with regular salt (RS) or MS and 0.5% KCl. The sausages were sonicated for 0 or 27 min in an ultrasonic bath (25 kHz, 60% amplitude, normal mode, 20 °C) immediately after filling. The sodium reformulation strategy was effective in compensating for the defects in the emulsion stability and texture profile caused by the NaCl reduction. Besides, the combination of HPU, MS, and KCl did not cause major impacts on the evolution of pH, Eh, and TBARS values of the sausages during storage (21 days at 4 °C). The use of MS and KCl also allowed a reduction by 50% of the NaCl content (< 42% Na; Na/K ratio: 1.2 to 1.3) of the samples without affecting the salty taste, which was enhanced by the HPU treatment.


Assuntos
Produtos da Carne , Cloreto de Sódio , Cloreto de Sódio/química , Comportamento do Consumidor , Produtos da Carne/análise , Cloreto de Sódio na Dieta , Sódio , Paladar
2.
Anal Chim Acta ; 1098: 1-26, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31948571

RESUMO

The daily use of cosmetics may expose consumers to localized skin problems and systemic effects caused by absorption of chemical elements. The requirements for suitable quality control and maximum limits for toxic and potentially toxic elements in cosmetics have attracted the attention of the scientific community and of the official institutions around the world. Maximum limits for chemical elements in some cosmetics have been set, but there are disagreements between them. In the same context, many analytical methods have been proposed in the literature, but several challenges during the sample preparation and determination steps related to the high complexity of cosmetics' matrices composition still remain. It is extremely difficulty to establish suitable methods, free of interference, even using modern technology. In this review, methods for determining toxic and potentially toxic elements in cosmetics used for make-up on the lips and on the eye area, covering the period since 2000, are presented. Techniques enabling direct analysis and those requiring a sample preparation step prior to the analysis are also discussed. This review focused on cosmetics for make-up on the lips and on the eye area because the risks of percutaneous absorption and oral ingestion of toxic and potentially toxic elements is higher than in other body regions.


Assuntos
Cosméticos/efeitos adversos , Cosméticos/análise , Cosméticos/toxicidade , Humanos
3.
Rapid Commun Mass Spectrom ; 34 Suppl 3: e8675, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31770460

RESUMO

RATIONALE: Bromine and iodine have important physiological functions; however, in inadequate concentration, they can also cause several physiological problems. Their mobility assessment in human organisms through biological sampling may help clarify some doubts related to metabolic routes, which are still not well elucidated. In this context, a suitable analytical method for this purpose should be developed. METHODS: An analytical method for determining ultratrace levels of bromine and iodine in human nail samples was developed. Inductively coupled plasma mass spectrometry (ICP-MS) using a conventional nebulization system was immediately chosen as the determination tool because of its powerful sensitivity and selectivity. Sample preparation methods including microwave-induced combustion (MIC), microwave-assisted extraction, and microwave-assisted digestion were evaluated. The compatibility of the final solutions with ICP-MS analysis was considered while the method was developed. RESULTS: MIC was chosen as the most suitable method for the sample preparation for determining the levels of bromine and iodine in human nail samples using ICP-MS. Unlike other sample preparation methods, this one fully eliminated interferences related to the carbon content and memory effects. Sample masses up to 100 mg were efficiently digested, and the analytes were quantitatively absorbed using only 50 mmol L-1 NH4 OH solution. Recoveries ranged from 93% to 102%, and the relative standard deviation was < 8%. CONCLUSIONS: The proposed analytical method presents important characteristics for routine analysis. It allows ultratrace determination even when low sample masses are used because of the low blank values, reduced volume of reagents, and powerful detectability using ICP-MS.


Assuntos
Bromo/análise , Iodo/análise , Espectrometria de Massas/métodos , Unhas/química , Bromo/isolamento & purificação , Estudos de Viabilidade , Humanos , Iodo/isolamento & purificação , Limite de Detecção , Micro-Ondas
4.
Anal Chim Acta ; 1060: 45-52, 2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-30902330

RESUMO

An effective analytical method for bromine and iodine determination in human hair using interference-free inductively coupled plasma mass spectrometry (ICP-MS) was developed. Human hair was digested based on combustion reaction to obtain compatible solutions with ICP-MS analysis. Using microwave-induced combustion (MIC), masses of human hair ranging from 50 to 300 mg were efficiently digested. Only a diluted alkaline solution (100 mmol L-1 NH4OH) was used for the absorption of both analytes, which was fully compatible with ICP-MS analysis. Using these conditions low limits of detection were obtained (LOD of 0.01 µg g-1 for Br and 0.004 µg g-1 for I). Recovery tests at two levels (50% and 100%) using a standard solution or mixtures of the sample with certified reference materials (CRMs) were carried out to evaluate the suitability of proposed method and recoveries between 94% and 102% were always obtained. Accuracy was evaluated by analysis of a human hair CRM, and the Br and I concentrations obtained by the proposed method did not differ significantly from those described in the certificate. Repeatability (RSDs ≤ 4%) and reproducibility (RSDs ≤ 7%) of the results using proposed method were always very suitable. The digests obtained using the MIC method were fully compatible with ICP-MS and the interferences currently found using conventional digestion methods were completely eliminated. Ultra-trace concentrations of Br and I were determined in human hair, demonstrating that the proposed method is a suitable strategy, and it presents several advantages compared to others published in the literature.


Assuntos
Bromo/análise , Cabelo/química , Iodo/análise , Humanos , Espectrometria de Massas , Micro-Ondas
5.
Talanta ; 191: 415-421, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30262078

RESUMO

In this work, an analytical method for bromine and iodine determination in human saliva was proposed. A simple protocol based on centrifugation and direct analysis of supernatant by inductively coupled plasma mass spectrometry (ICP-MS) was investigated. Although this method was feasible for bromine determination, iodine was partially present in the supernatant and an agreement about 54% with reference value was obtained. In addition, microwave-induced combustion (MIC) and microwave-assisted dissolution were also evaluated. Using MIC, 0.2 mL of saliva added on 300 mg of microcrystalline cellulose were efficiently digested. A diluted solution (50 mmol L-1 NH4OH) was used for analytes absorption, and a reflux step of 5 min was applied to ensure quantitative recoveries of Br and I. Accuracy was evaluated by analyte recovery experiments, and recoveries between 94% and 98% were obtained. Microwave-assisted dissolution was evaluated for 2.0 mL of saliva using also a diluted alkaline solution (25 mmol L-1 NH4OH) and a microwave irradiation program of 35 min (including the cooling step). Results for this method agreed with those obtained using MIC. Although MIC has also been appropriated for further determination of Br and I in saliva, microwave-assisted dissolution can be considered a simpler sample preparation method and it was effective for high amount of sample (up to 2.0 mL). Moreover, final solutions were compatible with ICP-MS analysis, allowing the quantification of Br and I in human saliva at ultra-trace concentrations (limits of quantification were 0.052 µg mL-1 for Br and 0.022 µg mL-1 for I).


Assuntos
Bromo/análise , Testes de Química Clínica/métodos , Iodo/análise , Saliva/química , Bromo/química , Humanos , Iodo/química , Espectrometria de Massas , Micro-Ondas
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