Spectrophotometry and chromatography analyses combined with chemometrics tools to differentiate green coffee beans into special or traditional.

Green coffee is the hulled coffee bean, rich in chemical compounds indicative of quality before roasting, making the classification special or traditional. This work aimed to determine compounds in green coffee beans and find the differentiation of green coffee beans into special or traditional ones through chemometrics. For that, the levels of phenolic compounds, reducing, nonreducing, and total sugars were quantified by spectrophotometry: caffeine, trigonelline, 5-hydroxymethylfurfural (5-HMF), 3-hydroxybenzoic, 4-hydroxybenzoic, chlorogenic, caffeic, and nicotinic acids (NAs) by high-performance liquid chromatography-UV-Vis; acetaldehyde, acetone, methanol, ethanol, and isoamyl by HS-GC-FID.

Environmentally friendly and novel solid-liquid phase microextraction of maneb fungicide in fruits and vegetables.

The dithiocarbamates class has been widely used in agriculture practices because of lower toxicity and instability than organophosphates and carbamates. Among them, the maneb has been used to produce several fruits and vegetables, but its high ingestion can adversely affect human health. This work developed the Solid-Liquid Phase Microextraction (SLPME) for extraction of the maneb in foods sample with posterior determination by Flow injection analysis-Flame Absorption Atomic Spectroscopy (FIA-FAAS).

Effect of drying methods on nutritional constitutes of fermented grape residue.

One of the biggest hurdles faced by the wine industry is the disposal of residual biomass generated after vinification. Although this residue is biodegradable, it constitutes a potential source of environmental pollutants. To alleviate this issue, this biomass may be used in alternative applications; for example, it may be transformed into an enriched flour that can be used to improve the nutrient content in different foods.

The role of 5-hydroxymethylfurfural in food and recent advances in analytical methods.

The thermal processing, storage, and transportation of foodstuffs (e.g., fruit juices, coffee, honey, and vinegar) generate 5-hydroxymethylfurfural (HMF).

Preconcentration of sulphonamides in bovine milk by the cloud point extraction method using smartphone-based digital images.

Sulphonamides are a group of synthetic antibiotics used specially in veterinary medicine. Among the procedures employed in the sample preparation for sulphonamide determination are liquid-liquid extraction (LLE) and solid-phase extraction (SPE) that use large volumes of organic solvents. Hence, a clean procedure was developed based on preconcentration and cloud point extraction (CPE) without using organic solvents to quantify total sulphonamides in bovine milk.

Current overview and perspectives in environmentally friendly microextractions of carbamates and dithiocarbamates.

Carbamates and dithiocarbamates are two classes of pesticides widely employed in the agriculture practice to control and avoid pests and weeds, hence, the monitoring of the residue of those pesticides in different foodstuff samples is important. Thus, this review presents the classification, chemical structure, use, and toxicology of them. Moreover, it was shown the evolution of liquid- and solid-phase microextractions employed in the extraction of carbamates and dithiocarbamates in water and foodstuff samples.

Use of non-volatile compounds for the classification of specialty and traditional Brazilian coffees using principal component analysis.

Coffee beans contain different volatile and non-volatile compounds that are responsible for their flavor and aroma. Herein, principal component analysis (PCA) was employed to correlate the non-volatile composition of specialty and traditional coffees with drink quality. The quantified non-volatile compounds included caffeine, chlorogenic acid, caffeic acid, and nicotinic acid in both types of coffee samples, while 5-hydroxymethylfurfural was only quantified in the specialty coffee samples.

A spot test for total esters determination in sugarcane spirits exploiting smartphone-based digital images.

Cachaça is an alcoholic beverage produced from sugarcane, whose flavor and taste are related to the esters content, usually expressed as equivalent to ethyl acetate. The official method for the determination of specific esters in cachaça is based on gas chromatography with a flame ionization detector, whereas a volumetric procedure is recommended for determining the total content. Because of the high analytical demand, faster and more practical analytical procedures are required for quality control of the product.

An overview of the Brazilian contributions to Green Analytical Chemistry.

Green Analytical Chemistry (GAC) is a research field that seeks for more sustainable analytical approaches to minimize the toxicity and amounts of wastes without hindering the analytical performance. This is a trend in Analytical Chemistry worldwide and because of the diversity of innovations on this subject, Brazil stands out as the third in the list of the main contributors to GAC, with ca. 11.

Solid-phase extractions in flow analysis.

Coupling solid-phase extraction (SPE) to flow systems has promoted a synergistic development. Whereas SPE mechanization leads to improved precision and higher sample throughput, as well as diminishes systematic errors and contamination risks, analyte concentration and separation from the sample matrix provides a remarkable impact on detectability and selectivity in flow analysis. Historical aspects, main cornerstones, tips for system design, and recent applications are critically reviewed, in the context of analyte(s) separation/concentration, sample clean-up, and release of sorbed chemical species involving both packed (e.

Fluidized particles in flow analysis: potentialities, limitations and applications.

In flow analysis, solid particles (sorbents, reagents or catalysts) have been used for e.g. analyte separation/concentration, sample clean-up, speciation analysis, enzymatic assays, analysis relying on slight soluble reagents, and kinetics studies related to adsorption/release of species.

A flow-based procedure exploiting the lab-in-syringe approach for the determination of ester content in biodiesel and diesel/biodiesel blends.

The ester content is an important parameter to be monitored in biodiesel for evaluation of the transesterification reaction yield and for assessing the purity of the final product. This is also a relevant quality parameter in diesel/biodiesel blends to avoid frauds, because legislation establishes a minimum amount of biodiesel to be added to diesel. The official method EN14103 requires the addition of an alternative internal standard (methyl nonadecanoate) for analysis of biodiesel from bovine tallow because the methyl heptadecanoate is found in high amounts in this product.

A sensitive flow-based procedure for spectrophotometric speciation analysis of inorganic bromine in waters.

A flow-based system with solenoid micro-pumps and long path-length spectrophotometry for bromate and bromide determination in drinking water is proposed. The method is based on the formation of an unstable dye from the reaction between bromate, 2-(5-dibromo-2-pyridylazo)-5-(diethylamino)phenol (5-Br-PADAP) and thiocyanate ions. A multivariate optimization was carried out.

Green chemistry and the evolution of flow analysis. A review.

Flow analysis has achieved its majority as a well-established tool to solve analytical problems. Evolution of flow-based approaches has been analyzed by diverse points of view, including historical aspects, the commutation concept and the impact on analytical methodologies. In this overview, the evolution of flow analysis towards green analytical chemistry is demonstrated by comparing classical procedures implemented with different flow approaches.

Versatile microanalytical system with porous polypropylene capillary membrane for calibration gas generation and trace gaseous pollutants sampling applied to the analysis of formaldehyde, formic acid, acetic acid and ammonia in outdoor air.

The analytical determination of atmospheric pollutants still presents challenges due to the low-level concentrations (frequently in the μg m(-3) range) and their variations with sampling site and time. In this work, a capillary membrane diffusion scrubber (CMDS) was scaled down to match with capillary electrophoresis (CE), a quick separation technique that requires nothing more than some nanoliters of sample and, when combined with capacitively coupled contactless conductometric detection (C(4)D), is particularly favorable for ionic species that do not absorb in the UV-vis region, like the target analytes formaldehyde, formic acid, acetic acid and ammonium. The CMDS was coaxially assembled inside a PTFE tube and fed with acceptor phase (deionized water for species with a high Henry's constant such as formaldehyde and carboxylic acids, or acidic solution for ammonia sampling with equilibrium displacement to the non-volatile ammonium ion) at a low flow rate (8.

A greener and highly sensitive flow-based procedure for carbaryl determination exploiting long pathlength spectrophotometry and photochemical waste degradation.

An environmentally friendly analytical procedure with high sensitivity for determination of carbaryl pesticide in natural waters was developed. The flow system was designed with solenoid micro-pumps in order to improve mixing conditions and minimize reagent consumption as well as waste generation. A long pathlength (100 cm) flow cell based on a liquid core waveguide (LCW) was employed to increase the sensitivity in detection of the indophenol formed from the reaction between carbaryl and p-aminophenol (PAP).

A green analytical procedure for flow-injection determination of nitrate in natural waters.

Nitrate determination in waters is generally carried out with cadmium filings and carcinogenic reagents or by reaction with phenolic compounds in highly concentrated sulfuric acid medium. In this work, it was developed a green analytical procedure for nitrate determination in natural waters based on direct spectrophotometric measurements in ultraviolet, using a flow-injection system with an anion-exchange column for separation of nitrate from interfering species. The proposed method employs only one reagent (HClO(4)) in a minimum amount (equivalent to 18muL concentrated acid per determination), and allowed nitrate determination within 0.

An improved procedure for flow-based turbidimetric sulphate determination based on a liquid core waveguide and pulsed flows.

An improved flow-based procedure is proposed for turbidimetric sulphate determination in waters. The flow system was designed with solenoid micro-pumps in order to improve mixing conditions and minimize reagent consumption as well as waste generation. Stable baselines were observed in view of the pulsed flow characteristic of the systems designed with solenoid micro-pumps, thus making the use of washing solutions unnecessary.