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•Food additives show technological, biological and sensorial functions.•Twenty-five classes of foods additives and their industrial functions are reported.•Detection of food additives ...by spectroscopy, chromatography and electroanalysis.•Analytical techniques used in the studies of food additives.•Perspectives in food additives analysis by analytical techniques are provided.
This work describes the 25 classes of food additives that contain about 230 compounds with technological, sensorial and/or microbiological functionalities. These compounds are added to foods at the processing, packaging and transport steps, to improve the standard of quality, durability and stability of the product and adjust the colour, smell and flavour attributes. Food industries need to follow national and international quality standards that establish the conditions under which food additives may be used, and the food safety is guaranteed by strict quality control. This review describes the analytical techniques used in identification and quantification of food additives in foodstuffs, highlighting the main characteristics of each method (spectroscopy, chromatography and electroanalysis), and indicating the advantages and disadvantages typical of the methods used. Perspectives of the chemical analysis in the food industries are also discussed.
The ubiquitous presence of microplastics in the aquatic environment has raised concern about their potential impacts on and risks to the biota. While the presence of microplastics in a marine ...environment has been well studied, the impact of microplastic contamination in freshwater bodies is understudied. In the present study, baseline data about contamination with microplastics in Lake Guaíba in southern Brazil are presented. The abundance, distribution, and composition of microplastics in the surface of this freshwater body were investigated, and these parameters were correlated with population density, land occupation, wind, and geohydrologic processes. The samples were collected with a manta net (60 μm mesh size). Microplastics were found in all the samples, with an average of 11.9 ± 0.6 to 61.2 ± 6.1 items m−3, which indicates the widespread contamination of the lake with plastic particles. The most frequent microplastic morphology was the fragment type in the size range of 100 to 250 μm, and the predominant colours were white/transparent and red. Measurement uncertainty of the visual microplastic counts showed that black colour microplastics is more susceptible to be mistaken, which might lead to an underestimation and/or overestimation of the total number of microplastics. Polypropylene and polyethylene together comprised most of the polymer types (98%). Micro-Fourier transform infrared (micro-FTIR) spectroscopy analyses showed that 58% of the analysed polymers were highly oxidised, indicating long residence of this particles in the water. In addition, our data show that the distribution of microplastics is strongly influenced by the geohydrological characteristics of the lake. Therefore, this research may provide information for further investigations of microplastic distribution in Lake Guaíba and can serve as a base to improve the regulations regarding waste management to effectively reduce microplastic pollution in freshwater systems. Additionally, the measurement uncertainty showed that black microplastics are more susceptible to variations in their measurements.
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•Geohydrological characteristics influenced the abundance of microplastics.•The dominant microplastics were polyethylene and polypropylene fragments.•Most microplastics found in the lake were highly oxidised.
Abstract
The reaction between He
+
and CO forming He + C
+
+ O has been studied at collision energies in the range between 0 and
k
B
⋅ 25 K. These low collision energies are reached by measuring the ...reaction within the orbit of a Rydberg electron after merging a beam of He(
n
) Rydberg atoms and a supersonic beam of CO molecules with a rotational temperature of 6.5 K. The capture rate of the reaction drops by about 30% at collision energies below
k
B
⋅ 5 K. This behavior is analyzed in terms of the long-range charge–dipole and charge–quadrupole interactions using an adiabatic-channel capture model. Although the charge–dipole interaction has an effect on the magnitude of the rate coefficients, the effects of the charge–quadrupole interaction determine the main trend of the collision-energy dependence of the rate coefficients at low collision energies. The drop of the capture rate coefficient at low collision energies is attributed to the negative sign of the quadrupole moment of CO (
Q
zz
= −2.839 D Å) and is caused by the |
JM
⟩ = |00⟩ and |1 ± 1⟩ rotational states of CO, which represent about 70% of the CO molecules at the rotational temperature of 6.5 K.
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•Indirect determination of the maneb using FIA-FAAS.•Microextraction of the maneb in the foodstuffs without organic solvent.•Factorial designs optimization of the extraction provided ...efficient extractions.•Easy SLPME for extraction of the maneb from foodstuffs samples.
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). Curve analytical had a linear range from 0.9 to 20.0 µmol L−1 maneb (A = 5.94 × 10−4 C (µmol L−1) + 6.93 × 10−4), good repeatability (4.07%) and reproducibility (3.39%), limits of quantification (5.98 µmol L−1) and detection (0.197 µmol L−1), which was above of the established by regulatory agencies. The extraction of the maneb was performed using 685 µL of the solution of the 1.00 × 10−3 mol L−1 of EDTA, and it has excellent recovery values from 80.85 to 106.51%. Therefore, the developed SLPME demonstrated an alternative environmentally friendly for quickly extracting maneb from food samples (apple, papaya, and tomato).
Este artigo baseia-se em algumas questões que levam a repensar os debates da ‘criminologia feminista’ no Brasil e propor formulações criativas para pensar outras formas de enfrentamento da violência ...de gênero, incluindo movimentos sociais compartilhados que utilizam recursos tecnológicos como estratégias de resistência. Propõe-se o uso de hashtags como ferramentas feministas de análise para compreender os fenômenos da violência localizada. Para tanto, serão utilizadas as hashtags #meuprimeiroassedio, #chegadefiufiu e #meuamigosecreto para analisar novos significados de justiça promovidos pelos movimentos feministas, que aparentemente não priorizam o uso do poder punitivo. Da mesma forma, busca-se, por meio do movimento #EleNão, reconhecido como tecnopolítica democrática feminista, reformular as possibilidades de analisar o campo criminológico e enfrentar a violência de gênero a partir de uma perspectiva micro e macropolítica.
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•HMF is a quality marker in food.•It is formed in the Maillard reaction and caramelization process.•HMF indicates food non-conformities and processing efficiency.•Novel spectrometric, ...chromatographic, and electroanalytical methods for HMF determination are critically discussed.
The thermal processing, storage, and transportation of foodstuffs (e.g., fruit juices, coffee, honey, and vinegar) generate 5-hydroxymethylfurfural (HMF). The food industry uses this compound as a quality marker, thus increasing the demand for fast and reliable analytical methods for its determination. This review focuses on the formation of HMF in food, its desirable and toxic effects, and recent advances in analytical methods for its determination in foodstuffs. The advantages and limitations of these analytical approaches are discussed relative to the main analytical features.
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