An integrative review of analytical techniques used in food authentication: A detailed description for milk and dairy products.

The use of suitable analytical techniques for the detection of adulteration, falsification, deliberate substitution, and mislabeling of foods has great importance in the industrial, scientific, legislative, and public health contexts. This way, this work reports an integrative review with a current analytical approach for food authentication, indicating the main analytical techniques to identify adulteration and perform the traceability of chemical components in processed and non-processed foods, evaluating the authenticity and geographic origin. This work presents results from a systematic search in Science Direct® and Scopus® databases using the keywords "authentication" AND "food", "authentication," AND "beverage", from published papers from 2013 to, 2024. All research and reviews published were employed in the bibliometric analysis, evaluating the advantages and disadvantages of analytical techniques, indicating the perspectives for direct, quick, and simple analysis, guaranteeing the application of quality standards, and ensuring food safety for consumers. Furthermore, this work reports the analysis of natural foods to evaluate the origin (traceability), and industrialized foods to detect adulterations and fraud. A focus on research to detect adulteration in milk and dairy products is presented due to the importance of these products in the nutrition of the world population. All analytical tools discussed have advantages and drawbacks, including sample preparation steps, the need for reference materials, and mathematical treatments. So, the main advances in modern analytical techniques for the identification and quantification of food adulterations, mainly milk and dairy products, were discussed, indicating trends and perspectives on food authentication.

Trends in pulse voltammetric techniques applied to foodstuffs analysis: The food additives detection.

Food additives are chemical compounds intentionally added during foodstuff production to control technological functions, such as pH, viscosity, stability (color, flavor, taste, and odor), homogeneity, and loss of nutritional value. These compounds are fundamental in inhibition the degradation process and prolonging the shelf life of foodstuffs. However, their inadequate employment or overconsumption can adversely affect consumers' health with the development of allergies, hematological, autoimmune, and reproductive disorders, as well as the development of some types of cancer. Thus, the development and application of simple, fast, low-cost, sensitivity, and selectivity analytical methods for identifying and quantifying food additives from various chemical classes and in different foodstuffs are fundamental to quality control and ensuring food safety. This review presents trends in the detection of food additives in foodstuffs using differential pulse voltammetry and square wave voltammetry, the main pulse voltammetric techniques, indicating the advantages, drawbacks, and applicability in food analysis. Are discussed the importance of adequate choices of working electrode materials in the improvements of analytical results, allowing reliable, accurate, and inexpensive voltammetric methods for detecting these compounds in foodstuffs samples.

Is chemical analysis suitable for detecting mycotoxins in agricultural commodities and foodstuffs?

The assessment of the risks of mycotoxins to humans through consuming contaminated foods resulted in specific legislation that evaluates the presence, quantities, and type of mycotoxins in agricultural commodities and foodstuffs. Thus, to ensure compliance with legislation, food safety and consumer health, the development of suitable analytical procedures for identifying and quantifying mycotoxins in the free or modified form, in low-concentration and in complex samples is necessary. This review reports the application of the modern chemical methods of analysis employed in mycotoxin detection in agricultural commodities and foodstuffs. It is reported extraction methods with reasonable accuracy and those present characteristics according to guidelines of Green Analytical Chemistry. Recent trends in mycotoxins detection using analytical techniques are presented and discussed, evaluating the robustness, precision, accuracy, sensitivity, and selectivity in the detection of different classes of mycotoxins. Sensitivity coming from modern chromatographic techniques allows the detection of very low concentrations of mycotoxins in complex samples. However, it is essential the development of more green, fast and more suitable accuracy extraction methods for mycotoxins, which agricultural commodities producers could use. Despite the high number of research reporting the use of chemically modified voltammetric sensors, mycotoxins detection still has limitations due to the low selectivity from similar chemical structures of mycotoxins. Furthermore, spectroscopic techniques are rarely employed due to the limited number of reference standards for calibration procedures.

New approaches in antibiotics detection: The use of square wave voltammetry.

Antibiotics belongs to a class of pharmaceutical compounds widely used due to their effectiveness against bacterial infections. However, if consumed or inappropriately disposed of in the environment can results in environmental and public health problems, because they are considered emerging contaminants and their residues represent damage, whether in the long or short term, to different terrestrial ecosystems, in addition to bringing potential risks to agricultural sectors, such as livestock and fish farming. For this, the development of analytical methods for low-concentration detection and identification of antibiotics in natural waters, wastewaters, soil, foods, and biological fluids is necessary. This review shows the applicability of square wave voltammetry for the analytical determination of antibiotics from different chemical classes and covers a variety of samples and working electrodes that are used as voltammetric sensors. The review involved the analysis of scientific publications from the Science Direct® and Scopus® databases, with scientific manuscripts covering the period between January 2012 and May 2023. Various manuscripts were discussed indicating the applicability of square wave voltammetry in antibiotics detection in urine, blood, natural waters, milk, among other complex samples.

Current electroanalytical approaches in the carbamates and dithiocarbamates determination.

Pesticides are a suitable tool for controlling plagues and disease vectors. However, their inappropriate use allows for contamination of the environment, soil, water, and foods. Carbamates and dithiocarbamates pesticides present accumulative effects in the human body resulting in hormonal, neurological and reproductive disorders, and some are still suspected or proven to give carcinogenic or mutagenic effects. This review provides a current electroanalytical approach in the carbamates and dithiocarbamates determination, showing the use of voltammetric techniques such as amperometry, cyclic and linear scan, differential pulse, and square wave voltammetry, indicating their advantages, disadvantages, and perspectives in electroanalytical detection of carbamates and dithiocarbamates in natural water and foods. Also are reported the different materials used in the preparation of working electrodes since their choice has an important impact on the success of the analytical applications, resulting in suitable sensitivity, selectivity, stability, and robustness.

Detection of Synthetic Antioxidants: What Factors Affect the Efficiency in the Chromatographic Analysis and in the Electrochemical Analysis?

Antioxidants are food additives largely employed to inhibit oxidative reactions in foodstuffs rich in oils and fat lipids, extending the shelf life of foodstuffs and inhibiting alterations in color, flavor, smell, and loss of nutritional value. However, various research has demonstrated that the inadequate use of synthetic antioxidants results in environmental and health problems due to the fact that some of these compounds present toxicity, and their presence in the human body, in high concentrations, is related to the development of some cancer types and other diseases. Therefore, the development of analytical methods for identifying and quantifying synthetic antioxidants in foodstuffs is fundamental to quality control and in ensuring consumer food safety. This review describes the recent chromatographic and electrochemical techniques used in the detection of synthetic phenolic antioxidants in foodstuffs, highlighting the main characteristics, advantages and disadvantages of these methods, and specific typical features, which include extraction methods for sample preparation and materials used in the working electrode construction, considering chromatographic and voltammetric methods, since these specific features influence the efficiency in the analysis.

Antidepressants determination using an electroanalytical approach: A review of methods.

Antidepressants are the pharmaceutical compounds used in the treatment of depression, anxiety disorders and all related disturbances promoted by genetic factors, environmental problems or modern lifestyles. Nonetheless, the inadequate ingestion of antidepressants provokes adverse effects in the human body and can contaminate the environment. For this reason, it is necessary to identify and quantify these compounds in biological fluids, natural water, wastewater, and pharmaceutical formulations. Consequently, this review presents the main electroanalytical techniques used in the analysis of antidepressants, indicating the advantages, which include low cost, suitable analytical parameters, simplified sample preparation steps, easy operation and reduced time for completion of the analysis. Reports in specialized literature, published from 2000 to 2020, are presented and some are discussed, demonstrating that the electroanalytical techniques can be employed, with success, in the determination of antidepressants, indicating alternative methodologies to improve analytical parameters and minimize the use and generation of toxic residues.

Pesticides determination in foods and natural waters using solid amalgam-based electrodes: Challenges and trends.

The intensive use of pesticides in agricultural practices has promoted the appearance of environmental and public health problems. So, there has been a sharp increase in the development of simple, fast, sensitive, selective, and low-cost methods to analyse pesticides. Among them, electroanalytical methods have been frequently employed; however, the performance of these methods is strongly influenced by the working electrode material and so an adequate choice is critical to success of the analysis. Solid amalgam-based electrodes have been widely used; this review critically discusses the evolution of the preparation and use of these electrodes and their application in analysis of pesticides from different chemical classes, indicating challenges and trends in pesticide electroanalysis. The relationship between pesticides' chemical structures and electrochemical behaviour on a mercury-based electrode is explored in order to indicate the use of electroanalysis in pesticide determination.

Analytical methods in food additives determination: Compounds with functional applications.

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.

Polished silver solid amalgam electrode and cationic surfactant as tool in electroanalytical determination of methomyl pesticide.

The polished silver solid amalgam electrode (p-AgSAE) combined with square wave voltammetry (SWV) was used in the development of an analytical procedure to Methomyl determination in natural water samples. The experimental and voltammetric parameters were optimized and the use of cationic surfactant cetyltrimethyl ammonium bromide promoted a considerable change in the kinetic and mechanism of the Methomyl reaction. Was observed the presence one-single reduction peak, related to a totally irreversible two-electrons transfer, followed by chemical reaction involving two protons. Analytical parameters (linearity range, analytical curve equations, correlation coefficient, detection and quantification limits, recovery efficiency, and relative standard deviation for intraday and interday experiments) were evaluated indicating that the proposed voltammetric procedure is suitable for determination of Methomyl. The application of the proposed procedure in natural water analysis indicated high robustness with only simple filtration, without pre-concentration steps, good stability and suitable sensitivity to determination of Methomyl in natural water samples.

A Comparative Electrochemical Behaviour Study and Analytical Detection of the p-Nitrophenol Using Silver Solid Amalgam, Mercury, and Silver Electrodes.

This work reports a comparative electrochemical behaviour study and p-nitrophenol analytical detection using silver solid amalgam, hanging dropping mercury, and silver electrodes. For this, square wave voltammetry was employed, where the analytical responses and the redox mechanisms could be compared for reduction processes of 4-nitrophenol by analysis of the voltammetric responses. The analytical performance of the electrode was evaluated and detection and quantification limits, recovery percentages, repeatability, and reproducibility for the silver solid amalgam and hanging dropping mercury electrodes presented similar values; the results presented for the silver electrode indicated worse analytical parameters than the other electrodes. The results indicate that the silver solid amalgam electrode can be considered a suitable tool and an interesting alternative for the analytical determination of 4-nitrophenol, as well as for the determination of other biological and environmentally interesting compounds that present analytical responses on mercury surfaces.

A simple and sensitive detection of diquat herbicide using a dental amalgam electrode: a comparison using the chromatographic technique.

This paper describes the use of a dental amalgam electrode (DAE) to evaluate the electrochemical behaviour and to develop an electroanalytical procedure for determination of diquat herbicide in natural water and potato samples. The work was based on the square wave voltammetry responses of diquat, which presented two well-defined and reversible reduction peaks, at -0.56 V (peak 1) and -1.00 V (peak 2). The experimental and voltammetric parameters were optimised, and the analytical curves were constructed and compared to similar curves performed by high performance liquid chromatography coupled to ultraviolet-visible spectrophotometric detector (HPLC/UV-vis). The responses were directly proportional to diquat concentration in a large interval of concentration, and the calculated detection limits were very similar, around 10 microg L(-1) (10 ppb) for voltammetric and chromatographic experiments. These values were lower than the maximum residue limit established for natural water by the Brazilian Environmental Agency. The recovery percentages in pure electrolyte, natural water and potato samples showed values from 70% to 130%, demonstrating that the voltammetric methodology proposed is suitable for determining any contamination by diquat in different samples, minimising the toxic residues due to the use of liquid mercury or the adsorptive process relative to use of other solid surfaces.

Voltammetric detection of paraquat pesticide on a phthalocyanine-based pyrolitic graphite electrode.

This work describes the application of an ordinary pyrolitic graphite electrode modified by metallophthalocyanine allied to square wave voltammetry for the study of the electrochemical behavior of the herbicide paraquat and the development of a method for its analytical determination in natural water samples. Preliminary experiments indicated that the best responses, considering the intensities of the current and voltammetric profile for the paraquat reduction process, were obtained when the electrode modified by cobalt phthalocyanine was employed, which had a better catalytic activity as a result of this modification compared with that for an unmodified electrode and electrodes modified by iron, manganese and the acid form of the phthalocyanines. Studies of the concentration of cobalt phthalocyanine and the adsorption time showed that 1.0x10(-4) mol L(-1) cobalt phthalocyanine with an adsorption time of 10 min was sufficient to obtain reliability and stability of modification for employment in the development of the electroanalytical procedure for paraquat determination in natural water samples. The variation in pH of a 0.10 mol L(-1) Britton-Robinson buffer solution and the square wave parameters indicated that the best conditions to reduce paraquat were pH 7.0, a frequency of 100 s(-1), a scan increment of 2 mV and a square wave amplitude of 50 mV. Under such conditions, the variation of paraquat concentrations from 5.00x10(-7) to 2.91x10(-5) mol L(-1) showed a linear relation, with detection and quantification limits of 26.53 and 88.23 microg L(-1); those values were lower than the maximum limits for drinking water permitted by the Brazilian Environmental Council (100 microg L(-1)), indicating that the method could be employed to analyze paraquat in drinking water samples.

Determination of triazine herbicides: development of an electroanalytical method utilizing a solid amalgam electrode that minimizes toxic waste residues, and a comparative study between voltammetric and chromatographic techniques.

The use of a copper solid amalgam electrode (CuSAE) for the analytical determination of triazine herbicides (atrazine and ametryne) instead of the conventional hanging mercury drop electrode (HMDE) is reported. The results obtained using electroanalytical methods utilizing each of these electrodes were also compared with those provided by the HPLC technique. The results indicated that the CuSAE electrode can be used to detect the herbicides studied, since the detection limits reached using the electrode (3.06 microg L-1 and 3.78 microg L-1 for atrazine and ametryne, respectively) are lower than the maximum values permitted by CONAMA (Brazilian National Council for the Environment) for wastewaters (50 microg L-1) and by the US EPA (Environmental Protection Agency of the United States) in natural water samples (10.00 microg L-1). An electroanalytical methodology employing CuSAE and square wave voltammetry (SWV) was successfully applied to the determination of atrazine and ametryne in natural water samples, yielding good recoveries (70.30%-79.40%). This indicates that the CuSAE provides a convenient substitute for the HMDE, particularly since the CuSAE minimizes the toxic waste residues produced by the use of mercury in HDME-based analyses.

Electroanalytical method for determination of the pesticide dichlorvos using gold-disk microelectrodes.

This paper reports the use of laboratory-prepared gold microelectrodes and square-wave voltammetry for analytical determination of low concentrations of the pesticide dichlorvos in pure and natural water samples. After optimization of the experimental and voltammetric conditions, the best voltammetric responses-current intensity and voltammetric profile-were obtained in 0.1 mol L(-1) NaClO4 with f=100 s(-1), a=50 mV, and DeltaE(s)=2 mV. The observed detection and quantification limits in pure water were 7.8 and 26.0 microg L(-1), respectively. The reproducibility and repeatability of the method were also determined; the results were 1.4% (n=5) and 1.2% (n=10), respectively. Possible interfering effects were evaluated in natural water samples collected at different points with different levels of contamination from agricultural, domestic, or industrial waste from an urban stream. Results showed that the detection and quantification limits increased as a function of the quantity of organic matter present in the samples. Nonetheless, the values observed for these method characteristics were below the maximum value allowed by the Brazilian code for organophosphorus pesticides in water samples. Recovery curves constructed using the standard addition method were shown to be satisfactory compared with those obtained from high-performance liquid chromatography, confirming the suitability of the method for analysis of natural water samples. Finally, when the method was used to determine dichlorvos in spiked cows' milk samples, satisfactory recovery and relative standard deviations were obtained.