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Recebido em 02/02/2020; aceito em 06/04/2020; publicado na web em 20/05/2020 DETERMINATION OF THE AUTHENTICITY OF COMMERCIAL OLIVE OIL SAMPLES SEIZED IN THE ESPÍRITO SANTO STATE USING A PORTABLE SPECTROPHOTOMETER IN THE NIR REGION. Many instrumental techniques are used to monitor the quality of food products, highlighting near infrared spectroscopy (NIRS).In order to determine the authenticity of 60 commercial oil samples seized by the Espírito Santo state police, this work used a portable spectrometer in the NIR region associated with chemometric tools such as principal component analysis (PCA) and partial least squares regression (PLS) to classify and quantify possible adulterants present such as soybean oil. In addition, physicochemical tests (acidity, peroxide and ultraviolet absorption) were carried out on commercial samples. The PLS regression model built to quantify soybean oil showed a coefficient of determination (R 2 ) greater than 0.99, showing itself to be satisfactory. The results showed that all samples analyzed had a high content of adulterant and cannot be classified as extra virgin olive oil.

The concentrations of lead (Pb), barium (Ba), and antimony (Sb), characteristic of GSR, were determined in soil sediments and immature (larvae) of cadaveric flies of the family Calliphoridae, by inductively coupled plasma mass spectrometry (ICP-MS). This research refers to a case study from two real crime scenes in which the corpses were in an advanced state of decomposition. In case 1, the victim had holes similar to gunshot wounds, and in case 2, there was no evidence of perforations in the corpse. Soil sediment collection was performed at three different points of the terrain, at a minimum distance of 10 m from the corpse, for cases 1 and 2. In relation to the collection of immatures, larvae were collected in regions of the mouth, nose, and orifices similar to the entry of firearms projectile into the body, for case 1, and collection of larvae and pupae, located on the body and underneath it, for case 2. It was possible to detect and quantify the three elements of interest (Pb, Ba, and Sb) by ICP-MS in both sediment and cadaveric larvae. Concentrations of 4.44, 8.74, and 0.08 μg/g were obtained for Pb, Ba, and Sb, respectively, in the soil for case 1. For the case 2, the concentrations in Pb, Ba, and Sb were from 16.34 to 26.02 μg/g; from 32.64 to 57.97 μg/g and from 0.042 to 0.30 μg/g, respectively. In the larvae, Pb, Ba, and Sb were quantified in cases 1 and 2 with a concentration of 6.28 and 1.78 μg/g for Pb, 1.49 and 2.94 μg/g for Ba, 0.50 μg/g and

It has been recurring adulterations in fuels (such as gasoline, ethanol and diesel), being necessary the exploration of the use of more modern analytical techniques capable of controlling the quality of these fuels, since some regulated tests may be inefficient to detect the adulteration. Among them, it is highlighted proton nuclear magnetic resonance (1 H NMR) spectroscopy, and portable near infrared spectroscopy (microNIR). In this work, it was studied the conformities of 115 samples of seized fuels (76 of gasoline, 23 of ethanol, and 16 of diesel) by means of standardized techniques with parameters established by the ANP. Results obtained were compared to photometer, MicroNIR and 1 H NMR analyzes. The analyzes carried out by ANP showed four nonconforming samples (one of gasoline and three of ethanol). By the photometric technique, only 14 gasoline samples had ethanol content permitted by legislation (i.e ≈ 27 %v/v). By 1 H NMR analysis, it was possible to verify nonconformities by presence of aromatics and olefins compounds in the gasoline and diesel samples as well as of methanol in fuel ethanol samples. It is also worth noting the efficiency of MicroNIR when combined with unsupervised chemometric methods to indicate nonconformities presented by 1 H NMR and photometry techniques.