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1.
Molecules ; 28(10)2023 May 17.
Article in English | MEDLINE | ID: mdl-37241891

ABSTRACT

Food safety is recognized as a main requirement for consumers, food industries, and official laboratories. Here, we present the optimization and screening qualitative validation of two multianalyte methods in bovine muscle tissues by ultra-high-performance liquid chromatography coupled to high-resolution mass spectrometry with an Orbitrap-type analyzer, operated with a heated ionization source in positive and negative mode. This aims for not only the simultaneous detection of veterinary drugs regulated in Brazil but also the prospection of antimicrobials not yet monitored. Two different sample preparation procedures were applied: method A-generic solid-liquid extraction with 0.1% formic acid (v/v) in an aqueous solution of EDTA 0.1% (w/v)-acetonitrile-methanol (1:1:1, v/v/v), followed by an additional ultrasound-assisted extraction and method B-QuEChERS. In both procedures, selectivity showed satisfactory conformity. From a detection capability (CCß) equivalent to ½ the maximum residue limit, >34% of the analyte resulted in a false positive rate of <5%, preponderant by the QuEChERS method, which exhibited a higher yield of the sample. The results showed the potential application of both procedures in the routine analysis of foods by official laboratories, enabling the expansion of this methodological portfolio as well as its analytical scopes, thus optimizing the control of residues of veterinary drugs in the country.


Subject(s)
Veterinary Drugs , Animals , Cattle , Chromatography, High Pressure Liquid/methods , Brazil , Veterinary Drugs/analysis , Limit of Detection , Muscles/chemistry
2.
Food Res Int ; 152: 110930, 2022 02.
Article in English | MEDLINE | ID: mdl-35181100

ABSTRACT

Oil-in-water (O/W) emulsions stabilized by cellulose nanocrystals (CNC) and/or sunflower proteins (SFP) were produced, aiming to study the effects of each and the mixture of these stabilizers on the interfacial behavior and physicochemical properties of O/W emulsions. The presence of CNC (non-surface activity compound) did not affect SFP solutions' adsorption kinetics since there were no differences in the interfacial tension curves of SFP and mixtures of stabilizers over time. However, either stabilizer provided alone high resistance against droplet coalescence over time (no evidence of oiling-off and no difference in the mean droplet size values), even systems with less viscoelastic interface (2 % CNC). Although droplet coalescence was prevented by steric hindrance and reduction of interfacial tension between the oil-water phases provided by CNC and SFP, respectively, these emulsions were unstable to the creaming phenomenon. Only the mixture of these stabilizers was able to prevent both destabilization mechanisms, initially by adsorption and anchoring of SFP on the interface, followed by adsorption of CNC in the free interface spaces, and finally by the interaction of non-adsorbed CNC particles in the continuous phase, which led to an increase in system viscosity. Thus, based on the results of interfacial properties and emulsions characteristics, we had a better understanding of stabilization mechanisms of O/W emulsions by a food-grade particle and a plant-derived protein.


Subject(s)
Helianthus , Nanoparticles , Cellulose/chemistry , Emulsions/chemistry , Nanoparticles/chemistry , Oils/chemistry
3.
Food Chem ; 325: 126953, 2020 Apr 30.
Article in English | MEDLINE | ID: mdl-32387940

ABSTRACT

This article aims to develop and validate a multivariate model for quantifying Robusta-Arabica coffee blends by combining near infrared spectroscopy (NIRS) and total reflection X-ray fluorescence (TXRF). For this aim, 80 coffee blends (0.0-33.0%) were formulated. NIR spectra were obtained in the wavenumber range 11100-4950 cm-1 and 14 elements were determined by TXRF. Partial least squares models were built using data fusion at low and medium levels. In addition, selection of predictive variables based on their importance indices (SVPII) improved results. The best model reduced the number of variables from 1114 to 75 and root mean square error of prediction from 4.1% to 1.7%. SVPII selected NIR regions correlated with coffee components, and the following elements were chosen: Ti, Mn, Fe, Cu, Zn, Br, Rb, Sr. The model interpretation took advantage of the data fusion between atomic and molecular spectra in order to characterize the differences between these coffee varieties.

4.
Food Chem ; 281: 71-77, 2019 May 30.
Article in English | MEDLINE | ID: mdl-30658767

ABSTRACT

This paper describes a robust multivariate model for quantifying and characterizing blends of Robusta and Arabica coffees. At different degrees of roasting, 120 ground coffee blends (0.0-33.0%) were formulated. Spectra were obtained by two different techniques, attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and paper spray mass spectrometry (PS-MS). Partial least squares (PLS) models were built individually with the two types of spectra. Nevertheless, better predictions were obtained by low and medium-level data fusion, taking advantage from the synergy between these two data sets. Data fusion models were improved by variable selection, using genetic algorithms (GA) and ordered predictors selection (OPS). The smallest prediction errors were provided by OPS low-level data fusion model. The number of variables used for regression was reduced from 2145 (full spectra) to 230. Model interpretation was performed by assigning some of the selected variables to specific coffee components, such as trigonelline and chlorogenic acids.


Subject(s)
Coffee/chemistry , Spectrophotometry, Infrared , Coffea/chemistry , Food Analysis , Food Handling , Reproducibility of Results , Spectroscopy, Fourier Transform Infrared
5.
Photomed Laser Surg ; 30(3): 172-8, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22283620

ABSTRACT

OBJECTIVE: The purpose of this study was to evaluate the clinical effectiveness of a LED phototherapy prototype apparatus in the healing of nipple trauma in breastfeeding women. BACKGROUND DATA: There is no scientific evidence of an effective treatment for nipple trauma. METHODS: The experimental group was treated with orientation on nipple care and adequate breastfeeding techniques in addition to active LED phototherapy. The control group was treated with orientation on nipple care and adequate breastfeeding techniques in addition to placebo LED phototherapy. Participants were treated twice a week, for a total of eight sessions. Healing of the nipple lesions was measured by a reduction in their area, and decrease in pain intensity was measured in accordance with an 11-point Pain Intensity Numerical Rating Scale and a standard 7-point patient global impression of change. RESULTS: Statistically significant reductions in measured nipple lesion area (p<0.001) were observed for both the experimental and control groups with an increase in the number of treatment sessions. A significant difference between the experimental and control groups was observed for the healing of nipple lesions (p<0.001). The pain intensity was significantly reduced only in the experimental group (p<0.001). CONCLUSIONS: Preliminary results demonstrated the prototype apparatus for LED phototherapy to be an effective tool in accelerating the healing of nipple trauma.


Subject(s)
Breast Diseases/radiotherapy , Breast Feeding/adverse effects , Dermatitis/radiotherapy , Low-Level Light Therapy/methods , Nipples/injuries , Wound Healing , Administration, Topical , Adult , Breast Diseases/etiology , Breast Diseases/physiopathology , Dermatitis/etiology , Dermatitis/physiopathology , Dermatologic Agents/therapeutic use , Double-Blind Method , Female , Humans , Nipples/physiopathology , Pain Measurement , Pilot Projects , Risk Assessment , Severity of Illness Index , Skin Care/methods , Statistics, Nonparametric , Wound Healing/physiology , Young Adult
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