Élia Fernandes - Academia.edu (original) (raw)

Papers by Élia Fernandes

Journal of Food Measurement and Characterization, Jan 8, 2024

The purpose of this study was to evaluate the applicability of an alternative analytical techniqu... more The purpose of this study was to evaluate the applicability of an alternative analytical technique to the reference method for phosphorus detection in meat and meat products established by ISO 2294:1974, revised by ISO 23776:2021. When an analytical method is modified or a new one is developed and implemented, it should be validated before being accepted for routine determinations. Furthermore, it is necessary to demonstrate that the new or alternative method has good performance characteristics in comparison with the reference method. Therefore, a comparison of the performance of the alternative and the reference method should be made. In the present study, a statistical evaluation of the calibration model of the alternative method was made with data from interlaboratory studies made in five consecutive years using fifty analyses of meat and meat products. The statistical parameters evaluated over time for the calibration curve were the y-intercept and slope; correlation and linearity; analytical limits: detection and quantification; working range; and accuracy (precision and trueness). In the interlaboratory tests, the results obtained by the alternative analytical method were compared with those obtained by the reference method, and their performance in these tests was also evaluated. The results obtained by the alternative method indicated better accuracy than the reference method due to lower relative errors, more precision, and a good trueness evaluation through lower absolute values of the z-score. The study demonstrated that the phosphorus alternative method is applicable for the determination of total phosphorus in the matrix of meat and meat products.

Frontiers in Sustainable Food Systems

The Atlantic horse mackerel (Trachurus trachurus) is a globally favored fish due to its abundance... more The Atlantic horse mackerel (Trachurus trachurus) is a globally favored fish due to its abundance, nutritional value, and affordability, but it faces quality preservation challenges. To address this, this study aimed to enhance its value by creating low-salt smoked products with natural bioactive compounds from seafood and forest sources. The fish filets were divided into four groups: one as a control, and the others were treated with various bioactive extract solutions, specifically pine bark, mussels, and microalgae. After 15 days of storage at 4°C, significant differences in properties were observed. Moisture and salt had an inverse relationship, with decreasing moisture and pH over time. Oxidation levels remained acceptable, although sensory quality was affected by storage. Microbiological analysis uncovered high contamination levels in certain samples at specific points in time, although no pathogens such as Salmonella spp. or Listeria monocytogenes were detected. While microal...

HAL (Le Centre pour la Communication Scientifique Directe), Aug 27, 2018

Journal of Clinical Virology, 2021

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Millennium: Journal of International Studies, 2019

espanolIntroduccion: La corteza de pino es un residuo agroindustrial proveniente de la industria ... more espanolIntroduccion: La corteza de pino es un residuo agroindustrial proveniente de la industria maderera y representa una fuente de compuestos fenolicos. Estos compuestos tienen varias propiedades beneficas siendo ellas antioxidantes, antimicrobianas, antiinflamatorias, cardiovasculares, entre otras. Objetivos: El objetivo de este trabajo fue estudiar la composicion quimica de la corteza de Pinus pinaster Aiton subsp. atlantica y el perfil fenolico de sus extractos acuosos, etanolicos e hidroetanolicos. Metodos: Se analizo el contenido de humedad, cenizas, proteinas, grasa total y carbohidratos. La corteza se extrajo con agua, etanol o una mezcla de ambos en un aparato de Soxhlet y se determinaron el rendimiento de la extraccion, el contenido de compuestos fenolicos totales (CFT), la actividad antioxidante y el perfil fenolico mediante RP-HPLC-UV, en los extractos con CFT mas alto. Resultados: Los resultados obtenidos para la composicion quimica fueron: 63,43 de carbohidratos, 2,81...

Chemical Engineering Transactions, 2018

Pine bark extracts are a rich source of natural polyphenols with potential beneficial antioxidant... more Pine bark extracts are a rich source of natural polyphenols with potential beneficial antioxidant properties. The extraction yield, antioxidant activity, as well the type of polyphenols recovered not only depend on the extraction method but also on the solvent used for extraction. Thus, the aim of the present study was to ascertain the effect of different solvents on extraction yield, total phenolic content and antioxidant activity of extracts from Pinus pinaster subsp. atlantica, the major forest biomass of Northwest of Portugal. Soxhlet extractions with water, water/ethanol (1/1) and just ethanol, as solvents, were performed for 4 hours. Best results were obtained with the water/ethanol mixture. Overall, the solvent's performance was as follows: water/ethanol> ethanol> water.

Milk from two different cow breeds, Barrosa and Frisia, was studied. Within the same breed five a... more Milk from two different cow breeds, Barrosa and Frisia, was studied. Within the same breed five and four milk samples were taken respectively for chemical and microbiological analysis. The following chemical parameters were analysed in triplicate: Total Fat, Fatty Acids Identification and Quantification, Protein, Casein, Albumin, Non-protein Nitrogen, Vitamin A, Vitamin D, Phosphorus, Potassium, Sodium, Iron, Magnesium, Calcium, Ash, Total solids, Lactic acid and Acidity. In general terms milk from Barrosa breed showed higher values for all analysed parameters except for Total Fat, Total Solids and Vitamin D. Statistical analysis, by testing the chemical parameters all together using the Hotelling T2 test showed that milk samples from the two cow breeds were significantly different (α=0,05). Microbiological analysis (Total Viable Counts (30oC), Escherichia coli, Staphylococcus coagulase + and Listeria monocytogenes) was also performed. Staphylococcus coagulase + was found in one mil...

Water

The spatial patterns of chlorophyll a and bacteria were assessed in a temperate Atlantic tidal es... more The spatial patterns of chlorophyll a and bacteria were assessed in a temperate Atlantic tidal estuary during seasonal surveys, as well as in consecutive summer spring and neap tides. A box model approach was used to better understand spatial and temporal dynamics of these key estuarine descriptors. The Lima estuary (NW Portugal) was divided into boxes controlled by salinity and freshwater discharge and balance equations were derived for each variable, enabling the calculation of horizontal and vertical fluxes of plankton and, therefore, production or consumption rates. Chlorophyll a tended to burst within the oligohaline zone, whereas higher counts of bacteria were found in the mesohaline stretch. Whenever the water column was stratified, similar tide-independent trends were found for chlorophyll a and bacterial fluxes, with net growth in the upper less saline boxes, and consumption beneath the halocline. In the non-stratified upper estuary, other controls emerged for chlorophyll a...

Millenium - Journal of Education, Technologies, and Health

The Journal of Chemical Thermodynamics, 1995

The standard (p°= 0.1 MPa) molar enthalpies of combustion, at the temperature 298.15 K for crysta... more The standard (p°= 0.1 MPa) molar enthalpies of combustion, at the temperature 298.15 K for crystalline N,N′-ethylenebis(4-aminopent-3-en-2-one), {CH 3 COCH:C(CH 3 )NHCH 2 ·} 2 ,H 2 ,and N,N′-ethylenebis(3-amino-1-phenylbut-2-en-1-one),H 2 , {C 6 H 5 ...

Journal of the Chemical Society, Dalton Transactions, 1997

Page 1. DALTON J. Chem. Soc., Dalton Trans., 1997, Pages 1257–1262 1257 Energetics of metal–ligan... more Page 1. DALTON J. Chem. Soc., Dalton Trans., 1997, Pages 1257–1262 1257 Energetics of metal–ligand binding in copper(II) and nickel(II) complexes of two Schiff bases Manuel AV Ribeiro da Silva,* Maria DMC Ribeiro da ...

Journal of Food Measurement and Characterization, Jan 8, 2024

The purpose of this study was to evaluate the applicability of an alternative analytical techniqu... more The purpose of this study was to evaluate the applicability of an alternative analytical technique to the reference method for phosphorus detection in meat and meat products established by ISO 2294:1974, revised by ISO 23776:2021. When an analytical method is modified or a new one is developed and implemented, it should be validated before being accepted for routine determinations. Furthermore, it is necessary to demonstrate that the new or alternative method has good performance characteristics in comparison with the reference method. Therefore, a comparison of the performance of the alternative and the reference method should be made. In the present study, a statistical evaluation of the calibration model of the alternative method was made with data from interlaboratory studies made in five consecutive years using fifty analyses of meat and meat products. The statistical parameters evaluated over time for the calibration curve were the y-intercept and slope; correlation and linearity; analytical limits: detection and quantification; working range; and accuracy (precision and trueness). In the interlaboratory tests, the results obtained by the alternative analytical method were compared with those obtained by the reference method, and their performance in these tests was also evaluated. The results obtained by the alternative method indicated better accuracy than the reference method due to lower relative errors, more precision, and a good trueness evaluation through lower absolute values of the z-score. The study demonstrated that the phosphorus alternative method is applicable for the determination of total phosphorus in the matrix of meat and meat products.

Frontiers in Sustainable Food Systems

The Atlantic horse mackerel (Trachurus trachurus) is a globally favored fish due to its abundance... more The Atlantic horse mackerel (Trachurus trachurus) is a globally favored fish due to its abundance, nutritional value, and affordability, but it faces quality preservation challenges. To address this, this study aimed to enhance its value by creating low-salt smoked products with natural bioactive compounds from seafood and forest sources. The fish filets were divided into four groups: one as a control, and the others were treated with various bioactive extract solutions, specifically pine bark, mussels, and microalgae. After 15 days of storage at 4°C, significant differences in properties were observed. Moisture and salt had an inverse relationship, with decreasing moisture and pH over time. Oxidation levels remained acceptable, although sensory quality was affected by storage. Microbiological analysis uncovered high contamination levels in certain samples at specific points in time, although no pathogens such as Salmonella spp. or Listeria monocytogenes were detected. While microal...

HAL (Le Centre pour la Communication Scientifique Directe), Aug 27, 2018

Journal of Clinical Virology, 2021

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Millennium: Journal of International Studies, 2019

espanolIntroduccion: La corteza de pino es un residuo agroindustrial proveniente de la industria ... more espanolIntroduccion: La corteza de pino es un residuo agroindustrial proveniente de la industria maderera y representa una fuente de compuestos fenolicos. Estos compuestos tienen varias propiedades beneficas siendo ellas antioxidantes, antimicrobianas, antiinflamatorias, cardiovasculares, entre otras. Objetivos: El objetivo de este trabajo fue estudiar la composicion quimica de la corteza de Pinus pinaster Aiton subsp. atlantica y el perfil fenolico de sus extractos acuosos, etanolicos e hidroetanolicos. Metodos: Se analizo el contenido de humedad, cenizas, proteinas, grasa total y carbohidratos. La corteza se extrajo con agua, etanol o una mezcla de ambos en un aparato de Soxhlet y se determinaron el rendimiento de la extraccion, el contenido de compuestos fenolicos totales (CFT), la actividad antioxidante y el perfil fenolico mediante RP-HPLC-UV, en los extractos con CFT mas alto. Resultados: Los resultados obtenidos para la composicion quimica fueron: 63,43 de carbohidratos, 2,81...

Chemical Engineering Transactions, 2018

Pine bark extracts are a rich source of natural polyphenols with potential beneficial antioxidant... more Pine bark extracts are a rich source of natural polyphenols with potential beneficial antioxidant properties. The extraction yield, antioxidant activity, as well the type of polyphenols recovered not only depend on the extraction method but also on the solvent used for extraction. Thus, the aim of the present study was to ascertain the effect of different solvents on extraction yield, total phenolic content and antioxidant activity of extracts from Pinus pinaster subsp. atlantica, the major forest biomass of Northwest of Portugal. Soxhlet extractions with water, water/ethanol (1/1) and just ethanol, as solvents, were performed for 4 hours. Best results were obtained with the water/ethanol mixture. Overall, the solvent's performance was as follows: water/ethanol> ethanol> water.

Milk from two different cow breeds, Barrosa and Frisia, was studied. Within the same breed five a... more Milk from two different cow breeds, Barrosa and Frisia, was studied. Within the same breed five and four milk samples were taken respectively for chemical and microbiological analysis. The following chemical parameters were analysed in triplicate: Total Fat, Fatty Acids Identification and Quantification, Protein, Casein, Albumin, Non-protein Nitrogen, Vitamin A, Vitamin D, Phosphorus, Potassium, Sodium, Iron, Magnesium, Calcium, Ash, Total solids, Lactic acid and Acidity. In general terms milk from Barrosa breed showed higher values for all analysed parameters except for Total Fat, Total Solids and Vitamin D. Statistical analysis, by testing the chemical parameters all together using the Hotelling T2 test showed that milk samples from the two cow breeds were significantly different (α=0,05). Microbiological analysis (Total Viable Counts (30oC), Escherichia coli, Staphylococcus coagulase + and Listeria monocytogenes) was also performed. Staphylococcus coagulase + was found in one mil...

Water

The spatial patterns of chlorophyll a and bacteria were assessed in a temperate Atlantic tidal es... more The spatial patterns of chlorophyll a and bacteria were assessed in a temperate Atlantic tidal estuary during seasonal surveys, as well as in consecutive summer spring and neap tides. A box model approach was used to better understand spatial and temporal dynamics of these key estuarine descriptors. The Lima estuary (NW Portugal) was divided into boxes controlled by salinity and freshwater discharge and balance equations were derived for each variable, enabling the calculation of horizontal and vertical fluxes of plankton and, therefore, production or consumption rates. Chlorophyll a tended to burst within the oligohaline zone, whereas higher counts of bacteria were found in the mesohaline stretch. Whenever the water column was stratified, similar tide-independent trends were found for chlorophyll a and bacterial fluxes, with net growth in the upper less saline boxes, and consumption beneath the halocline. In the non-stratified upper estuary, other controls emerged for chlorophyll a...

Millenium - Journal of Education, Technologies, and Health

The Journal of Chemical Thermodynamics, 1995

The standard (p°= 0.1 MPa) molar enthalpies of combustion, at the temperature 298.15 K for crysta... more The standard (p°= 0.1 MPa) molar enthalpies of combustion, at the temperature 298.15 K for crystalline N,N′-ethylenebis(4-aminopent-3-en-2-one), {CH 3 COCH:C(CH 3 )NHCH 2 ·} 2 ,H 2 ,and N,N′-ethylenebis(3-amino-1-phenylbut-2-en-1-one),H 2 , {C 6 H 5 ...

Journal of the Chemical Society, Dalton Transactions, 1997

Page 1. DALTON J. Chem. Soc., Dalton Trans., 1997, Pages 1257–1262 1257 Energetics of metal–ligan... more Page 1. DALTON J. Chem. Soc., Dalton Trans., 1997, Pages 1257–1262 1257 Energetics of metal–ligand binding in copper(II) and nickel(II) complexes of two Schiff bases Manuel AV Ribeiro da Silva,* Maria DMC Ribeiro da ...