Methodology for predicting oily mixture properties in the mathematical modeling of molecular distillation

A methodology for predicting the thermodynamic and transport properties of a multi-component oily mixture, in which the different mixture components are grouped into a small number of pseudo components is shown. This prediction of properties is used in the mathematical modeling of molecular distillation, which consists of a system of differential equations in partial derivatives, according to the principles of the Transport Phenomena and is solved by an implicit finite difference method using a computer code. The mathematical model was validated with experimental data, specifically the molecular distillation of a deodorizer distillate (DD) of sunflower oil. The results obtained were satisfactory, with errors less than 10% with respect to the experimental data in a temperature range in which it is possible to apply the proposed method.Fil: Gayol, Maria Fernanda. Universidad Nacional de Rio Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Pramparo, Maria del Carmen. Universidad Nacional de Rio Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; ArgentinaFil: Miro Erdmann, Silvia M.. Universidad Nacional de San Luis. Facultad de Ingeniería y Ciencias Agropecuarias; Argentin

Sensory quality of milk fat with low cholesterol content fractioned by molecular distillation

Anhydrous milk fat (AMF) is a valuable ingredient in several industries, but its cholesterol content is a disadvantage because it is associated with several diseases. The objective of this study was to remove the largest possible amount of cholesterol from AMF by molecular distillation and to analyze the sensory properties of the obtained product. AMF was subjected to various molecular distillation arrangements. RESULTS: The first set of experiments involved molecular distillations performed over a range of evaporation temperatures. Then, according to the outcome of the first set of experiments, a second set of experiments was carried out in order to study the effect of the feeding flow rate. Finally, the number of distillation stages was modified. The best results were obtained in a three-stage arrangement, in which ∼60% of cholesterol was removed with a 30.48% distillate yield. The sensory properties of this distillation cut were also the most similar to those of the untreated milk fat.Fil: Berti, Julia. Universidad Nacional de Rio Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Grosso, Nelson. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Fernandez, Hector. Universidad Nacional de Rio Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Pramparo, Maria del Carmen. Universidad Nacional de Rio Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; ArgentinaFil: Gayol, Maria Fernanda. Universidad Nacional de Rio Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentin

Comparison of seven prognostic tools to identify low-risk pulmonary embolism in patients aged <50 years

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Science and myth: the case of the dinosaur

Tema del mesEste trabajo, encuadrado en un cuento hiperbreve, plantea que los mitos nacen y transitan por una singular cornisa entre un proceder científico epistemológico y otro que no es tal, pudiendo disparar búsquedas científicas o bien empantanarlas e intenta demostrar, asimismo, que los dinosaurios no han escapado a estas consideraciones. Se efectúa un breve recorrido por los registros fósiles disponibles sobre la evolución de los dinosaurios hasta el letal destino de este superorden y su actual conocimiento. A su vez, se citan algunos mitos universales vinculados con los dinosaurios y su comparación con la evidencia científica, mencionándose igualmente otros más puntuales y regionales como los grifos, M’Koo, Mokéle-Mbémbé, Ogopogo, Chac o Chan, Teyú-Jaguá, Mboi-Tui, Lizzie, Nessie, el “monstruo” del lago Lacar y Nahuelito, ligados con dinosaurios, en forma estricta o no. Se concluye que el debate científico sobre los dinosaurios se halla abierto y proseguirá, desde que sus connotaciones míticas, que lo precedieron y forman parte de nuestra herencia cultural como fusión de pensamiento mágico, creencias religiosas y narraciones trasvasadas, se retroalimenta con cada hallazgo hecho a este respecto. Esta convicción se sustenta en que tales ficciones, atemporales y permanentes, enlazan simultáneamente lo externo y perceptible con nuestros anhelos, esperanzas y temores, por lo que el dinosaurio continúa batallando entre una presencia mítica, irracional e imprecisa y otra que avanza y retrocede configurando trabajosamente lo que denominamos cienciaCentered in a hyper-short story, this paper raises that myths are born and walks along a particular cornice between a scientific behavior and another very far from it, triggering scientific researches or leading them towards swampy zones. Likewise, it intends to demonstrate that dinosaurs have not escaped to these previous considerations. A summary about the available fossil registers on the evolution of dinosaurs from their birth to their lethal fate and distinct reflections about the current knowledge referred to this superorder are made. Some related universal myths are cited and a comparison with scientific evidence is carried out. Moreover, other more regional and focal myths, strictly linked with dinosaurs or not, are mentioned ( gryphon, M’Koo, Mokéle-Mbémbé, Ogopogo, Chac or Chan, Teyú-Jaguá, Mboi-Tui, Lizzie, Nessie, the lake Lacar “monster” and Nahuelito, among them). We conclude that the debate about dinosaurs is still open and will continue since its mythical connotations, which preceded that discussion and are part of our cultural inheritance by merging magic thinking, religious beliefs and transferred narrations, fuel the aforesaid debate with each new finding made in this regard. This conviction is supported in the permanent characteristics of these fictions involving at the same time what is external and perceptible with our wishes, hopes and fears. In this context, dinosaurs still endure between a mythical, irrational and imprecise presence and another one, going forth, going back and laboriously shaping what we call scienc

Thymol enrichment from oregano essential oil by molecular distillation

The objectives of this study were to obtain fractions enriched in thymol by molecular distillation of oregano essential oil and to evaluate their antioxidant properties. In addition, this operation was modelled considering the effects of evaporation temperature and feeding flow on thymol concentration in the residue fractions by means of artificial neural networks (ANN). All residue fractions had a higher percentage of thymol than the distillates. The thymol composition in the residue fractions reached values up to 2.4-fold higher than in oregano essential oil. Higher concentrations of thymol produced lower values for IC50 according to DPPH technique, indicating an increase in antioxidant properties. During the storage test, all the residue fractions analysed showed better peroxide, conjugated dienes and conjugated trienes values than distillates and OEO when they were used in sunflower oil samples. The results of storage stability showed that residues and BHT are very good antioxidants. The ANN created demonstrated good predictive ability for the operation of molecular distillation of oregano essential oil.Fil: Borgarello, Ana Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Rio Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; ArgentinaFil: Mezza, Gabriela Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Rio Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; ArgentinaFil: Pramparo, Maria del Carmen. Universidad Nacional de Rio Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; ArgentinaFil: Gayol, Maria Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Rio Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; Argentin

Optimisation of omega-3 concentration and sensory analysis of chia oil

The objective of this study was to obtain concentrated α-linolenic acid ethyl esters from chia oil with values of chemical indicators permitted by current legislation for edible oils and its sensory quality was determined. In the transesterification reaction, sodium hydroxide catalyst concentration and alcohol: oil molar ratios were studied. The model of transesterification with artificial neural networks showed an optimum at a catalyst concentration of 0.387 gNaOH/100goil and a 12.7:1 alcohol: oil molar ratio. The urea complexation was carried out at weight ratios urea: omega-3 fatty acid ethyl esters of 0.5:1, crystallisation at −10 °C for 24 h. Molecular distillation was carried out in one and two stages, where the best results were provided by using one stage, a distillation temperature of 85 °C and pressure of 1.579 × 10−5 atm. The combination of transesterification, urea complexation and molecular distillation allowed obtaining an increase of 24.50 % of omega -3 fatty acids ethyl esters in the final product. This product contains 781.35 g/ kg omega-3, and values of free fatty acids and peroxide of 0.693 % and 1.052 meqO2/kg, respectively. Chia oil presents the higher values of nutty and cream flavour (positive attributes), and turbidity. In the final product these attributes diminishes considerably.Fil: Sosa, Martin Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; ArgentinaFil: Magallanes, Leisa Maria. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; ArgentinaFil: Grosso, Nelson. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Pramparo, Maria del Carmen. Universidad Nacional de Río Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; ArgentinaFil: Gayol, Maria Fernanda. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; Argentin

Competencias Investigartivas. Su desarrollo en carreras del Área de la Salud.

Algunos formatos curriculares priorizan actualmente el desarrollo de competencias y, en tal sentido, en el presente ensayo proponemos acciones formadoras de competencias investigativas concretas y sistemáticas que pueden instalarse en el currículo de carreras del Área de la Salud. La propuesta busca crear un saber hacer fundamentado superador del mero saber. Se puntualizan conceptos, se detallan las competencias investigativas del saber, del ser y del hacer, se postulan acciones para su desarrollo y se tratan sus posibles impactos. El planteo se halla sustentado en experiencias recogidas por los autores durante la formación de becarios-alumnos, docentes, investigadores y doctorandos, algunas de las cuales están difundidas en publicaciones previas. Palabras claves:  competencias investigativas, área de la salu

Antioxidant activity of rosemary essential oil fractions obtained by molecular distillation and their effect on oxidative stability of sunflower oil

The objective of this study was to evaluate the antioxidant activity of rosemary essential oil fractions obtained by molecular distillation (MD) and investigate their effect on the oxidative stability of sunflower oil. MD fractions were prepared in a series of low-pressure stages where rosemary essential oil was the first feed. Subsequently, a distillate (D1) and residue (R1) were obtained and the residue fraction from the previous stage used as the feed for the next. The residue fractions had the largest capacity to capture free radicals, and the lowest peroxide values, conjugated dienes and conjugated trienes. The antioxidant activity of the fractions was due to oxygenated monoterpenes, specifically α-terpineol and cis-sabinene hydrate. Oxidative stability results showed the residues (R1 and R4) and butylated hydroxytoluene had greater antioxidant activity than either the distillate fractions or original rosemary essential oil. The residue fractions obtained by short path MD of rosemary essential oil could be used as a natural antioxidants by the food industry.Fil: Mezza, Gabriela Natalia. Universidad Nacional de Río Cuarto. Facultad de Ingeniería; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Borgarello, Ana Valeria. Universidad Nacional de Río Cuarto. Facultad de Ingeniería; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Grosso, Nelson. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Fernandez, Hector. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales; ArgentinaFil: Pramparo, Maria del Carmen. Universidad Nacional de Río Cuarto. Facultad de Ingeniería; ArgentinaFil: Gayol, Maria Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; Argentin

Recovery of acid corn oil from the bioalcohol industry by molecular distillation

The objective of this work was to reduce the acidity of acid corn oil for its subsequent use as edible oil. Also, its composition in tocopherols was determined. This oil is obtained as a by-product of corn alcohol production on an industrial scale and is currently used as a raw material in the biodiesel industry. The composition in tocopherols and fatty acids of acid corn oil was determined by gas chromatography and experiments of molecular distillation were carried out at different temperatures between 110 °C and 190 °C with a Volumetric flow rate of 0.5 to 2 mL min-1 and a pressure of 5.10-5 atm. It was possible to reduce its acidity from 9.44% up to values less than 0.3% in the residue, with distillation temperatures higher than 180 °C; also, in the distillate the tocopherols were recovered, with concentrations up to 13360 ppm.CONCLUSION: It was possible to decrease the acidity and purify tocopherols from acid corn oil by molecular distillation, obtaining a residue with an acidity acceptable for human consumption and a distillate with a high tocopherols content. Therefore, using molecular distillation, added value was given to a by-product of the bioalcohol industry.Fil: Miró Erdmann, Silvia Marcela. Universidad Nacional de San Luis. Facultad de Ingeniería y Ciencias Agropecuarias; ArgentinaFil: Magallanes, Leisa Maria. Universidad Nacional de Río Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Tarditto, Lorena Viviana. Universidad Nacional de Río Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Prizzon, Antonella. Universidad Nacional de Río Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; ArgentinaFil: Pramparo, Maria del Carmen. Universidad Nacional de Río Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; ArgentinaFil: Gayol, Maria Fernanda. Universidad Nacional de Río Cuarto. Instituto para el Desarrollo Agroindustrial y de la Salud. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto para el Desarrollo Agroindustrial y de la Salud; Argentin