Evaluación de fibra dietética, isoflavonas y compuestos fenólicos con propiedades antioxidantes y antimicrobianas de quinoa (Chenopodium quinoa Willd.)

The consumption of quinoa (Chenopodium quinoa Willd.) has been steadily increasing due to its high nutritional value and health benefits associated with its high antioxidant capacity. The objective of this study was to determine the contents of dietary fiber, polyphenols, flavonoids and isoflavones, and how they contribute to the antioxidant and antimicrobial activity of six ecotypes of quinoa cultivated in three different zones of Chile. The ecotypes studied were: Ancovinto and Cancosa (Northern zone), Cáhuil and Faro (Central zone), and Regalona and Villarrica (Southern zone). The results indicate that all Chilean quinoa ecotypes could be considered as good sources of dietary fiber (12.23 g 100 g-1 dry matter) and polyphenols (161.32 mg Gallic Acid Equivalents (GAE) 100 g-1 dry matter). The North and Central ecotypes exhibited the highest isoflavone concentration. The Northern Cancosa was the ecotype that showed the highest flavonoid content (211.06 mg Catechin Equivalents (CAE) 100 g-1 dry matter). Based on the ORAC (Oxygen Radical Absorbance Capacity) assay, Ancovinto, Cancosa and Faro presented the highest antioxidant capacity (67.6 mmol Trolox Equivalents (TE) 100 g-1 dry matter). Regarding antimicrobial activity, Regalona ecotype showed the best performance against Saccharomyces cerevisiae and Listeria innocua. The bioactive compounds found in this study add new knowledge to the antioxidant and antimicrobial activity of Chilean quinoa seeds.El consumo de quinua (Chenopodium quinoa Willd.) está aumentando debido a su valor nutricional y beneficios para la salud relacionados con su capacidad antioxidante. El objetivo de presente estudio fue determinar los contenidos de fibra dietética, polifenoles, flavonoides e isoflavonas, y cómo estos compuestos contribuyen a la actividad antioxidante y antimicrobiana de seis ecotipos de quinua cultivados en tres zonas de Chile. Las muestras de quinua de la zona Norte se denominan Ancovinto y Cancosa, de la zona Centro se llaman Cáhuil y Faro, y de la zona Sur se denominan Regalona y Villarrica. Los resultados mostraron que todos los ecotipos de quinua chilena pueden considerarse buena fuente de fibra dietética (12,23 g 100 g-1 materia seca) y de polifenoles (161,32 mg de Equivalentes de Acido Gálico (EAG) 100 g-1 materia seca). Los ecotipos de la zona Norte y Centro mostraron la mayor concentración de isoflavonas. El ecotipo Cancosa, de la zona Norte, fue el que mostró el mayor contenido de flavonoides (211,06 mg Equivalentes de Catequina (ECA) 100 g-1 materia seca). Basado en el ensayo ORAC (del inglés Oxigen Radical Absorbance Capacity), los ecotipos Ancovinto, Cancosa y Faro, presentaron en promedio la mayor capacidad antioxidante (67,6 mmol de Equivalentes Trolox (ET) 100 g-1 materia seca). El ecotipo Regalona mostró la más alta actividad antimicrobiana frente a Saccharomyces cerevisiae y Listeria innocua. Los compuestos bioactivos encontrados en este estudio aportan nuevos conocimientos a la actividad antioxidante y antimicrobiana de las semillas de quinua chilena.Fil: Vega Gálvez, Antonio. Universidad de La Serena; ChileFil: Zura, Liliana. Universidad de La Serena; ChileFil: Lutz, Mariane. Universidad de Vlparaíso; ChileFil: Jagus, Rosa Juana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; ArgentinaFil: Agüero, Maria Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; ArgentinaFil: Pastén, Alexis. Universidad de La Serena; ChileFil: Di Scala, Karina Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; ArgentinaFil: Uribe, Elsa. Universidad de La Serena; Chil

An artificial neural network model for prediction of quality characteristics of apples during convective dehydration

In this study, the effects of hot-air drying conditions on color, water holding capacity, and total phenolic content of dried apple were investigated using artificial neural network as an intelligent modeling system. After that, a genetic algorithm was used to optimize the drying conditions. Apples were dried at different temperatures (40, 60, and 80 °C) and at three air flow-rates (0.5, 1, and 1.5 m/s). Applying the leave-one-out cross validation methodology, simulated and experimental data were in good agreement presenting an error < 2.4 %. Quality index optimal values were found at 62.9 °C and 1.0 m/s using genetic algorithm.Centro de Investigación y Desarrollo en Criotecnología de AlimentosFacultad de Ingenierí

Propriedades químicas e físicas do gel de aloe vera (Aloe barbadensis Miller) armazenado após processamento sob alta pressão hidrostática

&e aim of this study was to evaluate the in[uence of high hydrostatic pressure (150, 250, 350, 450, and 550 MPa), applied for 5 minutes, on antioxidant capacity, total phenolic content, color, Frmness, rehydration ratio, and water holding capacity of aloe vera gel stored for 60 days at 4 °C. &e analyzed properties of the pressurized gel showed signiFcant changes a\er the storage period. &e highest value of total phenolic content was found at 550 MPa. However, a decrease in the antioxidant capacity was observed for all pressurized gel samples when compared to the control sample (p < 0.05). &e smallest changes in product color were observed at pressure levels between 150 and 250 MP. &e application of high hydrostatic pressure resulted in lower gel Frmness, and the lowest value was found at 150 MPa (p < 0.05). On the other hand, the untreated sample showed a greater decrease in Frmness, indicating that high pressure processing preserves this property. &e application of high hydrostatic pressure exhibited modiFcations in the food matrix, which were evaluated in terms of rehydration ratio and water holding capacity.O objetivo deste estudo foi avaliar o efeito da aplicação de altas pressões hidrostáticas (150, 250, 350, 450 e 550 MPa) aplicadas durante 5 minutos sobre a atividade antioxidante, concentração de polifenóis totais, cor, Frmeza, taxa de reidratação e capacidade de retenção de água do gel de aloe vera armazenado durante 60 dias a 4 °C. As propriedades analisadas do gel pressurizado mostraram mudanças signiFcativas depois de armazenadas. Para pressões de 550 Mpa, registrou-se o maior aumento de polifenóis totais. No entanto, observou-se uma diminuição da capacidade antioxidante em todas as amostras, em comparação com a amostra não tratada (p < 0,05). As alterações de cor foram menores para pressões entre 150 e 250 MPa. A aplicação de altas pressões hidrostáticas diminuiu a Frmeza do gel, registrando-se o menor valor para 150 MPa (p < 0,05). Por outro lado, o tratamento sem pressão mostrou uma maior perda de Frmeza, indicando que o tratamento por altas pressões conserva esta propriedade. A aplicação de altas pressões evidenciou modiFcações da matriz do alimento, avaliadas como taxa de reidratação e capacidade de retenção de água.Fil: Di Scala, Karina Cecilia. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Vega Gálvez, Antonio. Universidad de La Serena; ChileFil: Ah Hen, Kong. Universidad Austral de Chile; ChileFil: Nuñez Mancilla, Yissleen. Universidad de La Serena; ChileFil: Tabilo Minizaga, Gipsy. Universidad del Bio Bio; ChileFil: Perez Won, Mario. Universidad de La Serena; ChileFil: Giovagnoli, Claudia. Universidad de La Serena; Chil

Thermodynamic Properties, Sorption Isotherms and Glass Transition Temperature of Cape Gooseberry (Physalis peruviana L.)

U ovom su radu gravimetrijski određene izoterme vlaženja (adsorpcije i desorpcije vode) svježih i sušenih bobica peruanske jagode (Physalis peruviana L.) pri temperaturama od 20, 40 i 60 °C. Dobiveni su podaci usklađeni uz pomoć sljedećih modela: Guggenheim-Anderson-De Boerov (GAB), Brunauer-Emmett-Tellerov (BET), Hendersonov, Cauriejev, Smithov, Oswinov, Halseyev i Iglesias-Chirifeov model. Za procjenu modela upotrijebljena je metoda najmanjih kvadrata i nelinearna regresijska analiza. Iglesias-Chirifeov je model bio najprikladniji za opisivanje rezultata pokusa. Entalpija je adsorpcije određena iz podataka o ravnoteži vlaženja pomoću Clausius-Clapeyronove jednadžbe, te je utvrđeno da se ona eksponencijalno smanjuje s porastom udjela vlage. Primjenom je teorije kompenzacije entalpije i entropije na izoterme vlaženja dokazano da su adsorpcija i desorpcija vode ovisile o entalpiji procesa. Temperatura je staklastog prijelaza (Tg) određena diferencijalnom pretražnom kalorimetrijom, a dobiveni su podaci uspoređeni s udjelom vlage pomoću Gordon-Taylorovog, Roosovog i Khaloufijevog modela, koji su bili najprikladniji za procjenu temperature pri kojoj dolazi do staklastog prijelaza bobica peruanske jagode.Adsorption and desorption isotherms of fresh and dried Cape gooseberry (Physalis peruviana L.) were determined at three temperatures (20, 40 and 60 °C) using a gravimetric technique. The data obtained were fitted to several models including Guggenheim-Anderson- De Boer (GAB), Brunauer-Emmett-Teller (BET), Henderson, Caurie, Smith, Oswin, Halsey and Iglesias-Chirife. A non-linear least square regression analysis was used to evaluate the models. The Iglesias-Chirife model fitted best the experimental data. Isosteric heat of sorption was also determined from the equilibrium sorption data using the Clausius-Clapeyron equation and was found to decrease exponentially with increasing moisture content. The enthalpy-entropy compensation theory was applied to the sorption isotherms and indicated an enthalpy-controlled sorption process. Glass transition temperature (Tg) of Cape gooseberry was also determined by differential scanning calorimetry and modelled as a function of moisture content with the Gordon-Taylor, the Roos and the Khalloufi models, which proved to be excellent tools for predicting glass transition of Cape gooseberry

An artificial neural network model for prediction of quality characteristics of apples during convective dehydration

In this study, the effects of hot-air drying conditions on color, water holding capacity, and total phenolic content of dried apple were investigated using artificial neural network as an intelligent modeling system. After that, a genetic algorithm was used to optimize the drying conditions. Apples were dried at different temperatures (40, 60, and 80 °C) and at three air flow-rates (0.5, 1, and 1.5 m/s). Applying the leave-one-out cross validation methodology, simulated and experimental data were in good agreement presenting an error < 2.4 %. Quality index optimal values were found at 62.9 °C and 1.0 m/s using genetic algorithm.Centro de Investigación y Desarrollo en Criotecnología de AlimentosFacultad de Ingenierí

Role of age and comorbidities in mortality of patients with infective endocarditis

[Purpose]: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality. [Methods]: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups:<65 years,65 to 80 years,and ≥ 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk. [Results]: A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 ≥ 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients ≥80 years who underwent surgery were significantly lower compared with other age groups (14.3%,65 years; 20.5%,65-79 years; 31.3%,≥80 years). In-hospital mortality was lower in the <65-year group (20.3%,<65 years;30.1%,65-79 years;34.7%,≥80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%,≥80 years; p = 0.003).Independent predictors of mortality were age ≥ 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32–3.34), CCI ≥ 3 (HR:1.62; 95% CI:1.39–1.88),and non-performed surgery (HR:1.64;95% CI:11.16–1.58).When the three age groups were compared,the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality. [Conclusion]: There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group