Mostrando 1 - 20 Resultados de 20 Para Buscar 'Vásquez-Villalobos, Víctor', tiempo de consulta: 0.25s Limitar resultados
1
artículo
The Gompertz and logistic mathematical models in the Spirulina sp. growth kinetics were evaluated and were compared with a modeling through Backpropagation Artificial Neural Networks (BP- ANN). Spirulina was cultivated in a (3 L/min) of 500 mL aerated laboratory photobioreactor with 40W fluorescent lighting and 1W lighting Solid State (LED-Light Emitting Diode) obtaining 11.0 klx lighting with both systems. The LED lighting allowed to obtain a (ɑ) 0.90 high biomass value compared with that one obtained with fluorescent lighting of 0.82, as well as a greater growth rate μ=0.63 h-1 preceded by a shorter latency time λ = 0.34 h. The BP-ANN showed a good accuracy with respect to the Gompertz I corrected model for both the Spirulina sp cultivation case with fluorescent lighting and with LED displaying correlation coefficients (R) of the 0.993 and 0.994 order respectively, with regard to th...
2
artículo
The study focused on the influence of the variables seawater proportion (%) and bicarbonate concentration on Spirulina sp. biomass production, using a Central Composite Rotational Design (CCRD) to evaluate the optimal regions of biomass production (ϕ), adaptation phase (λ), specific growth rate (µ) and generation time (G), using for each treatment the Gompertz mathematical model. The highest values of biomass (ϕ) log N/N0: 0.93 were obtained at 168.8 hours; in a culture medium with pH 8.8±0.1; at a temperature of 25°C; with salinity of 1.2% and 1.6 gL of bicarbonate. The lowest value of ϕ was 0.45±0.01; coincidentally obtained in repetitions of the central point, using a salinity of 0.7% and 3.0g/L of bicarbonate; in a medium with pH 9.1±0.4 to 25°C; which shows the importance of salinity provided by the volume of seawater relative to bicarbonate, in the production of Spirulina...
3
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The sensory preference (sp) and shelf life of sensory acceptability (SLSA) of canned artichoke hearts were modeled using fuzzy logic (FL) and accelerated testing. The artichoke hearts were marinated in oil of sacha inchi (Plukenetia volubilis), soybean (Glycine max) and olive (Olea europea); and evaluated using a Ranking test with a semi-trained panel, to identify the best preference both for flavor (f) and limpidity (l). We evaluated a global sp through intersection (AND) and union (OR) fuzzy operations of f and l, using functions of triangular membership with the Mamdani method for defuzzificacion through 25 linguistic rules. The intersection showed the best modeling performance, with the highest sp value at 3.30 for the treatment with sacha inchi (50%), olive (25%) and soybean (25%) (p << 0.05) oil, which was subjected to accelerated testing at 37 °C, 49 °C, 55 °C and evaluat...
4
artículo
Two types of skimmed (fat 3%) goat’s milk fruit yogurt with mango (YM) and banana (YB) were stored at temperatures of 5 °C, 15 °C and 25 °C for 72 hours. Every 24 hours the pH, titratable acidity, total solids, fat and protein were analyzed. Sensory acceptability was also evaluated with 75 yogurt frequent consumers, who responded with "yes" or "no" to the question ¿would you consume this product? At the beginning pH, acidity, total solids, fat and protein were 4.35 and 4.36; 0.76% and 0.75%; 12.71% and 13.23%; 3.2% and 3.3%; 4.4% and 4.5%, for the YM and YB respectively, meeting known standards for cow's milk yogurt: range of acidity 0.5%-1.6%, fat maximum value 15% and protein minimum value 2.7%. The sensory acceptability of the YM and the YB was high, with 88.9% and 94.7%, respectively. During storage under accelerated conditions, pH decreased to 3.88 and 3.92; titrable acidity i...
5
artículo
The aim this work was to compare the extraction process optimization of total glucosinolates of maca flour (Lepidium meyenii) (ETGMF) using RS for Box-Behnken (RSBB) Design with that of GA, according to x1: temperature (°C), x2: ethanol (%), x3: ratio solvent/raw material and x4: extraction time (min). TG were identified and quantified using HPLC. The variables (x1, x2, x3, x4) that influence their extraction were evaluated using a RSBB with the software Statistica and Wolfram Mathematica for the AG. From the development of the RSBB, a second order equation with R2 = 0.74794, p = 1.88248E-10 << 0.05 with 11% average absolute error was obtained; it showed the consistency of the model. It was not possible to obtain an optimal value of the ETGMF using RSBB because of the existence of two optimal zones due to the configuration of a chair surface. After 2000 iterations using GA, the ma...
6
artículo
A bi-factorial experimental design was considered to assess moisture variation of sweet potato-quinoa-kiwicha flakes (SP-Q-K) caused by the changes in the rotational speed and steam pressure of a rotary drum dryer (RDD). As it is a design with discrete variables, there is a limitation in the modeling and optimization thus techniques of Artificial Intelligence (AI): Artificial Neural Networks (ANN), Fuzzy Logic (FL) and Genetic Algorithms (GA), were applied, and their prediction ability evaluated. Due to the limitation of data for proper training, the ANN did not allow a correct prediction of the experimental data. Response Surface Methodology (RSM) was employed to obtain the relational equation among the experimental variables, which was used as the objective function with GA, and this allowed moisture optimization. Because of this, it is recommended to integrate RSM and GA into optimiza...
7
artículo
The Gompertz and logistic mathematical models in the Spirulina sp. growth kinetics were evaluated and were compared with a modeling through Backpropagation Artificial Neural Networks (BP- ANN). Spirulina was cultivated in a (3 L/min) of 500 mL aerated laboratory photobioreactor with 40W fluorescent lighting and 1W lighting Solid State (LED-Light Emitting Diode) obtaining 11.0 klx lighting with both systems. The LED lighting allowed to obtain a (ɑ) 0.90 high biomass value compared with that one obtained with fluorescent lighting of 0.82, as well as a greater growth rate μ=0.63 h-1 preceded by a shorter latency time λ = 0.34 h. The BP-ANN showed a good accuracy with respect to the Gompertz I corrected model for both the Spirulina sp cultivation case with fluorescent lighting and with LED displaying correlation coefficients (R) of the 0.993 and 0.994 order respectively, with regard to th...
8
artículo
The study focused on the influence of the variables seawater proportion (%) and bicarbonate concentration on Spirulina sp. biomass production, using a Central Composite Rotational Design (CCRD) to evaluate the optimal regions of biomass production (ϕ), adaptation phase (λ), specific growth rate (µ) and generation time (G), using for each treatment the Gompertz mathematical model. The highest values of biomass (ϕ) log N/N0: 0.93 were obtained at 168.8 hours; in a culture medium with pH 8.8±0.1; at a temperature of 25°C; with salinity of 1.2% and 1.6 gL of bicarbonate. The lowest value of ϕ was 0.45±0.01; coincidentally obtained in repetitions of the central point, using a salinity of 0.7% and 3.0g/L of bicarbonate; in a medium with pH 9.1±0.4 to 25°C; which shows the importance of salinity provided by the volume of seawater relative to bicarbonate, in the production of Spirulina...
9
artículo
The sensory preference (sp) and shelf life of sensory acceptability (SLSA) of canned artichoke hearts were modeled using fuzzy logic (FL) and accelerated testing. The artichoke hearts were marinated in oil of sacha inchi (Plukenetia volubilis), soybean (Glycine max) and olive (Olea europea); and evaluated using a Ranking test with a semi-trained panel, to identify the best preference both for flavor (f) and limpidity (l). We evaluated a global sp through intersection (AND) and union (OR) fuzzy operations of f and l, using functions of triangular membership with the Mamdani method for defuzzificacion through 25 linguistic rules. The intersection showed the best modeling performance, with the highest sp value at 3.30 for the treatment with sacha inchi (50%), olive (25%) and soybean (25%) (p << 0.05) oil, which was subjected to accelerated testing at 37 °C, 49 °C, 55 °C and evaluat...
10
artículo
Two types of skimmed (fat 3%) goat’s milk fruit yogurt with mango (YM) and banana (YB) were stored at temperatures of 5 °C, 15 °C and 25 °C for 72 hours. Every 24 hours the pH, titratable acidity, total solids, fat and protein were analyzed. Sensory acceptability was also evaluated with 75 yogurt frequent consumers, who responded with "yes" or "no" to the question ¿would you consume this product? At the beginning pH, acidity, total solids, fat and protein were 4.35 and 4.36; 0.76% and 0.75%; 12.71% and 13.23%; 3.2% and 3.3%; 4.4% and 4.5%, for the YM and YB respectively, meeting known standards for cow's milk yogurt: range of acidity 0.5%-1.6%, fat maximum value 15% and protein minimum value 2.7%. The sensory acceptability of the YM and the YB was high, with 88.9% and 94.7%, respectively. During storage under accelerated conditions, pH decreased to 3.88 and 3.92; titrable acidity i...
11
artículo
The aim this work was to compare the extraction process optimization of total glucosinolates of maca flour (Lepidium meyenii) (ETGMF) using RS for Box-Behnken (RSBB) Design with that of GA, according to x1: temperature (°C), x2: ethanol (%), x3: ratio solvent/raw material and x4: extraction time (min). TG were identified and quantified using HPLC. The variables (x1, x2, x3, x4) that influence their extraction were evaluated using a RSBB with the software Statistica and Wolfram Mathematica for the AG. From the development of the RSBB, a second order equation with R2 = 0.74794, p = 1.88248E-10 << 0.05 with 11% average absolute error was obtained; it showed the consistency of the model. It was not possible to obtain an optimal value of the ETGMF using RSBB because of the existence of two optimal zones due to the configuration of a chair surface. After 2000 iterations using GA, the ma...
12
artículo
A bi-factorial experimental design was considered to assess moisture variation of sweet potato-quinoa-kiwicha flakes (SP-Q-K) caused by the changes in the rotational speed and steam pressure of a rotary drum dryer (RDD). As it is a design with discrete variables, there is a limitation in the modeling and optimization thus techniques of Artificial Intelligence (AI): Artificial Neural Networks (ANN), Fuzzy Logic (FL) and Genetic Algorithms (GA), were applied, and their prediction ability evaluated. Due to the limitation of data for proper training, the ANN did not allow a correct prediction of the experimental data. Response Surface Methodology (RSM) was employed to obtain the relational equation among the experimental variables, which was used as the objective function with GA, and this allowed moisture optimization. Because of this, it is recommended to integrate RSM and GA into optimiza...
13
artículo
Se evaluó la digestibilidad proteica aparente (DA) de harina y soluciones de harina de “garbanzo”(GD) Cicer arietinum L. in vivo empleando “ratones albinos” de laboratorio (Mus musculus BALB/C)e in vitro empleando Saccharomyces cerevisiae (Saccharomycetaceae) como organismo modelo,utilizando el medio YPD (extracto de levadura, peptona, dextrosa) a pH 5.8 como control. Losmedios GD fueron preparados con y sin enzima ajustada a valores de pH de 5.8, 5.5, 4.6, 3.8, 2.8, 2.3Y 2.0. El organismo modelo fue sembrado en placas Petri con medios YDP y GD, incubado a 30ºCpor 24 h. Se utilizó ratones en 5 grupos de trabajo con 2 especímenes por grupo, alimentados condietas a base de avena comercial, harina de maíz y 4, 8, 12% de harina de “garbanzo”. Se suministróuna ración de 20 g/d durante 15 días, al final se recogieron las heces y se determinó el contenido denitrógeno y pro...
14
artículo
Se evaluó la digestibilidad proteica aparente (DA) de harina y soluciones de harina de “garbanzo”(GD) Cicer arietinum L. in vivo empleando “ratones albinos” de laboratorio (Mus musculus BALB/C)e in vitro empleando Saccharomyces cerevisiae (Saccharomycetaceae) como organismo modelo,utilizando el medio YPD (extracto de levadura, peptona, dextrosa) a pH 5.8 como control. Losmedios GD fueron preparados con y sin enzima ajustada a valores de pH de 5.8, 5.5, 4.6, 3.8, 2.8, 2.3Y 2.0. El organismo modelo fue sembrado en placas Petri con medios YDP y GD, incubado a 30ºCpor 24 h. Se utilizó ratones en 5 grupos de trabajo con 2 especímenes por grupo, alimentados condietas a base de avena comercial, harina de maíz y 4, 8, 12% de harina de “garbanzo”. Se suministróuna ración de 20 g/d durante 15 días, al final se recogieron las heces y se determinó el contenido denitrógeno y pro...
15
artículo
Se implementó un sistema de control automático por lógica difusa de oxígeno disuelto (OD), pH y temperatura en un biorreactor columna de burbujas (BCB), para la producción de biomasa de Candida utilis CECT 10704. Su desempeño se comparó con el control proporcional clásico. Para el control se diseñó, construyó y programó una tarjeta de adquisición de datos, utilizando el software Eagle 4.14 para el diseño y Microcode Studio Plus 3.0 para la programación. Se elaboró un programa en Visual Basic 6.0, que enlazó con MatLab 7.0 para el control difuso; utilizando la inferencia Mandani, funciones de membresia de entrada y salida trapezoidal y triangular; 4 reglas para el OD, 3 para el pH y 3 para la temperatura; con conector tipo and y para desdifusificar el método del centroide. La evaluación de la producción de biomasa se realizó mediante la determinación de peso seco y c...
16
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The predictive ability of Artificial Neural Network (ANN) on the effect of the concentration (30, 40, 50 y 60 % w/w) and temperature (30, 40 y 50°C) of fructooligosaccharides solution, in the mass, moisture, volume and solids of osmodehydrated yacon cubes, and in the coefficients of the water means effective diffusivity with and without shrinkage was evaluated. The Feedforward type ANN with the Backpropagation training algorithms and the Levenberg-Marquardt weight adjustment was applied, using the following topology: 10-5 goal error, 0.01 learning rate, 0.5 moment coefficient, 2 input neurons, 6 output neurons, one hidden layer with 18 neurons, 15 training stages and logsig-pureline transfer functions. The overall average error achieved by the ANN was 3.44% and correlation coefficients were bigger than 0.9. No significant differences were found between the experimental values and the pr...
17
artículo
Potato is grown and consumed throughout the world for their particular calorific nutritional value and vitamin C, but it also contains phytochemicals (secondary metabolites) that have been studied and found to have positive effects in preventing degenerative diseases in human health, such as hypertensive activity, and also atherosclerosis, type 2 diabetes, liver fibrosis, Alzheimer's disease, macular degeneration and cancer. We aimed to identify and quantify phenolic compounds in potatoes grown on El Zuro (EZ) and Huayatan Alto (HA) in Santiago de Chuco, La Libertad, Peru. The field trials were carried out in EZ (altitude 3750 m.a.s.l.) and HA (altitude 3150 m.a.s.l.) employing organic and inorganic fertilization respectively. Extraction from the peel and flesh was obtained separately, with the following solution: 50% methanol, 50% deionized water and 0.5% acetic acid. The sample was inj...
18
artículo
Se implementó un sistema de control automático por lógica difusa de oxígeno disuelto (OD), pH y temperatura en un biorreactor columna de burbujas (BCB), para la producción de biomasa de Candida utilis CECT 10704. Su desempeño se comparó con el control proporcional clásico. Para el control se diseñó, construyó y programó una tarjeta de adquisición de datos, utilizando el software Eagle 4.14 para el diseño y Microcode Studio Plus 3.0 para la programación. Se elaboró un programa en Visual Basic 6.0, que enlazó con MatLab 7.0 para el control difuso; utilizando la inferencia Mandani, funciones de membresia de entrada y salida trapezoidal y triangular; 4 reglas para el OD, 3 para el pH y 3 para la temperatura; con conector tipo and y para desdifusificar el método del centroide. La evaluación de la producción de biomasa se realizó mediante la determinación de peso seco y c...
19
artículo
The predictive ability of Artificial Neural Network (ANN) on the effect of the concentration (30, 40, 50 y 60 % w/w) and temperature (30, 40 y 50°C) of fructooligosaccharides solution, in the mass, moisture, volume and solids of osmodehydrated yacon cubes, and in the coefficients of the water means effective diffusivity with and without shrinkage was evaluated. The Feedforward type ANN with the Backpropagation training algorithms and the Levenberg-Marquardt weight adjustment was applied, using the following topology: 10-5 goal error, 0.01 learning rate, 0.5 moment coefficient, 2 input neurons, 6 output neurons, one hidden layer with 18 neurons, 15 training stages and logsig-pureline transfer functions. The overall average error achieved by the ANN was 3.44% and correlation coefficients were bigger than 0.9. No significant differences were found between the experimental values and the pr...
20
artículo
Potato is grown and consumed throughout the world for their particular calorific nutritional value and vitamin C, but it also contains phytochemicals (secondary metabolites) that have been studied and found to have positive effects in preventing degenerative diseases in human health, such as hypertensive activity, and also atherosclerosis, type 2 diabetes, liver fibrosis, Alzheimer's disease, macular degeneration and cancer. We aimed to identify and quantify phenolic compounds in potatoes grown on El Zuro (EZ) and Huayatan Alto (HA) in Santiago de Chuco, La Libertad, Peru. The field trials were carried out in EZ (altitude 3750 m.a.s.l.) and HA (altitude 3150 m.a.s.l.) employing organic and inorganic fertilization respectively. Extraction from the peel and flesh was obtained separately, with the following solution: 50% methanol, 50% deionized water and 0.5% acetic acid. The sample was inj...