338 research outputs found
Water Sorption of Amaranthus cruentus L. Seeds Modelled by GAB Equation
The GAB (Guggenheim, Andersen, and de Boer) equation was adjusted to literature data of sorption of Amarunthus cruentus L. (Me vs. a w for adsorption and desorption) determined at 25,30, 35,40,45, 50, 55,65,70, and 90°C, in the range of water activity from 0.029 to 0.979. To quantify the goodness of fit, the correlation coefficient (R2), the sum of squares (RSS), the standard error of the estimate (Sy), the mean relative deviation (MRD) and the plots of residuals were analysed. The three theoretical parameters of the GAB model (Mo, C, and K) gave a good correlation (R2 > 0.9817, RSS < 0.0297, MRD < 0.138, Sy < 0.0143, and random residuals-plots) in the range of a w from 0.029 to 0.979, of interest in seed storage and processing. However this correlation does not consider the effect of temperature (T) on coefficient values. In a second stage, parameters Mo and K were adjusted at each temperature. Very low variances were obtained in the range 25-65°C for desorption and in the range 25-55°C for adsorption. These results suggested that Mo and K remain almost constant and a correlation with T is not justified. On the contrary sense, parameter C showed stronger variation with T. This was explained by the analysis of sensitivity for the influence of C on moisture content. On this basis, the relation C-T was proposed by an Arrhenius-type relation [C=A.exp(B/T)] and this function was incorporated to the original GAB model to re-estimate the parameters A, B, Mo, and K. The developed modification provides a generalised and precise expression of GAB model for Amaranth.Centro de Investigación y Desarrollo en Criotecnología de Alimento
A multi-criteria optimization and decision-making approach for improvement of food engineering processes
The objective of this study was to propose a multi-criteria optimization and decision-making technique to solve food engineering problems. This technique was demonstrated using experimental data obtained on osmotic dehydration of carrot cubes in a sodium chloride solution. The Aggregating Functions Approach, the Adaptive Random Search Algorithm, and the Penalty Functions Approach were used in this study to compute the initial set of non-dominated or Pareto-optimal solutions. Multiple non-linear regression analysis was performed on a set of experimental data in order to obtain particular multi-objective functions (responses), namely water loss, solute gain, rehydration ratio, three different colour criteria of rehydrated product, and sensory evaluation (organoleptic quality). Two multi-criteria decision-making approaches, the Analytic Hierarchy Process (AHP) and the Tabular Method (TM), were used simultaneously to choose the best alternative among the set of non-dominated solutions. The multi-criteria optimization and decision-making technique proposed in this study can facilitate the assessment of criteria weights, giving rise to a fairer, more consistent, and adequate final compromised solution or food process. This technique can be useful to food scientists in research and education, as well as to engineers involved in the improvement of a variety of food engineering processes.Facultad de IngenieríaCentro de Investigación y Desarrollo en Criotecnología de Alimento
A multi-criteria optimization and decision-making approach for improvement of food engineering processes
The objective of this study was to propose a multi-criteria optimization and decision-making technique to solve food engineering problems. This technique was demonstrated using experimental data obtained on osmotic dehydration of carrot cubes in a sodium chloride solution. The Aggregating Functions Approach, the Adaptive Random Search Algorithm, and the Penalty Functions Approach were used in this study to compute the initial set of non-dominated or Pareto-optimal solutions. Multiple non-linear regression analysis was performed on a set of experimental data in order to obtain particular multi-objective functions (responses), namely water loss, solute gain, rehydration ratio, three different colour criteria of rehydrated product, and sensory evaluation (organoleptic quality). Two multi-criteria decision-making approaches, the Analytic Hierarchy Process (AHP) and the Tabular Method (TM), were used simultaneously to choose the best alternative among the set of non-dominated solutions. The multi-criteria optimization and decision-making technique proposed in this study can facilitate the assessment of criteria weights, giving rise to a fairer, more consistent, and adequate final compromised solution or food process. This technique can be useful to food scientists in research and education, as well as to engineers involved in the improvement of a variety of food engineering processes.Facultad de IngenieríaCentro de Investigación y Desarrollo en Criotecnología de Alimento
Estudio comparativo de la congelación de papa (Solanum tuberosum L.) sometida a diferentes pretratamientos
Se estudió la historia térmica del proceso de congelación de papas frescas y pretratadas por los siguientes tratamientos: deshidratación osmótica, por escaldado y posterior microondas y deshidratación osmótica seguida de microondas. Las papas pretratadas disminuyen su contenido de agua durante los diferentes procesos y por consiguiente, el posterior proceso de congelación requiere tiempos de congelación menores y de esta manera se pueden lograr ahorros energéticos importantes. Los tiempos de congelación se estimaron muy satisfactoriamente aplicando la ecuación de Salvadori-Mascheroni y se compararon con los experimentales. Los errores son inferiores al 8%. Las papas pretratadas por deshidratación osmótica y microondas exhibieron un tiempo de congelación 9 minutos inferior al de las papas frescas.The thermal history of freezing fresh and pre-treated potatoes was studied by the following treatments: osmotic dehydration, scald and later microwave and osmotic dehydration followed by microwave. Pre-treated potatoes reduce its water content during the different processes and therefore the subsequent process of freezing requires lower freezing times and in this way, significant energy savings can be achieved. The freezing times were estimated very satisfactorily by applying the equation of Salvadori - Mascheroni and were compared with the experimental ones. The errors are lower than 8%. Pre-treated potatoes by osmodehydration and then microwave exhibit a freezing time 9 minutes lower than the fresh potatoes one.Fil: Della Rocca, Patricia A.. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; ArgentinaFil: Roche, Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigaciones en Criotecnología de Alimentos (i); Argentina. Universidad Nacional de La Plata; ArgentinaFil: Mascheroni, Rodolfo Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigaciones en Criotecnología de Alimentos (i); Argentina. Universidad Nacional de La Plata; Argentin
Rapid Releases and Testing Problems at the industry: A survey
Rapid releases and continuous software development are established practices in modern agile projects. The advantages of them are widely known across the software development community, but there are some studies which mention that there are still challenges to face. According to them, there are different open issues which are affecting the implementation of an adequate testing process. With the aim of validating if these problems are present in real projects, in this paper we present the results of a survey whose goal was to validate whether the industry is experiencing similar issues and their causes.
The findings demonstrate that both the industry and academic side are aligned, and that there is still a need for processes and tools regarding the testing process in continuous development.XVI Workshop Ingeniería de Software.Red de Universidades con Carreras en Informátic
Rapid Releases and Testing Problems at the industry: A survey
Rapid releases and continuous software development are established practices in modern agile projects. The advantages of them are widely known across the software development community, but there are some studies which mention that there are still challenges to face. According to them, there are different open issues which are affecting the implementation of an adequate testing process. With the aim of validating if these problems are present in real projects, in this paper we present the results of a survey whose goal was to validate whether the industry is experiencing similar issues and their causes.
The findings demonstrate that both the industry and academic side are aligned, and that there is still a need for processes and tools regarding the testing process in continuous development.XVI Workshop Ingeniería de Software.Red de Universidades con Carreras en Informátic
Estudio de la transferencia de agua durante la deshidratación osmótica de zanahoria
Se estudió la cinética de deshidratación y la ganancia de sólidos de cubos de zanahoria en solución de sacarosa y sal a una temperatura de 40 °C. Se aplicaron modelos empíricos para describir el proceso de transferencia de agua desde el alimento hacia la solución como los de Azuara, Page y uno teórico, basado en la segunda ley de difusión de Fick, el modelo de Crank. Todos ajustaron los datos experimentales de manera satisfactoria, siendo los dos primeros los que presentaron un mejor ajuste. Se estimó el coeficiente de difusión efectiva del agua y el valor obtenido fue de aproximadamente 1,5x10-9 m2 /s, similar a los hallados en la literatura en condiciones análogas.The osmotic dehydration kinetic and the solid uptake of carrots cubes in a sucrose-salt solution at a temperature of 40 °C were studied. Empiric models were applied to describe the process of water transfer from the product to the solution. All the models: Azuara, Page and Crank adjust the experimental data in a satisfactory way, being the two first models which adjust better. The water diffusion effective coefficient was estimated and the value obtained was 1,5x 10-9 m2 /s, similar to that found in the literature in analogous conditions.Fil: Della Rocca, Patricia A.. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; ArgentinaFil: Roche, Luis Alberto. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigaciones en Criotecnología de Alimentos (i); Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas; ArgentinaFil: Mascheroni, Rodolfo Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigaciones en Criotecnología de Alimentos (i); Argentina. Universidad Nacional de La Plata; Argentin
Rapid Releases and Testing Problems at the industry: A survey
Rapid releases and continuous software development are established practices in modern agile projects. The advantages of them are widely known across the software development community, but there are some studies which mention that there are still challenges to face. According to them, there are different open issues which are affecting the implementation of an adequate testing process. With the aim of validating if these problems are present in real projects, in this paper we present the results of a survey whose goal was to validate whether the industry is experiencing similar issues and their causes.
The findings demonstrate that both the industry and academic side are aligned, and that there is still a need for processes and tools regarding the testing process in continuous development.XVI Workshop Ingeniería de Software.Red de Universidades con Carreras en Informátic
Comparison of two alternatives of combined drying to process blueberries (O'Neal): evaluation of the final quality
In this work, we examined and compared two combined alternatives for the drying of blueberries (O´Neal). Pretreatments of osmotic dehydration (60°Brix sucrose solution, at 40°C for 6h) and hot air drying (60°C, 2.5 m/s for 90 min) were performed to reach the same water content. Pretreated blueberries were then dried by microwave at different microwave output power values: 562.5W, 622.5W and 750W. The combined drying processes were also compared with hot air drying alone (control). The effects of the processes over blueberries were studied in terms of decrease in water content, drying rate, mechanical properties (firmness and stiffness), optical properties (L*, a* and hue angle (h)), antioxidant capacity and rehydration capacity. The hot air-microwave drying decreased the process time and presented a high drying rate compared with the osmotic dehydration-microwave processes and the control drying. In terms of quality, the antioxidant and rehydration capacities were the most affected. The results showed that the best drying method to obtain the desired final product was the hot air-microwave drying (750W).Fil: Rodriguez, A.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigaciones En Criotecnología de Alimentos (i); Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas; ArgentinaFil: Zaro, Maria Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigaciones En Criotecnología de Alimentos (i); Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas; ArgentinaFil: Lemoine, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigaciones En Criotecnología de Alimentos (i); Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Mascheroni, Rodolfo Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigaciones En Criotecnología de Alimentos (i); Argentina. Universidad Nacional de La Plata. Facultad de Ingenieria; Argentin
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