A new method for designing optimum package size and processing conditions for re-tortable flexible or microwaveable packages has been specified. The method employed the random centroid optimization technique. The method also included a computer simulation model, used to calculated process lethality and nutrient degradation, and an objective function used to calculate total process cost from the above values as well as from the processing parameters. The objective function was original in that it was economicaly based, rather than concentrating solely on achieving processes with high product quality. Typical processing costs such as the cost of energy or materials were included, as well as more qualitative costs such as those associated with decreases in product quality. Most of these costs were inferred from conventional can processing costs, as information regarding processing costs for flexible or microwaveable retortable packages was often unavailable. For the simulation model, a recently developed one dimensional finite difference technique of high accuracy (the exponential finite difference method) was extended to three dimensions and used to solve the partial differential heat flow equation. The simulation model also comprised an original algorithm to model headspace and a new numerical integration technique to calculate lethality and nutrient degradation from the time temperature profile. The headspace model calculated headspace volume as a function of retort temperature and pressure and then used steady state heat transfer theory to model heat flow across the package headspace. The numerical integration technique fitted an exponential curve to the time temperature profile and then integrated this curve analytically. The accuracies of the exponential finite difference method with and without headspace included and of the numerical integration technique were tested by comparison with both analytical solutions and other well established numerical methods. In addition, the uncertainty associated with the assumption of uniform paramaters was evaluated using a Monte Carlo technique. After the validity of the simulation model was established, it was used in conjunction with the objective function and the random centroid optimization method to search for a global cost minimum. One trial optimization using a simple objective function was made, followed by three optimization runs using the more complex objective function desinged to calculate process cost. Each optimization used a different set of decision variables, which varied in number from three to five. The results were evaluated as to whether a minimum was found, and if so, whether it constituted a global minimum. / Science, Faculty of / Botany, Department of / Zoology, Department of / Graduate

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En el presente documento se presentará un proyecto innovador como una posible solución ante la crisis actualmente vivida por el virus Covid 20. El proyecto tiene como nombre “CleanBox”, el cual es una caja esterilizadora cuyas dimensiones son perfectas para colocar productos tanto pequeños como medianos. Asimismo, con Cleanbox, se pueden esterilizar productos, tales como frutas, verduras, entre otros. Además, el modo de uso del aparato es muy sencillo y cualquier persona de la familia puede utilizarla. Este proyecto tiene como finalidad tratar de proteger la salud de los clientes, mediante la reducción de la propagación del virus con la esterilización de los productos que usualmente usa o compra en la calle y pueden estar contaminados. En este caso, nos dirigimos a hombres y mujeres entre los 30 y 55 años del nivel socioeconómico A y B, ya que estos son más sensibles en temas de proteger su salud y la de su familia, buscando alternativas que les ofrezcan resultados eficientes y rápidos. Debido a la crisis coyuntural internacional que actualmente vivimos, el proyecto, de manera momentánea, se enfocará solamente en Lima metropolitana y Callao. También, siguiendo las aperturas permitidas por el gobierno, se irá expandiendo el envío del producto, es decir, se logrará hacer envíos a diferentes provincias del Perú y pensar en la externalización del producto. / In this document an innovative project will be presented as a possible solution to the currently crisis that was experienced by the Covid 20 virus. The project is called “CleanBox”, which is a sterilizing box whose dimensions are perfect for placing both small and medium-sized products. Likewise, with Cleanbox, products can be sterilized, whether from an electronic device to perishable products. In addition, the way to use the device is very simple and anyone in the family can use it. This project aims to try to protect the health of customers, by reducing the spread of the virus with the sterilization of products that you usually use or buy on the street and may be contaminated. In this case, we are targeting men and women between the ages from 30 to 55 of A and B socioeconomic levels, since they are more sensitive in terms of protecting their health and that of their family, looking for alternatives that offer them efficient and quick results. . Due to the international economic crisis that we are currently experiencing, the project, momentarily, will focus only on metropolitan Lima and Callao. Also, following the openings allowed by the government, the shipment of the product will be expanded, that is, it will be possible to make shipments to different provinces of Peru and think about outsourcing the product. / Trabajo de investigación

Células transformadas de E.coli DH5-&#945; expressando a proteína verde fluorescente (GFPuv, pico de excitação e emissão de 394nm e 509nm) foram submetidas a extração pelo método de partição de três fases (TPP) e o extrato obtido purificado por cromatografia de interação hidrofóbica (HIC). O objetivo principal deste trabalho foi estudar a termoestabilidade da GFPuv extraída, para avaliar a sua possível utilização como indicador biológico econômico, de resposta rápida e precisa para processos térmicos de esterilização utilizando o calor úmido. A estabilidade térmica da proteína foi estudada em diferentes soluções-tampão (acetato, fosfato e tris-HCI 10mM) no intervalo de valor de pH de 5,O a 9,0 e, em temperaturas entre 75&#176; e 95&#176;C. Os parâmetros de resistência térmica determinados foram: o tempo de redução decimal (Valor D - min), valor z (&#176;C), coeficiente Q10 e valor de energia de ativação (kcal/mol). A termoestabilidade da GFPuv, expressa em valor D, mostrou correlação linear para valores de pH &#8805; 5,50, em tampão acetato. Em tampão fosfato, para valores de pH &#8805; 7,50 a estabilidade térmica da proteína foi independente do valor de pH da solução. Em tampão tris-HCI, o valor D mostrou-se inconstante ao aumento do valor de pH da solução. No intervalo de temperatura estudada, em tampão acetato a GFPuv apresentou melhor termoestabilidade (Ea de 19,27 kcal/mol) do que em tampão fosfato (Ea de 26,18 kcal/mol ao valor de pH 6,S) e em tampão tris-HCI (Ea 28,19 kcallmol ao valor de pH 7,0). Em tampão acetato e tris-HCI ao valor de pH 7,0, a termoestabilidade da proteína mostrou-se equivalente. Entretanto, em tampão fosfato aos valores de pH 7,5 e 8,0 e em tampão tris-HCI aos valores de pH 8,0 e 8,5 a GFPuv apresentou menor estabilidade térmica A GFPuv apresenta potencialidade para ser utilizada como indicador biológico em processos térmicos que utilizam calor úmido às temperaturas inferiores a 100°C. / Transformed cells of Escheríchía coli DH5-&#945; expressing recombinant green fluorescent protein (GFPuv, excitation and emission peaks at 394nm and 509nm), were subjected to the three-phase partitioning (TPP) method and the release extracts were eluted through methyl HIC column with a buffer solution (10 mM Tris-HCI, 10mM EDTA, pH=8.0). The purpose of this work was to study the thermal stability of the TPP-extracted recombinant protein, GFPuv, to determine its utility as a quick, accurate and economical biological indicator for moist heat-treatments. The thermal stability of the extracted GFPuv was studied in different buffer solutions (acetate, phosphate and tris-HCI 10mM) in the range of pH between 5.0 and 9.0 and at temperature between 75-95°C. The thermal resistance parameters determinated were: decimal reduction times (D-values, min), z-value (&#1776C), Q<sub<10 coefficient and Activation Energy (Ea, Kcal/mol). The thermal stability of GFPuv, expressed in D-values, showed linear correlation for pH &#8805; 5.50 in acetate buffer. In phosphate buffer, for pH &#8805; 7.50 the thermal stability was independent of pH value. In tris-HCI buffer the D-value was shown variable with the increase of pH value. In the studied temperature range, the acetate buffer at pH 6.0 presented better thermal stability for GFPuv (Ea 19.27kcal/mol) than phosphate (Ea 26.18 kcal/mol at pH 6.5) and tris-HCI buffer (Ea 28.19 kcal/mol at pH 7.0). In acetate and tris-HCI buffers at pH 7.0, GFPuv showed equivalent thermal stability. However, GFPuv showed lower thermal stability in phosphate buffer at pH 7.5 and 8.0 and in tris-HCI buffer at pH 8.0 and 8.5. The TPP-extracted GFPuv has great potential to be applied as a biological indicator in moist heat processes at temperatures below 100°C.

Células transformadas de E.coli DH5-&#945; expressando a proteína verde fluorescente (GFPuv, pico de excitação e emissão de 394nm e 509nm) foram submetidas a extração pelo método de partição de três fases (TPP) e o extrato obtido purificado por cromatografia de interação hidrofóbica (HIC). O objetivo principal deste trabalho foi estudar a termoestabilidade da GFPuv extraída, para avaliar a sua possível utilização como indicador biológico econômico, de resposta rápida e precisa para processos térmicos de esterilização utilizando o calor úmido. A estabilidade térmica da proteína foi estudada em diferentes soluções-tampão (acetato, fosfato e tris-HCI 10mM) no intervalo de valor de pH de 5,O a 9,0 e, em temperaturas entre 75&#176; e 95&#176;C. Os parâmetros de resistência térmica determinados foram: o tempo de redução decimal (Valor D - min), valor z (&#176;C), coeficiente Q10 e valor de energia de ativação (kcal/mol). A termoestabilidade da GFPuv, expressa em valor D, mostrou correlação linear para valores de pH &#8805; 5,50, em tampão acetato. Em tampão fosfato, para valores de pH &#8805; 7,50 a estabilidade térmica da proteína foi independente do valor de pH da solução. Em tampão tris-HCI, o valor D mostrou-se inconstante ao aumento do valor de pH da solução. No intervalo de temperatura estudada, em tampão acetato a GFPuv apresentou melhor termoestabilidade (Ea de 19,27 kcal/mol) do que em tampão fosfato (Ea de 26,18 kcal/mol ao valor de pH 6,S) e em tampão tris-HCI (Ea 28,19 kcallmol ao valor de pH 7,0). Em tampão acetato e tris-HCI ao valor de pH 7,0, a termoestabilidade da proteína mostrou-se equivalente. Entretanto, em tampão fosfato aos valores de pH 7,5 e 8,0 e em tampão tris-HCI aos valores de pH 8,0 e 8,5 a GFPuv apresentou menor estabilidade térmica A GFPuv apresenta potencialidade para ser utilizada como indicador biológico em processos térmicos que utilizam calor úmido às temperaturas inferiores a 100°C. / Transformed cells of Escheríchía coli DH5-&#945; expressing recombinant green fluorescent protein (GFPuv, excitation and emission peaks at 394nm and 509nm), were subjected to the three-phase partitioning (TPP) method and the release extracts were eluted through methyl HIC column with a buffer solution (10 mM Tris-HCI, 10mM EDTA, pH=8.0). The purpose of this work was to study the thermal stability of the TPP-extracted recombinant protein, GFPuv, to determine its utility as a quick, accurate and economical biological indicator for moist heat-treatments. The thermal stability of the extracted GFPuv was studied in different buffer solutions (acetate, phosphate and tris-HCI 10mM) in the range of pH between 5.0 and 9.0 and at temperature between 75-95°C. The thermal resistance parameters determinated were: decimal reduction times (D-values, min), z-value (&#1776C), Q<sub<10 coefficient and Activation Energy (Ea, Kcal/mol). The thermal stability of GFPuv, expressed in D-values, showed linear correlation for pH &#8805; 5.50 in acetate buffer. In phosphate buffer, for pH &#8805; 7.50 the thermal stability was independent of pH value. In tris-HCI buffer the D-value was shown variable with the increase of pH value. In the studied temperature range, the acetate buffer at pH 6.0 presented better thermal stability for GFPuv (Ea 19.27kcal/mol) than phosphate (Ea 26.18 kcal/mol at pH 6.5) and tris-HCI buffer (Ea 28.19 kcal/mol at pH 7.0). In acetate and tris-HCI buffers at pH 7.0, GFPuv showed equivalent thermal stability. However, GFPuv showed lower thermal stability in phosphate buffer at pH 7.5 and 8.0 and in tris-HCI buffer at pH 8.0 and 8.5. The TPP-extracted GFPuv has great potential to be applied as a biological indicator in moist heat processes at temperatures below 100°C.