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The global coconut water market is projected to grow in the upcoming years, attributed to its numerous health benefits. However, due to its susceptibility to microbial contamination and the limitations of non-thermal decontamination methods, thermal treatments remain the primary approach to ensure the shelf-life stability and the microbiological safety of the product. In this study, the thermal inactivation of Listeria innocua, a Listeria monocytogenes surrogate, was evaluated in coconut water and in tryptone soy broth (TSB) under both isothermal (50–60 C) and dynamic conditions (from 30 to 60 C, with temperature increases of 0.5, 1 and 5 C/min). Mathematical models were used to analyse the inactivation data. The Geeraerd model effectively described the thermal inactivation of L. innocua in both TSB and coconut water under isothermal conditions, with close agreement between experimental data and model fits. Parameter estimates and analysis revealed that acidified TSB is a suitable surrogate medium for studying the thermal inactivation of L. innocua in coconut water, despite minor differences observed in the shoulder length of inactivation curves, likely attributed to the media composition. The models fitted to the data obtained at isothermal conditions fail to predict L. innocua responses under dynamic conditions. This is attributed to the stress acclimation phenomenon that takes place under dynamic conditions, where bacterial cells adapt to initial sub-lethal treatment stages, leading to increased thermal resistance. Fitting the Bigelow model directly to dynamic data with fixed z-values reveals a three-fold increase in D-values with lower heating rates, supporting the role of stress acclimation. The findings of this study aid in designing pasteurization treatments targeting L. innocua in coconut water and enable the establishment of safe, mild heat treatments for refrigerated, high-quality coconut water.

[SPA] La evaluación de riesgos microbianos es crucial para proteger la salud pública, así como para que la cadena de suministro de alimentos sea eficiente. La evaluación debe considerar varias fuentes variabilidad en la respuesta microbiana, tales como la adaptación al estrés y las heterogeneidades genéticas, ya que éstas pueden afectar la supervivencia, el crecimiento y la virulencia de los patógenos alimentarios influyendo a su capacidad para causar enfermedades en humanos o alteraciones en los alimentarios. Actualmente existen grandes lagunas de conocimiento en cuanto a la variabilidad de la respuesta microbiana, por lo que su elucidación es esencial para una estimación precisa del riesgo, así como para el desarrollo de medidas de control eficaces. En base a esto, esta tesis de doctorado tiene como objetivo evaluar y comparar la importancia de la adaptación al estrés y las heterogeneidades genéticas en los microorganismos para la supervivencia de las bacterias a los tratamientos térmicos. En el Capítulo I se estudia la inactivación térmica de dos cepas de Salmonella (Salmonela Enteritidis CECT4300 y Senftenberg CECT4565) tanto en condiciones isotérmicas como dinámicas. Para los tratamientos isotérmicos, se encontró que S. Senftenberg era mucho más resistente que S. Enteritidis (por un factor de aproximadamente 10). También observamos diferencias cualitativas: las curvas de supervivencia isotermas de la cepa de S. Senftenberg fueron de tipo Weibull, mientras que el modelo Bigelow (lineal) fue capaz de describir la respuesta de S. Enteritidis. Así mismo, los modelos basados en experimentos isotérmicos fueron capaces de describir la inactivación dinámica de S. Senftenberg, mientras que S. Enteritidis necesitó de un modelo dinámico que consideraba la aclimatación del estrés. El estudio destaca que, además de la variabilidad cuantitativa, la inactividad microbiana también tiene una componente cualitativa. Esto enfatiza la importancia de considerar diferentes hipótesis

[SPA] Esta tesis doctoral se presenta bajo la modalidad de compendio de publicaciones. Existe un interés creciente en la modelización matemática para afrontar los problemas cada vez más complejos a los que se enfrentan las industrias alimentarias con el objetivo de asegurar tanto la calidad como la seguridad de los alimentos. Si bien la cantidad de datos disponibles ha experimentado un aumento extraordinario en las últimas décadas, su complejidad no permite, en muchas ocasiones, el uso de herramientas convencionales de análisis. Por ello, es esencial el desarrollo de una nueva generación de herramientas matemáticas que puedan implementarse en el ámbito de los procesos alimentarios de forma eficiente, cuyos resultados sean accesibles a los responsables de la toma de decisiones para poder avanzar hacia la producción de alimentos de mayor calidad y más seguros. En esta tesis doctoral se desarrollan herramientas de modelización aplicadas a la seguridad alimentaria desde el punto de vista microbiológico y toxicológico. Se proponen nuevas estrategias y técnicas que combinan las ya existentes con el fin de generar directrices y pautas para ser utilizadas en la toma de decisiones por parte de los agentes implicados en relación con la seguridad y calidad alimentaria. Las herramientas propuestas comprenden diferentes metodologías como la modelización, la simulación y el análisis de procesos de inactivación microbiana, así como métodos de estadística aplicada y de investigación operativa para optimizar procesos y diseñar experimentos que permitan mejorar la precisión de los modelos matemáticos. La tesis se basa en cuatro de los artículos publicados en este periodo de formación. Los dos primeros tratan sobre diseño óptimo de experimentos en microbiología predictiva haciendo una diferenciación entre experimentos isotermos y no isotermos (dinámicos). Se concluyen con unas pautas y consejos para la toma de decisiones en relación a cómo diseñar los experimentos con el fin de maximi, [ENG] This doctoral dissertation has been presented in the form of thesis by publication. There is a growing interest in mathematical modeling to address the increasingly complex problems faced by food industries in order to ensure both food quality and safety. Although the amount of available data has experienced an extraordinary increase in the last decades, its complexity does not allow, on many occasions, the use of conventional analysis tools. Therefore, it is essential to develop a new generation of mathematical tools that can be implemented in the field of food processes in an efficient way, whose results are accessible to decision-makers in order to move towards the production of higher quality and safer food. In this doctoral thesis, modeling tools applied to food safety from a microbiological and toxicological point of view are developed. New strategies and techniques are proposed that combine the existing ones to generate guidelines and recommendations to be used in decision-making by stakeholders involved in food safety and quality. The proposed tools are framed within different scientific and engineering fields, such as modeling, simulation and analysis of microbial inactivation processes, as well as methods of applied statistics and operational research to optimize processes and designs of experiments that improve the accuracy of mathematical models. The thesis is based on four of the papers published during this training period. The first two deal with the optimal design of experiments in predictive microbiology distinguishing between isothermal and non-isothermal (dynamic) experiments. They conclude with some guidelines and advice for decision-making concerning how to design the experiments to maximize the information obtained from them. On the other hand, the second block of publications deals with food safety from the abiotic point of view. In particular, the production of acrylamide in heat treatments and its relationship with other quality and sa

This study uncovered the impacts of microwave (MW) treatments compared to conventional pasteurization (TP) on the quality of functional citrus–maqui beverages, with added sucrose or stevia. The influence of these thermal treatments on the microbiological burden and phytochemical composition was determined by processing under two MW power levels (600 W and 800 W) and TP at 85 °C for 15 s for 60 days at room temperature (20 °C). The results indicated that, beyond the microbiological quality achieved in the juices treated by both MW and TP technology, there were no differences among the treatments regarding the stability of vitamin C, anthocyanin, and flavanone concentrations. However, anthocyanins were more stable in those beverages with sucrose added, rendering a better red color. Besides, all treatments ensured microbiological stability throughout the entire storage time. In conclusion, MW treatment could be considered as an alternative to TP, which ensures microbial safety, protecting functional compounds associated with health effects.

[SPA] Listeria monocytogenes es una de las bacterias patógenas más comunes que pueden encontrarse en los alimentos porque puede adaptarse muy bien a factores estresantes como temperaturas bajas o pH ácidos. Las verduras envasadas, la leche sin pasteurizar, el queso y los productos cárnicos son los alimentos en los que se puede encontrar. La mayoría de estos productos están expuestos a tratamientos térmicos para asegurar su conservación. En algunas circunstancias, esta bacteria puede aumentar su resistencia térmica, si se trata a temperaturas subletales. El objetivo de esta investigación fue seleccionar poblaciones de L. monocytogenes resistentes al calor tras aplicar tratamientos térmicos prolongados a temperaturas de tratamiento bajas (1 hora a 55°C) y tratamientos térmicos cortos a temperaturas altas (1 minuto a 65°C). Los resultados obtenidos muestran que el microorganismo es capaz de aumentar su resistencia al calor en ambas situaciones, tras ciclos sucesivos de tratamiento térmico y crecimiento. [ENG] Listeria monocytogenes is one of the most common foodborne pathogenic bacteria. It can adapt very well to stressors such as low temperatures or acidic pH. It is mostly found in food product like packaged vegetables, raw milk, cheese, and meat products. Most of these food products undergo a heat treatment to ensure preservation. In some circumstances, this bacterium can increase its heat resistance, if treated at sub-lethal temperatures. The aim of this study was to select heat-resistant populations of L. monocytogenes after prolonged heat treatments: long heat treatment at a lower temperature (1 hour at 55°C) and short heat treatments at a higher temperature (1 minute at 65°C). The obtained results show that the L. monocytogenes is able to increase its heat resistance in both situations, after successive cycles of heat treatment and growth.

[SPA] En las últimas décadas, el consumo de bebidas azucaradas se ha asociado con un mayor riesgo de enfermedades crónicas. Consecuentemente, las industrias alimentarias están desarrollando nuevas formulaciones con bajo contenido de azúcar y alto contenido en compuestos bioactivos. Así, este trabajo tiene como objetivo desarrollar nuevas bebidas funcionales, que constituyan una fuente dietética de compuestos fenólicos suplementadas con estevia, sucralosa o sacarosa, con el fin de estudiar la influencia del edulcorante durante su procesamiento y almacenamiento. El impacto de las tecnologías de procesamiento sobre el perfil fitoquímico y microbiológico se evaluó aplicando dos tratamientos térmicos a 60 y 80 °C durante 15 s. Se monitorizó el almacenamiento a 5 y 25 °C durante 60 días. Ambos tratamientos de pasteurización aseguraron la estabilidad microbiológica a lo largo de la vida útil. Además, el perfil fisicoquímico no mostró diferencias significativas entre las bebidas durante el período de almacenamiento de 60 días. [ENG] In recent decades, the consumption of sugary drinks has been associated with an increased risk of chronic diseases. Consequently, food industries are developing new formulations of beverages with low sugar and high bioactive compound contents. In this regard, this work aims to develop new functional beverages, which constitute a dietary source of phenolic compounds and supplemented with stevia, sucralose or sucrose, in order to study the influence of the sweetener during processing and storage. The impact of the processing technologies on phytochemical and the microbiological profile was evaluated by applying two heat treatments at 60 and 80 °C for 15 s. The storage at 5 and 25 °C was monitored for 60 days. Both pasteurization treatments ensured microbiological stability throughout shelf life. Moreover, the physicochemical profile did not display significant differences between beverages over a 60-day storage period.

In this study, we performed multi-objective model-based optimization of a potato-frying process balancing between acrylamide production and a quality parameter (yellowness). Solution analysis revealed that, for most of the Pareto solutions, acrylamide levels exceeded the EFSA recommendation. Almost equivalent optimal solutions were found for moderate processing conditions (low temperatures and/or processing times) and the propagation of the uncertainty of the acrylamide production model parameters led to Pareto fronts with notable differences from the one obtained using the nominal parameters, especially in the ranges of high values of acrylamide production and yellowness. These results can help to identify processing conditions to achieve the desired acrylamide/yellowness balance and design more robust processes allowing for the enhancement of flexibility when equivalent optimal solutions can be retrieved

In this article, the thermal inactivation of two Salmonella strains (Salmonella Enteritidis CECT4300 and Salmonella Senftenberg CECT4565) was studied under both isothermal and dynamic conditions. We observed large differences between these two strains, with S. Senftenberg being much more resistant than S. Enteritidis. Under isothermal conditions, S. Senftenberg had non-linear survivor curves, whereas the response of S. Enteritidis was log-linear. Therefore, weibullian inactivation models were used to describe the response of S. Senftenberg, with the Mafart model being the more suitable one. For S. Enteritidis, the Bigelow (log-linear) inactivation model was successful at describing the isothermal response. Under dynamic conditions, a combination of the Peleg and Mafart models (secondary model of Mafart; t* of Peleg) fitted to the isothermal data could predict the response of S. Senftenberg to the dynamic treatments tested (heating rates between 0.5 and 10 °C/min). This was not the case for S. Enteritidis, where the model predictions based on isothermal data underestimated the microbial concentrations. Therefore, a dynamic model that considers stress acclimation to one of the dynamic profiles was fitted, using the remaining profiles as validation. In light of this, besides its quantitative impact, variability between strains of bacterial species can also cause qualitative differences in microbial inactivation. This is demonstrated by S. Enteritidis being able to develop stress acclimation where S. Senftenbenberg could not. This has important implications for the development of microbial inactivation models to support process design, as every industrial treatment is dynamic. Consequently, it is crucial to consider different model hypotheses, and how they affect the model predictions both under isothermal and dynamic conditions.

In this study, we performed multi-objective model-based optimization of a potato-frying process balancing between acrylamide production and a quality parameter (yellowness). Solution analysis revealed that, for most of the Pareto solutions, acrylamide levels exceeded the EFSA recommendation. Almost equivalent optimal solutions were found for moderate processing conditions (low temperatures and/or processing times) and the propagation of the uncertainty of the acrylamide production model parameters led to Pareto fronts with notable differences from the one obtained using the nominal parameters, especially in the ranges of high values of acrylamide production and yellowness. These results can help to identify processing conditions to achieve the desired acrylamide/yellowness balance and design more robust processes allowing for the enhancement of flexibility when equivalent optimal solutions can be retrieved.

The “list of microorganisms with QPS status” first established in 2007, has been revised and updated annually until 2014 via QPS Opinions; since 2014 the updates are carried out and published every 3 years. If new information is retrieved from extended literature searches (ELS) that would change the QPS status of a TU or its qualifications, this is also published in the Panel Statement covering the previous 6-months period. The ELS protocol can be found at https://doi.org/10.5281/zenodo.3607190 and the Search strategies are available at: https://doi.org/10.5281/zenodo.3607193. The QPS Panel Statement also includes the evaluation of microbiological agents notified to EFSA within the 6-month period for an assessment for feed additives, food enzymes, food additives and flavourings, and novel foods or plant protection products for a possible QPS status. The new QPS status recommendations are incorporated into the 2019 updated “list of microorganisms with QPS status” is available in this upload. The list of “Microbiological agents as notified to EFSA” from 2007, in the context of technical dossiers to EFSA Units, for intentional use in feed and/or food or as sources of food and feed additives, enzymes and plant protection products (PPPs) for safety assessment can be found at https://doi.org/10.5281/zenodo.3607184.

[SPA] La tendencia del consumo de alimentos funcionales ha puesto de manifiesto el interés por las frutas de tipo baya debido a sus características de alta promoción de la salud propiedades antinflamatorias, antidiabéticas e hipoglucémicas. Chile produce varias bayas y una de ellas es el calafate (Berberis microphylla G. Forst) que posee un alto contenido de antocianinas. Varios estudios han demostrado el potencial de las antocianinas, sin embargo, su uso es limitado debido a la baja estabilidad en condiciones ambientales y/o la interacción con otros compuestos. En ese sentido, el uso de técnicas como la encapsulación es una opción. Este trabajo se centró en el desarrollo de una formulación para obtener microcápsulas de calafate mediante la técnica de secado por aspersión donde se obtuvo un 60 % de recuperación de compuestos bioactivos y tras la evaluación de la degradación de las antocianinas después del almacenamiento a temperatura ambiente se logró mantener estables en un 45 % las antocianinas mayoritarias (delphinidina-3-glucósido y petunidina-3-glucósido) de calafate durante 4 semanas., [ENG] The trend of functional foods consumption has remarked a huge interest for berry-type fruits due to its characteristics as high health-promoting and anti-inflammatory, anti-diabetic, and hypoglycaemic properties. Chile produces several berries and one of them is calafate (Berberis microphylla G. Forst). which has a high content of anthocyanins. Several studies have shown the potential of anthocyanins in preventive and curative treatments; however, their use is limited due to low stability under environmental conditions and / or interaction with other compounds. In that sense, the use of techniques such as encapsulation is an option. This work focuses on developing a formulation to get calafate microcapsules by using spray drying technique where 60 % recovery of bioactive compounds was obtained. The evaluation of anthocyanins degradation after storage at room temperature allow to keep the calafate anthocyanins (delphinidin-3-glucoside and petunidine-3-glucoside) stable at 45 % after 4 weeks at room temperature.

In food processes, optimizing processing parameters is crucial to ensure food safety, maximize food quality, and minimize the formation of potentially toxigenic compounds. This research focuses on the simultaneous impacts that severe heat treatments applied to food may have on the formation of harmful chemicals and on microbiological safety. The case studies analysed consider the appearance/synthesis of acrylamide after a sterilization heat treatment for two different foods: pureed potato and prune juice, using Geobacillus stearothermophilus as an indicator. It presents two contradictory situations: on the one hand, the application of a high-temperature treatment to a low acid food with G. stearothermophilus spores causes their inactivation, reaching food safety and stability from a microbiological point of view. On the other hand, high temperatures favour the appearance of acrylamide. In this way, the two objectives (microbiological safety and acrylamide production) are opposed. In this work, we analyse the effects of high-temperature thermal treatments (isothermal conditions between 120 and 135 _C) in food from two perspectives: microbiological safety/stability and acrylamide production. After analysing both objectives simultaneously, it is concluded that, contrary to what is expected, heat treatments at higher temperatures result in lower acrylamide production for the same level of microbial inactivation. This is due to the different dynamics and sensitivities of the processes at high temperatures. These results, as well as the presented methodology, can be a basis of analysis for decision makers to design heat treatments that ensure food safety while minimizing the amount of acrylamide (or other harmful substances) produced.

[SPA] Actualmente, las bebidas a base de frutas y hortalizas, como por ejemplo con cítricos y frutos rojos, con bajo contenido en azúcar, son una prometedora forma de consumo de nutrientes promotores de la salud. El desarrollo de bebidas organolépticamente atractivas y seguras, enriquecidas en compuestos bioactivos y biodisponibles, que aporten alternativas a los carbohidratos de rápida absorción, con la finalidad de reducir el consumo de azúcares en la población, conlleva la necesidad de una evaluación de la seguridad de los nuevos productos y una optimización de su procesado. Para ello se han de estudiar diferentes alternativas basadas en tratamientos térmicos y no térmicos. Además es necesario un análisis de decisión multi-criterio que optimice los resultados obtenidos, junto con las estimaciones de costes de las mismas, que será útil para optimizar su elaboración a escala industrial. [ENG] Nowadays, low-sugar plant-based beverages, such as those citrus and red fruit-based, are a promising way to consume health-promoting nutrients. The development of safe and organoleptic attractive beverages, enriched in bioactive and bioavailable compounds, is of high interest. This, together, with providing alternatives to fast-absorbing carbohydrates, with the purpose of reducing the consumption of sugars, implies the need for an evaluation of the safety of the new products and an optimization of their processing. In order to cover this, the study of different alternatives based on thermal and non-thermal treatments is of interest. Furthermore, a multi-criteria decision analysis is necessary to optimize the results obtained, together with the estimated costs of the different alternatives, which will be useful to improve its implementation on an industrial scale.

Alicyclobacillus acidoterrestris is a spoilage microorganism responsible for relevant product and economic losses in the beverage and juice industry. Spores of this microorganism can survive industrial heat treatments and cause spoilage during posterior storage. Therefore, an effective design of processing treatments requires an accurate understanding of the heat resistance of this microorganism. Considering that industrial treatments are dynamic; this understanding must include how the heat resistance of the microorganism is affected by the heating rate during the heating and cooling phases. The main objective of this study was to establish the effect of heating rates and complex thermal treatments on the inactivation kinetics of A. acidoterrestris. Isothermal experiments between 90 and 105 C were carried out in a Mastia thermoresistometer, as well as four different dynamic treatments. Although most of the inactivation takes place during the holding phase, our results indicate the relevance of the heating phase for the effectiveness of the treatment. The thermal resistance of A. acidoterrestris is affected by the heating rate during the heating phase. Specifically, higher heating rates resulted in an increased microbial inactivation with respect to the one predicted based on isothermal experiments. These results provide novel information regarding the heat response of this microorganism, which can be valuable for the design of effective heat treatments to improve product safety and stability. Moreover, it highlights the need to incorporate experimental data based on dynamic treatments in process design, as heating rates can have a very significant effect on the thermal resistance of microorganisms.

[SPA] La producción moderna de alimentos ha reducido el coste y ha aumentado la variedad de alimentos disponibles, pero esta centralización del suministro de alimentos presenta una oportunidad para que los patógenos y toxinas transmitidos por los alimentos infecten y envenenen a un gran número de consumidores. El modelado es una herramienta clave para garantizar la seguridad de los alimentos producidos a partir de materias primas para el consumidor final. La hipótesis inicial es que es posible mejorar la seguridad de los productos cárnicos listos para comer (LPC) mediante la evaluación/priorización de riesgos biológicos. La clasificación de riesgos de los riesgos para la salud de los alimentos y la seguridad alimentaria y nutricional se reconoce generalmente como el punto de partida para el establecimiento de prioridades basadas en el riesgo y la asignación de recursos, ya que permite a los encargados de formular políticas asignar sus recursos al problema de salud pública más importante. El resultado de esta tesis será una herramienta sólida de gestión de la inocuidad de los alimentos que puede ser implementada por todos los interesados, como las agencias de protección al consumidor (EFSA, ECDC) y la industria., [ENG] Modern food production has reduced the cost and increased the variety of food available, but this centralisation of the food supply presents an opportunity for foodborne pathogens and toxins to infect and poison large numbers of consumers. Modelling is a key tool to ensure the safety of food produced from raw material to the final consumer. The starting hypothesis is that it is possible to improve the safety of Ready To Eat (RTE) meat products by evaluation / prioritization of biological risks. Risk ranking of feed/food safety and nutritional related health risks is generally recognised as the starting point for risk-based priority setting and resource allocation, as it permits policymakers to allocate their resources on the most significant public health problem. The outcome of the thesis will be a robust tool for food safety management that can be implemented by all stakeholders, such as agencies related to consumer protection (EFSA, ECDC) and industry.

[SPA] Esta tesis doctoral se presenta bajo la modalidad de compendio de publicaciones. Calafate (Berberis microphylla G. Forst) es un arbusto silvestre que se distribuye en la Patagonia chilena y argentina. Sus frutos son de coloración, azul/púrpura y un sabor particular, características otorgadas por los compuestos fenólicos que la planta produce para hacer frente a las condiciones en las que se desarrolla. Al igual que otros frutos rojos, también conocidos como “berries” (por su término en inglés), gracias a su composición rica en una amplia gama de compuestos bioactivos, puede brindar beneficios para la salud, teniendo, por consiguiente, un gran potencial para el desarrollo de productos alimenticios y fuente de nuevas opciones dietéticas para el tratamiento de enfermedades. El presente trabajo de investigación describe la respuesta de las bayas de calafate frente al cambio climático, a través de la determinación de los perfiles de antocianos, a partir de frutos de calafate colectados en la región de Aysén, sur de Chile, así como la formulación, encapsulación y evaluación de dichos compuestos, su estabilidad después del almacenamiento y el estudio del potencial relacionado con su actividad enzimática (AChE) y su potencial para hacer frente a enfermedades neurodegenerativas. Finalmente, como aplicación práctica, se ha diseñado una bebida experimental a nivel de laboratorio. La capacidad de esta baya para adaptarse a los cambios por factores ambientales y la correlación de estos factores con los parámetros físico-químicos es clave para dilucidar la reacción de los frutos de calafate al cambio climático. Así, el capítulo III aporta información útil para apoyar a los programas de manejo agronómico y mejoramiento genético. El análisis de las bayas de calafate cosechadas en un origen nativo nos permitió confirmar su plasticidad para adaptarse a condiciones particulares de radiación solar y temperatura en la zona sur de Chile. Considerando que no había trabajos previos r

The qualified presumption of safety (QPS) approach was developed to provide a regularly updated generic pre-evaluation of the safety of biological agents, intended for addition to food or feed, to support the work of EFSA's Scientific Panels. It is based on an assessment of published data for each agent, with respect to its taxonomic identity, the body of knowledge, safety concerns and antimicrobial resistance. Safety concerns identified for a taxonomic unit (TU) are, where possible, confirmed at strain or product level, and reflected by ‘qualifications’. In the period covered by this statement, no new information was found that would change the status of previously recommended QPS TUs. Of the 36 microorganisms notified to EFSA between April and September 2020, 33 were excluded; seven filamentous fungi (including Aureobasidium pullulans based on recent taxonomic insights), one Clostridium butyricum, one Enterococcus faecium, three Escherichia coli, one Streptomyces spp. and 20 TUs that had been previously evaluated. Three TUs were evaluated; Methylorubrum extorquens and Mycobacterium aurum for the first time and Bacillus circulans was re-assessed because an update was requested in relation to a new mandate. M. extorquens and M. aurum are not recommended for QPS status due to the lack of a body of knowledge in relation to use in the food or feed chain and M. aurum, due to uncertainty concerning its pathogenicity potential. B. circulans was recommended for QPS status with the qualifications for ‘production purposes only’ and ‘absence of cytotoxic activity’.

[SPA] El incremento de enfermedades no transmisibles se atribuye principalmente a una mala alimentación. Un aumento en la concientización por parte de los consumidores ha aumentado la demanda de alimentos más saludables y convenientes. Este trabajo propone estudiar el efecto de tecnologías de conservación y procesado en parámetros de calidad nutricional de floretes de brócoli listos para consumir. El envasado en atmósfera modificada (MAP) es una tecnología ampliamente utilizada para la preservación de productos hortofrutícolas frescos y listos para consumir. Se propone estudiar el efecto de distintos parámetros de esta tecnología sobre el perfil y evolución de componentes de interés nutricional de floretes de brócoli listos para el consumo. Así como la degradación de estos componentes durante el almacenamiento del producto y realizar seguimiento de otros parámetros de calidad durante su vida útil. Otro aspecto importante son los métodos de preparación del brócoli previo a su consumo, los cuales inciden en la calidad nutricional. Por lo tanto, el estudio se complementará con una evaluación de los efectos de distintos métodos de cocinado en la conservación de los compuestos de interés nutricional. [ENG] The increase of noncommunicable diseases is mainly attributed to poor diet. Consumers are being more awareness about it, demanding healthier and more convenient foods. In this context, this work proposes to study the effect of preservation and processing technologies on parameters of nutritional quality of ready-to-eat broccoli florets. Modified atmosphere packaging (MAP) is a technology widely used to preserve fresh and ready-to-eat horticultural products. It is proposed to study the effect of different MAP parameters on the profile and evolution of nutritional compounds of ready-to-eat broccoli florets during storage. Additionally, other quality parameters and shelf life of the product will be evaluated. On the other hand, cooking processes previously applied to broc

[SPA] El objetivo de la presente tesis doctoral fue caracterizar los principales componentes químicos no volátiles, y el efecto de la zona geográfica de producción, sobre el contenido de estos fitoquímicos, en cacao Nacional ecuatoriano, como herramienta objetiva de calidad. De este modo, considerando que el cacao es uno de los principales productos de exportación del Ecuador, el presente trabajo podría servir para establecer nuevos parámetros para evaluar la calidad, certificar el origen y agregar valor al cacao ecuatoriano. Para lograr este objetivo, en primer lugar, se estableció un plan de muestreo, seleccionando las tres provincias de mayor producción de cacao Nacional en la región Litoral (Costa del Pacífico) y en la región Amazónica del Ecuador. En cada provincia se seleccionaron 3 cantones y en cada cantón 5 fincas de productores, tomándose un total de 85 muestras por duplicado. Los análisis se realizaron utilizando los métodos estandarizados en el laboratorio de Servicio de Análisis e Investigación en Alimentos (LSAIA) del Instituto Nacional de Investigaciones Agropecuarias (INIAP) en Ecuador. Una vez obtenidas las muestras, se procedió a determinar el contenido de metilxantinas (teobromina y cafeína) y el ratio de las mismas. Esta caracterización permitió establecer que el cacao Nacional ecuatoriano presenta mayores contenidos de teobromina, menores contenidos de cafeína y una relación teobromina/cafeína que varía en el rango de 5.2 a 7.6. Dicha relación permitió clasificar a esta variedad de cacao dentro del grupo de cacao tipo Trinitario. Todo ello demostró que los materiales ecuatorianos son “Finos”, puesto que comercialmente, a nivel mundial, se reconoce a los cacaos de tipo Trinitario y Criollo, como materiales para elaboración de chocolates “Finos”. El contenido en estas metilxantinas fue mayor en las muestras recogidas en la región amazónica. Posteriormente, se procedió a la determinación del contenido total en compuestos fenólicos y el contenido de, [ENG] The objective of this doctoral thesis was to characterize the main non-volatile chemical components and the effect of the geographical area of production on the content of these phytochemicals in Ecuadorian Nacional cocoa, as an objective quality tool. In this way, considering that cocoa is one of the main export products from Ecuador, the present work could serve to establish new parameters to evaluate the quality, certify the origin and add value to the Ecuadorian cocoa. To achieve this objective, in the first place, a sampling plan was established, selecting the three provinces with the highest production of National cocoa in the Litoral region (Pacific Coast) and in the Amazon region of Ecuador. In each province, three cantons were selected and in each canton five producer farms, taking a total of 85 samples in duplicate. The analysis was carried out using standardized methods in the Food Analysis and Research Service Laboratory (LSAIA) of the National Institute of Agricultural Research (INIAP) in Ecuador. Once the samples were obtained, the content of methylxanthines (theobromine and caffeine) and their ratio were determined. This characterization allowed to establish that the Ecuadorian Nacional cocoa has higher theobromine contents, lower caffeine contents and a theobromine/caffeine ratio that varies in the range of 5.2 to 7.6. This relationship allowed classifying this variety of cocoa within the group of Trinitario type cocoa, proving that the Ecuadorian materials are fine. Trinitario and Criollo type cocoas are recognized commercially worldwide as materials for making “Fine” chocolates. The content of these methylxanthines was higher in the samples collected in the Amazon region. Subsequently, the total content of phenolic compounds and the content of the main flavan-3-ols present in Ecuadorian Nacional cocoa were determined. The results showed that this variety of cocoa present contents of total phenolic compounds in the range of 33.55 ± 5.74 - 71.6

[SPA] Listeria monocytogenes es actualmente una de las principales preocupaciones de la industria alimentaria. Aunque el número de casos reportados en la Unión Europea es relativamente, tiene una gran gravedad, con unas tasas de hospitalización y mortandad del 97% y del 16,7%, respectivamente. Debido a la ubicuidad de este microorganismo y su capacidad de crecer en numerosas matrices alimentarias, las empresas agroalimentarias deben aplicar tratamientos que inactiven las células de L. monocytogenes. En este trabajo, se estudió la cinética de inactivación de L. monocytogenes aislada de productos marinos sometida a un tratamiento combinado de PEAV con un aceite esencial de orégano. Los resultados demuestran esta sinergia, ya que se consiguió una mayor inactivación microbiana con un campo de 20 kV/cm, 1 Hz de frecuencia, 150 pulsos y una concentración de orégano de 1/2 MIC, superior a la obtenida en las muestras control. Llegando a la conclusión de que los PEAV impulsan el efecto del orégano sobre la membrana de la bacteria. [ENG] Nowadays Listeria monocytogenes is one of the main concerns of the food industry. The number of cases reported in the European Union is relatively low it is very serious, with rates of hospitalization and mortality of 97% and 16.7%, respectively. Due to the ubiquity of this organism and its capacity to grow in many food matrices, agri-food companies must apply treatments that inactivate the cells of L. monocytogenes. In this work, it was studied the kinetics of inactivation of L. monocytogenes isolated from marine products subjected to a combined treatment of PEF with an essential oil of oregano. The results show this synergy, since it got a greater inactivation microbial with a field of 20 KV/cm, 1 Hz frequency, 150 pulses and an oregano concentration of 1/2 MIC, higher than that obtained in control samples. Concluding that the PEF promote the effect of oregano on the bacterial cell membrane.

This is the list of “Microbiological agents as notified to EFSA” from 2007, in the context of technical dossiers to EFSA Units, for intentional use in feed and/or food or as sources of food and feed additives, enzymes and plant protection products (PPPs) for safety assessment., This is the list of “Microbiological agents as notified to EFSA” from 2007, in the context of technical dossiers to EFSA Units, for intentional use in feed and/or food or as sources of food and feed additives, enzymes and plant protection products (PPPs) for safety assessment. This is supplementing the QPS statement part 11, part 12, part 13, part 14, part 15 and the 2019 Scientific Opinion of the BIOHAZ Panel of EFSA - see related identifiers. EFSA topic on QPS: https://www.efsa.europa.eu/en/topics/topic/qualified-presumption-safety-qps

The qualified presumption of safety (QPS) was developed to provide a generic safety evaluation for biological agents to support EFSA's Scientific Panels. It is based on an assessment of the taxonomic identity, the body of knowledge, safety concerns and antimicrobial resistance. Safety concerns identified for a taxonomic unit (TU) are where possible to be confirmed at strain or product level, reflected by ‘qualifications’. No new information was found that would change the previously recommended QPS TUs of the 39 microorganisms notified to EFSA between October 2019 and March 2020, 33 were excluded, including five filamentous fungi, five Escherichia coli, two Enterococcus faecium, two Streptomyces spp. and 19 TUs already evaluated. Six TUs were evaluated. Akkermansia muciniphila was not recommended for QPS status due to safety concerns. Clostridium butyricum was not recommended because some strains contain pathogenicity factors. This TU was excluded for further QPS evaluation. Galdieria sulphuraria and Pseudomonas chlororaphis were also rejected due to a lack of body of knowledge. The QPS status of Corynebacterium ammoniagenes (with the qualification ‘for production purposes only’) and of Komagataella pastoris (with the qualification ‘for enzyme production’) was confirmed. In relation to the taxonomic revision of the Lactobacillus genus, previously designated Lactobacillus species will be reassigned to the new species and both the old and new names will be retained in the QPS list.

[SPA] Debido a la evolución de la industria agroalimentaria y a los grandes avances de ésta, la seguridad alimentaria se considera como una de las principales prioridades. La necesidad de garantizar seguridad y preservar los atributos de calidad (nutricionales y sensoriales) han derivado en la necesidad de contar con herramientas cada vez más sofisticadas para producir alimentos de manera eficiente y en elevadas cantidades. Ello supone un reto para garantizar la estabilidad microbiológica manteniendo estándares muy elevados de calidad. El objetivo de este trabajo ha sido a través del uso de la Reacción en Cadena de la Polimerasa descartar la presencia de microorganismos patógenos como es el caso de Bacillus Cereus. [ENG] Due to the evolution of the agri-food industry and its great advances, food safety is considered one of its main priorities. The need to ensure safety and preserve quality attributes (nutritional and sensory) have led to the need for increasingly sophisticated tools to produce food efficiently and in high quantities. This is a challenge to ensure microbiological stability by maintaining very standards of quality. The objective of this work has been through the use of the Polymerase Chain Reaction to rule out the presence of pathogenic microorganisms such as Bacillus Cereus.

The mathematical models used in predictive microbiology contain parameters that must be estimated based on experimental data. Due to experimental uncertainty and variability, they cannot be known exactly and must be reported with a measure of uncertainty (usually a standard deviation). In order to increase precision (i.e. reduce the standard deviation), it is usual to add extra sampling points. However, recent studies have shown that precision can also be increased without adding extra sampling points by using Optimal Experiment Design, which applies optimization and information theory to identify the most informative experiment under a set of constraints. Nevertheless, to date, there has been scarce contributions to know a priori whether an experimental design is likely to provide the desired precisión in the parameter estimates. In this article, two complementary methodologies to predict the parameter precision for a given experimental design are proposed. Both approaches are based on in silico simulations, so they can be performed before any experimental work. The first one applies Monte Carlo simulations to estimate the standard deviation of the model parameters, whereas the second one applies the properties of the Fisher Information Matrix to estimate the volume of the confidence ellipsoids. The application of these methods to a case study of dynamic microbial inactivation, showing how they can be used to compare experimental designs and assess their precision, is illustrated. The results show that, as expected, the optimal experimental design is more accurate than the uniform design with the same number of data points. Furthermore, it is demonstrated that, for some heating profiles, the uniform design does not ensure that a higher number of sampling points increases precision. Therefore, optimal experimental designs are highly recommended in predictive microbiology.