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The purpose of the present study was to examine the inactivation of Salmonella enterica (50 μL; 109 CFU g−1), Listeria monocytogenes (50 μL; 109 CFU g−1), and murine norovirus (MNV-1; 50 μL; 107 50% tissue culture infectious dose (TCID50) mL−1) on whole and fresh-cut strawberries after 2 min disinfection treatments (water (H2O), chlorine 200 mg L−1 (NaClO), water-assisted ultraviolet-C (UV-C) (WUV), and the combination WUV and 40 mg L−1 of PA (WUV + PA)) in a water tank (15 L) equipped with 4 UV-C lamps (17.2 W each), and after 7 days of cold storage (4 and 10 °C). For MNV-1, dry UV-C treatment (DUV) was also tested. For all UV-C treatments, an irradiation dose of 1.3 kJ m−2 was used. RESULTS: When strawberries were washed with WUV, L. monocytogenes and S. enterica were reduced by 2.8 and 2.2 log CFU g−1, respectively. The addition of 40 mg L−1 of PA to WUV (WUV + PA) increased the reduction range of L. monocytogenes and S. enterica by 1.9 and 0.8 log, respectively. Regarding the wash water, no pathogens were recovered after the WUV + PA treatment (detection limit 50 CFU mL−1). Depending on storage conditions (7 days at 4 or 10 °C), reductions observed were 0.5 to 2.0 log for S. enterica and 0.5 to 3.0 log for L. monocytogenes. The reductions in MNV-1 titer after disinfection treatments ranged from 1.3 to 1.7 log. No significant differences between storage conditions were observed for MNV-1: titers did not decline or were reduced up to 0.3 log after 7 days of cold storage. CONCLUSION: The three-way action for disinfecting strawberries by UV-C irradiation and PA, plus the physical removal of the microorganisms by agitated water, are effective against foodborne pathogens on strawberries and water wash. During storage, WUV had a larger impact on the inactivation kinetics of S. enterica. Storage had little impact on MNV-1 inactivation. The authors are grateful to the Spanish government (Ministerio deEconomía y Competitividad, research project AGL2016-78086-R)and the Centres de Recerca de Catalunya (CERCA) Programmeof‘Generalitat de Catalunya’for itsfinancial support. J. Ortiz-Solàthanks the University of Lleida for its PhD grant (BOU186-243/2017 UdL) and M. Anguera thanks them for their techni-cal support. I. Nicolau-Lapeña is in receipt of a predoctoral grantawarded by the‘Ministerio de Economía, Industria y Competitivi-dad’(grant number BES-2017-079779). The authors gratefullyacknowledged the assistance of Gloria Sánchez and Susana Guixfor teaching them the methodologies related to MNV-1 andRAW 264.7 assays.

Foodborne pathogens represent a major concern for the food industry, which needs to ensure that products are safe for consumers. Predictive microbiology is a multidisciplinary area of food mi crobiology, which is devoted to studying and predicting, by means of mathematical models, the cffects of extrinsic factors (temperature, salt, preservatives, etc.) on microbial behaviour in foods. The present chapter is an overview of the successive steps to follow for the successful development and implementation of a predictive model, as well as the most common types of secondary mod­els used in food microbiology. The chapter continues with a general review of the most powerful predictive microbiological tools (tertiary models) that are currently available on the worldwide web for foodborne patho­gens, and concludes by commenting on the direct implications and applications of predictive microbiology in food safety and microbial risk assessments., Funding was provided by the European Project (VII Framework Program: KBBE 22738 BASELINE), the Spanish Government (projects AGL2009-07436/ALI, AGL2010-l549 and AGL2010-15529 partially financed by European regional development funds, ERDF) and Junta de Andalucía (Excellence Project CTS-08-03620 and through financial support to group AGR-125 and AGR-170). J. Bautista-Gallego and F.N. Arroyo-López thank the ltalian and Spanish governments for their Assegno di Ricerca and Ramón y Cajal postdoctoral research contracts, respectively.

The establishment of validated methodologies for the determination of food shelf-life is currently demanded by both food industries and Health Authorities at national and international scale. It is well known that most foods are perishable, since they are subjected to modifications in their structure, composition and properties during storage before consumption. These changes are of physico-chemical origin attributed to food composition together with the action of intrinsic and extrinsic environmental factors, and also microbiological, where spoilage flora play an important role. These modifications are “translated into“ sensorial deterioration at a specific time point. In this respect, food-borne bacteria, despite representing a threat for consumers´ health, do not affect sensorial changes

La presente Tesis Doctoral estudia la viabilidad de nuevas elaboraciones de aceitunas de mesa con variedades autóctonas del Valle del Guadalhorce, como son el caso de la Aloreña de Málaga y la Campiñesa. Para ambas variedades se ha hecho un seguimiento fisicoquímico, microbiológico, y sensorial del proceso de elaboración como verdes al estilo español, principal tipo de elaboración a nivel mundial de aceitunas de mesa, además de la realización de estudios de genotipado al final de la etapa fermentativa. Esta Tesis Doctoral también incluye el estudio de la influencia de la metodología de envasado sobre la estabilidad fisicoquímica, microbiológica y organoléptica de aceitunas Aloreñas curadas ecológicas. En la actualidad las aceitunas Aloreñas de Málaga se procesan como verdes naturales, debido a su bajo contenido en oleuropeína, compuesto responsable del amargor de las aceitunas, no necesitando tratamiento alcalino. Existe un porcentaje de aceitunas de esta variedad que por su pequeño tamaño no cumplen los estándares de calidad que se establecen para ser procesadas con el sello de la DOP, se destinan a la producción de aceite, mismo destino del 100 % de la producción de aceitunas de la variedad Campiñesa, aceitunas con una producción muy localizada en este entorno. La gran demanda existente de aceitunas de mesa ha llevado a pensar que ambas variedades podrían ser elaboradas como aceitunas de mesa al estilo español innovando en el tipo de procesado que se emplea en la actualidad, aumentando así la oferta de productos en el mercado. Para evaluar la viabilidad de las dos variedades elaboradas al estilo español, durante la campaña 2018/2019 se estudiaron los parámetros influyentes en la calidad de las aceitunas de mesa, prestando especial atención a la etapa de cocido, ensayándose diferentes concentraciones de hidróxido de sodio. Asimismo, tras el cocido y el lavado, se hizo un seguimiento y estudio de los diferentes parámetros microbiológicos y fisicoquímicos durante la fermentación que fue dirigida por la adición del cultivo iniciador OleicaStarter® (compuesto por dos cepas de Lactiplantibacillus pentosus 13B4 y 119). Tras la fermentación se estudió el efecto de la conservación con altas concentraciones de cloruro de sodio, y la influencia del tipo de envasado, frasco de vidrio con salmuera (durante 8 meses) y bolsa de plástico con atmósfera modificada de nitrógeno (durante 6 meses), para conocer la posible viabilidad comercial de estas aceitunas. Durante la segunda campaña se desarrollaron modelos predictivos para la variedad Aloreña de Málaga calibre perdigón, que cuantificaron la evolución del comportamiento microbiano y los parámetros fisicoquímicos durante la fermentación para dos tratamientos de cocido, con el objetivo de conocer la influencia de los factores y formulaciones empleadas sobre la cinética en las salmueras de fermentación. Con respecto a las aceitunas Campiñesas, el ensayo de la segunda campaña se enfocó, en el uso de diferentes cultivos iniciadores de bacterias ácido lácticas (OleicaStarter® y Lp309) con el objetivo de favorecer el desarrollo de una fermentación láctica y conseguir una mayor estandarización del proceso. El estudio con aceitunas Aloreñas curadas ecológicas con sello DOP ha tenido como objetivo el desarrollo de nuevas técnicas de envasado, en las que se usaron diferentes líquidos de gobierno (agua de mar, agua de manantial o agua de red), diferentes aliños (oleorresinas o especias naturales), y solo una parte de los envasados fueron sometidos a tratamiento térmico de pasterización. A lo largo de la vida de mercado se evaluaron los parámetros fisicoquímicos y microbiológicos junto con estudios organolépticos de los nuevos productos elaborados. Se concluye, que las aceitunas de la variedad Aloreña de Málaga con calibre perdigón, pueden elaborarse como aceitunas verdes al estilo español, resultando un producto seguro que cumple con las exigencias de calidad y seguridad alimentaria. Además, la etapa de fermentación pudo ser descrita de forma precisa a través del desarrollo de modelos predictivos. Por el contrario, las aceitunas Campiñesas presentaron mayores dificultades en su elaboración, siendo necesario la utilización de cultivos iniciadores de bacterias ácido lácticas más resistentes a las condiciones de las salmueras que ayudaron al desarrollo correcto de la fermentación y a la rápida estabilización del producto. Asimismo, si por motivos logísticos estas variedades debieran ser conservadas en vez de envasadas, no existiría una merma sustancial en términos de calidad, pudiendo ser envasadas bajo demanda. El estudio de envasados de aceitunas curadas Aloreñas ecológicas, la no pasteurización de los distintos envasados produjo refermentaciones en algunas de las presentaciones estudiadas. Por tanto, se concluyó que el empleo de un tratamiento térmico mantiene el producto con mayor estabilidad durante el periodo de vida de mercado estudiado, obteniéndose mayor aceptación de consumo. This Doctoral Thesis studies the feasibility of new elaborations of table olives with autochthonous varieties of the Guadalhorce Valley, Aloreña de Málaga and Campiñesa. For both varieties, a physicochemical, microbiological, and sensory monitoring of the Spanish-style elaboration process has been carried out, being the main table olive processing worldwide. Besides, genotyping studies have been performed at the end of the fermentation stage. This Doctoral Thesis also includes the study of the influence of the packaging methods on the physicochemical, microbiological, and sensorial stability of organic cured Aloreña table olives. Table olives corresponding to the Aloreña de Málaga variety are currently processed as natural green olives, due to their low content of oleuropein, a compound responsible for the bitterness of the olives, not requiring alkaline treatment. There is a percentage of olives of this variety that, due to their small size, do not meet the quality standards established to be processed with the PDO certification. Thus, they are destined for production of olive oil, as 100% of the production of olives from the Campiñesa variety, having a very localized production in this environment. The increasing demand for table olives has led to think that both varieties could be elaborated as Spanish-style table olives. This would result in a processing type innovation, thus increasing the supply of products on the market. To assess the viability of the two varieties made in the Spanish-style, during the 2018/2019 season, the parameters influencing the quality of table olives were studied, deserving special attention to the lying treatment by using different concentrations of sodium hydroxide. Likewise, after lying and washing, the different microbiological and physicochemical parameters were monitored and studied during fermentation, which was directed by the addition of the OleicaStarter® starter culture (composed of two strains of Lactiplantibacillus pentosus 13B4 and 119). After fermentation, the effect of olives preservation was studied at different high concentrations of sodium chloride, as well as the influence of the type of packaging, i.e., glass jars with brine (for 8 months) and plastic bags with modified atmosphere of nitrogen (for 6 months), to know the commercial viability of these olives. During the second campaign, predictive models were developed for the small-sized Aloreña de Málaga variety. These models quantified the evolution of the microbial behavior and the physicochemical parameters during fermentation for two lying treatments, with the aim of understanding the influence of the factors and formulations used on the kinetics of fermentation brines. Regarding the Campiñesas olives, the trial of the second campaign focused on the use of different lactic acid bacteria starter cultures (OleicaStarter® and Lp309) with the aim of enhancing the development of lactic acid fermentation and process standardization. Regarding the study with organic cured Aloreñas olives with the PDO certification was the development of new packaging techniques using different brines (sea water, spring water or tap water), seasonings (oleoresins or natural spices), and the application or not of a pasteurization treatment. Throughout the shelf-life, the physicochemical and microbiological parameters were evaluated along with sensorial studies of the finished products. It is concluded that the small-sized Aloreña de Málaga can be produced as green Spanish-style table olives, resulting in a safe product meeting the quality and food safety standards. In addition, fermentation can be accurately described using different predictive models. On the contrary, the Campiñesas olives presented more difficulties for elaboration, being necessary the use of alternative lactic acid bacteria starter cultures more resistant to the conditions of the brines achieving a correct fermentation and a rapid stabilization of the product. Likewise, if for logistical reasons these varieties had to be preserved instead of packaged, there would be no substantial loss in terms of quality, and they could be packaged on demand. The study of packaging of organic Aloreña cured olives, the unpasteurized packages led to product refermentations in some of the studied presentations. Moreover, it was concluded that the use of a heat treatment maintains the product with greater stability during the studied shelf- life, achieving higher consumers’ acceptance.