In recent years, the use of agrochemicals has increased because they are essential for profitable agricultural production. Herbicides are heavily demanded compounds and among these, the most marketed are 2,4-D, atrazine and acetochlor. They have characteristics that can cause problems to humans and the environment. Therefore, it is necessary to design systems that can reduce these compounds to harmless molecules. This work aims at evaluating the possibility of incorporating these herbicides into degradable effluents in a biological treatment system, without reducing its efficiency. For this purpose, studies of organic matter degradability in the presence of these agrochemicals were performed. A synthetic effluent based on glucose and mineral salts was inoculated with microorganisms. Glucose consumption and biomass concentration were assessed. Subsequently, preliminary studies were performed to test the viability of degradation of the most harmful compound with an advanced oxidation process (AOP). The results showed that the incorporation of these herbicides into degradable effluents in a biological treatment system has a negative impact on microorganisms. Therefore, the application of an AOP, such as the Fenton or photo-Fenton processes, prior to a biological treatment was found to degrade these substances to simpler and less toxic molecules.

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RESUMENLa elaboración de embutidos crudo-curados tiene lugar en cuatro etapas básicas: picado, amasadoreposo, estufado y secado. La formación del color en estos productos responde a mecanismos físicos, químicos y bioquímicos relacionados con las características de la carne cruda, los aditivos y especias utilizadas y la tecnología aplicada. El picado resulta importante en la formación del color debido a que provoca la desorganización estructural del tejido, favorece la incorporación de aire a la masa exponién-dola al oxígeno del aire, determina la salida de componentes sarcoplasmáticos y de líquido tisular hacia la superficie de la pasta y facilita el contacto íntimo de los aditivos y especias con el pigmento natural (Mb) de la carne. El objetivo del trabajo fue evaluar la influencia del picado en el desarrollo del color en sistemas modelo de pastas cárnicas elaboradas con magro de cerdo y adicionadas de diferentes mezclas de aditivos y pimentón. Se utilizó para ello la espectrofotometría de reflectancia y el espacio de color CIELAB. El picado fino produjo valores superiores de L*, a*, b* y C* respecto de los picados con placa (10 y 20 mm), y menores valores del índice a*/b*. La disminución del pH de las pastas debido al ácido láctico provocó la desnaturalización y la variación de las diferentes formas de Mb presente en las pastas. Dicho efecto fue superior en pastas finas adicionadas con 1,0 % de ácido láctico. Esto originó una disminución de los componentes rojos (a*) y un aumento de los amarillos (b*) a expensas de los primeros. Por otra parte, la disminución de a*/b* mostró que el ácido láctico favoreció la formación de MetMb.

Wastewater from cider factories (losses during transfers, products discarded due to quality policies, and products returned from the market) exhibits a Chemical Oxygen Demand greater than 170,000 mg O 2 /l, mainly due to the ethanol content and carbohydrates that are added to obtain the finished product. These effluents can represent up to 10% of the volume of cider produced, and they must be treated to meet environmental regulations. In this work, a process was developed, based on alcoholic fermentation of the available carbohydrates present in ciders. The impact of inhibitors at different pH, size and reuse of inoculums and different nutrient supplementation on the ethanol yield were evaluated. The use of a 0.5 g/l yeast inoculum and corn steep water as the nutrient source allowed for depletion of the sugars in less than 48 h, which increased the content of ethanol to more than 70 g/l.