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Brick manufacturing is a traditional activity carried out by the practical knowledge transmitted person to person, why there is no documentation on the raw material and manufacturing process control. The objective of this study was to determine the physicochemical characteristics of the raw material used in the fabrication of the Bricks, as a first instance to be able to make future changes for the quality assurance of the process that allow increasing the resistance to compression of the bricks. A mechanical test about the compressive strength of bricks before and after heat treatment was made. In the analysis of elemental composition, the presence of the following elements was found: C, O, Na, Mg, Al, Si, K, Ca, Ti, Fe. These elements allowed to obtain a compressive strength of the bricks of 10 to 13kg/cm2 without heat treatment and 20 to 40 kg/cm2 with heat treatment. Morphologically particles of 5 to 300 micrometres were observed in the raw material, and in the Bricks of 15 to 250 micrometres. It is concluded that the great variation of particle size of the raw material leads to a low compressive strength. Other studies with more control in the homogenization of particle size are suggested to obtain greater compression strength. Besides the temperature control in the kiln used to heat treatment is needed. The International Standard ITINTEC 331,017, and the Standard NMX-C-404-1997, establishes 60N / cm2, and 24kg / cm2 as minimum respectively. This study serves as a basis for further studies to help control and ensure the quality of the bricks.

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Due to its bioactive properties, oregano essential oil (OEO) is being included in new food packaging materials. However, due to essential oils (EOs) high volatility, ageing and conditions of films preparation may cause losses and diminish the activity, Analytical pyrolysis (Py-GC/MS) is a tool providing fingerprinting and precise information about composition, quality and additives in active packages made with biogenic polymers, In a previous work, we used Py-GC/MS combined with d13C analysis to ensure that no appreciable EO losses occurred when our polylactic acid (PLA) polybutylene succinate (PBS) (95:5) films containing OEO were developed. We confirmed that the OEO remained in adequate quantities and bioactive after the extrusion process. In a subsequent study, the effect of this bio-package in lettuce shelf life and its effect in the chemical composition of the food that contains was evaluated, and specifically in the conservation of specific compounds with dietetic value. In this work we describe a detailed Py-GC/MS study performed to detect changes in the relative contents of polyunsaturated fatty acids (PUFAs) and phytosterols in iceberg lettuce after 1, 4 and 8 days packaged in PLAlPBS (95:5) films containing different quantities of OEO (O , 2, 5 and 10%). Our results indicate that films containing any quantity of OEO, used in packages with a proportion of 5.5 9 of film/kg lettuce, allow maintaining the profile of lettuce PUFAs and phytosterols during the shelf life of the packed food., Projects AGL2012-38357-C02-01 and CGL2012-38655-C04-01, cofinanced by FEDER. María Llana-Ruiz-Cabello acknowledges Junta de Andalucia predoctoral grant associated to AGR7252 project.

Póster presentado en el la XVI Reunión Científica de la Sociedad Española de Cromatografía y Técnicas Afines (SECyTA2016) P‐IA‐2, Isotope ratio mass spectrometry (IRMS) has become a key tool for scientists in many disciplines and the practical applications of the technique are continuously growing. While no or little sample preparation is required for bulk isotopic analyses, for compound‐specific isotope analysis (CSIA) usually intermediate preparative procedures are required prior to chromatographic analysis to isolate analytes from geological, biological or synthetic materials. In addition, non‐volatile compounds must be made amenable to GC by derivatization or treated before chromatographic separation adding complication. Analytical pyrolysis is a long established technique that can help overcome preparative manipulation of samples. The sample is heated up in an inert atmosphere (usually He) to decompose into smaller units (pyrolysate) which are transferred for chromatographic separation to a GC connected to an appropriate detector. In this communication we describe the results obtained by hyphenating analytical pyrolysis (Py‐GC) with carbon IRMS for the analysis of a polylactic acid (PLA) based film extruded with variable quantities of natural plant extracts or essential oils for use in active food packaging. Chemical structural information of pyrolysates was first determined by conventional analytical pyrolysis (Py‐GC/MS). Bulk δ13C measures were performed for each material by EAIRMS. The direct study of δ13C carbon isotopic signature in specific compounds was done by coupling a pyrolysis unit to a gas chromatograph connected (via Thermo Scientific GC‐Isolink System) to a continuous flow IRMS unit (Py‐GC‐(FID)‐EA‐IRMS). Using this Py‐CSIA device it was possible to trace natural additives with light δ13C signatures derived from C3 photosystem vegetation, from the heavier bio‐plastic backbone usually derived from corn (C4 vegetation) starch. Finally the results are discussed in terms of the potential of this new chromatographic application for food traceability and security., N.T. Jiménez‐Morillo to ‘Ministerio de Economía y Competitividad’ grant BES‐2013‐062573. M. Llana‐Ruiz‐Cabello to ‘Junta de Andalucía’ grant associated to AGR‐7252. Projects CSIC10‐1E‐448, CGL2012‐38655‐C04‐01 and AGL2012‐38357‐C02‐01 co‐financed by FEDER Funds, and Junta de Andalucía (AGR‐7252).

6 páginas.-- 4 figuras.-- 38 referencias, BACKGROUND Environmental, economic and safety challenges motivate shift towards safer materials for food packaging. New bioactive packaging techniques, i.e. addition of essential plant oils (EOs), are gaining attention by creating barriers to protect products from spoilage. Analytical pyrolysis gas chromatography–mass spectrometry (Py-GC-MS) was used to fingerprint a bioactive polylactic acid (PLA) with polybutylene succinate (PBS) (950 g kg−1:50 g kg−1) film extruded with variable quantities (0, 20, 50 and 100 g kg−1) of Origanum vulgare EO. RESULTS Main PLA:PBS pyrolysis products were lactide enantiomers and monomer units from the major PLA fraction and succinic acid anhydride from the PBS fraction. Oregano EO pyrolysis released cymene, terpinene and thymol/carvacrol peaks as diagnostic peaks for EO. In fact, linear correlation coefficients better than 0.950R2 value (P < 0.001) were found between the chromatographic area of the diagnostic peaks and the amount of oregano EO in the bioplastic. CONCLUSION The pyrolytic behaviour of a bio-based active package polymer including EO is studied in detail. Identified diagnostic compounds provide a tool to monitor the quantity of EO incorporated into the PLA:PBS polymeric matrix. Analytical pyrolysis is proposed as a rapid technique for the identification and quantification of additives within bio-based plastic matrices. © 2015 Society of Chemical Industry, This work was partly funded by the Spanish ‘Ministerio de Economía y Competitividad’ through projects CGL2012-38655-C04-01 and AGL2012-38357-C02-01 co-financed by FEDER Funds, and Junta de Andalucía (AGR-7252). N.T. Jiménez-Morillo is funded by a FPI research grant (BES-2013-062573).

El aceite esencial de especies del género Allium sp. contiene sustancias biológicamente activas, incluyendo algunas sustancias volátiles organosulfuradas, responsables de sus propiedades antimicrobianas y antioxidantes. El aislamiento químico del propil propano tiosulfonato (PTSO) da lugar a un preparado activo que podría usarse en la industria alimentaria. Dicho compuesto se incorporaría a una matriz comercial inerte, con el fin de ser utilizado como envase activo. Con el objetivo de poder evaluar la genotoxicidad in vivo de dicho organosulfurado, y teniendo en cuenta el protocolo de la OCDE 489 y 474, es necesario en primer lugar determinar la presencia del compuesto en plasma y/o órganos seleccionados para su posterior evaluación. Por ello, el presente estudio se centra en la determinación de PTSO en plasma, estómago e hígado de ratas intoxicadas por sonda gástrica a 55 mg/kg. La cuantificación del PTSO en plasma fue determinada por UHPLC¿MS/MS Orbitrap. En el estómago e hígado, la identificación de PTSO y/o sus productos de degradación se llevaron a cabo por pirólisis analítica. Además, los productos de degradación fueron separados por cromatografía y combinados y detectados con un espectrómetro de masas (Py-GC¿MS). El PTSO no fue detectado a ninguna de las concentraciones ensayadas en plasma; sin embargo, se detectaron seis componentes organosulfurados derivados de PTSO en estómago. Entre ellos, se encontró el disulfuro de dimetilo y propildisulfito de metilo, los cuales probablemente se originaron directamente a partir de PTSO, tras sufrir reacciones de hidrólisis. Tanto en el hígado de ratas tratadas se encontró el compuesto 2-metil-2-(metiltioltio)-propano indicando la influencia de los procesos de distribución y metabolismo de PTSO en ratas. En este trabajo se demuestra por primera vez la utilidad de la pirolisis analítica como técnica innovadora que permite confirmar la absorción e identificación de PTSO así como sus metabolitos en tejidos dianas., Los autores agradecen al Ministerio de Innovación y Ciencia del Gobierno de España cofinanciados con fondos FEDER, a la Junta de Andalucía (AGR-7252); y al servicio de microscopía del Citius de la Universidad de Sevilla por el apoyo técnico prestado.

Póster presentado en el la XVI Reunión Científica de la Sociedad Española de Cromatografía y Técnicas Afines (SECyTA2016) P‐NP‐1, Eds: González-Pérez, José Antonio.-- Almendros Martín, Gonzalo.-- González-Vila, Francisco Javier.-- Rosa Arranz, José M. de la, Responding to consumer demands on minimal processing and preservative‐free products, the use of essential oils (EOs) to extend shelf life of foods is on the spot in the food industry [1]. Carvacrol, main compound of Oregano EO, is registered as a flavouring in Europe; however, its use for other applications, such as active food packaging, may require higher concentrations and there is an increasing concern regarding exposure. Because of this, the European Food Safety Authority (EFSA) requires additional genotoxic studies data of substances which could be incorporated into food packaging like carvacrol. Here a detailed analytical pyrolysis (Py‐GC/MS) study is conducted as a complement to in vivo genotoxicity studies. Analytical pyrolysis was the technique chosen to search for carvacrol directly in viscera and to confirm that the compound effectively reached target tissues from orally exposed (0, 81, 256 or 810 mg carvacrol/kg bw, calculated according to carvacrol Maximum Tolerated Dose (MTD)) young adult male Wistar rats strain RjHan:WI*. Doses were prepared in corn oil at a final volume of 1 mL and during the treatment period, clinical signs, body weight, and food and water consumption were recorded daily. Rat stomach and liver composite samples were selected for pyrolysis and preserved at ‐80ºC until lyophilisation (Testal Cryodos, Madrid). Direct pyrolysis was performed in a double‐shot pyrolyzer (Frontier Lab 2020i) attached to a GC/MS system (Agilent 6890N + 973MSD). Detailed chromatographic conditions can be found in [2]. In short, lyophilized tissue (stomach and liver) were thoroughly homogenized and samples introduced (0.5 mg) into a preheated micro‐furnace at 500 ºC for 1 min and evolved gases transferred to the GC/MS for analysis. Compounds assignment was via single‐ion monitoring and by comparison with published and stored (NIST and Wiley libraries) data. In a previous study, it was determined that pyrolysis of carvacrol does not to produce major effects on its chemical structure and therefore was considered an adequate technique to detect the presence of the monoterpene in animal tissues. The analytical pyrolysis of target tissues of control rats was negative to any sign of carvacrol even when searching for the specific mass fragments (m/z 135 and 150). However, carvacrol was clearly detected in the tissues of rats treated at all doses. Furthermore, when normalizing the chromatograms to a common peak, a clear dose response was obtained. A conspicuous difference was found in the dose‐response curves between stomach and liver; whereas a direct lineal correlation could be drawn from the former, the response for the latter was best fit to a quadratic equation model. In this regard, the differences observed in those curves may be related to carvacrol metabolism in rats and the possible occurrence of saturation mechanisms limiting an excess of carvacrol metabolization/presence in liver. als received humane care., [1] M. Llana‐Ruiz‐Cabello, S. Pichardo, A. Baños, C. Nuñez, J.M. Bermúdez, E. Guillamón, S. Aucejo, A.M. Cameán, Food Sci. Technol‐LEB 64 (2015) 1354‐1361 [2] M. Llana‐Ruíz‐Cabello, S. Pichardo, N.T. Jiménez‐Morillo, J.M. Bermúdez, S. Aucejo. F.J. González‐Vila, A.M. Cameán, J.A. González‐Pérez (2016). J. Sci. Food Agr. 96 (2016) 3207‐3212 (*) The Ethics Committee on Animal Experimentation of the University of Sevilla approved the in vivo experiments. Moreover, in compliance with the Directive 2010/63/EU for the protection of animals used for scientific purposes all anim

El aceite esencial de orégano (Origanum vulgare L. virens) (OEO) es uno de los extractos naturales más interesantes para la industria alimentaria por sus propiedades antioxidantes y antimicrobianas. El carvacrol, su compuesto mayoritario, es uno de los compuestos fenolicos que le confiere estas propiedades al aceite. Para evaluar la seguridad de estas sustancias, la Autoridad Europea de Seguridad Alimentaria (EFSA) exige una serie de ensayos tanto in vitro como in vivo que estudien la capacidad genotóxica de las mismas. Para poder evaluar in vivo la genotoxicidad de carvacrol mediante la combinación del test de micronúcleos (MN) y del ensayo cometa, es necesario confirmar la exposición de los tejidos a esta sustancia. En este sentido, en el presente trabajo se evaluó mediante técnicas de pirólisis analítica (Py-CG/MS) la presencia de carvacrol en estómago e hígado de ratas Wistar expuestas por vía oral a distintas dosis de carvacrol (81, 256, 810 mg/ kg). Los resultados muestran por primera vez la presencia del compuesto en todos los órganos analizados. Por ello, demostramos que la técnica de pirólisis analítica es útil para obtener información sobre la exposición de los tejidos biológicos al agente activo., Los autores agradecen al Ministerio de Ciencia e Innovación (AGL2012-38357-C02-01 cofinanciado con fondos FEDER y CGL2012-38655-C04-01) y a la Junta de Andalucía (AGR- 7252) la financiación de este proyecto. M Llana-Ruiz-Cabello agradece a la Junta de Andalucía por su beca predoctoral y NT Jiménez-Morillo por su beca FPI (BES-2013-062573).

Poster presentado en el XX Congreso Español de Toxicología y IV Iberoamericano: P-SA/32 (2014), Los envases activos, diseñados para mejorar la vida útil de los alimentos perecederos, están convirtiéndose en una alternativa interesante frente al envasado tradicional. En este sentido, el aumento de la preocupación de los consumidores por su salud y la del medio ambiente está desplazando el uso de aditivos y polímeros sintéticos. En el presente trabajo se evalúa mediante técnicas de pirólisis analítica (Py-CG/MS) la incorporación de Proallium®, un agente antimicrobiano natural procedente de especies del género Allium, en una matriz polimérica de ácido poliláctico (PLA) y polisuccinato de butileno (PBS) (95:5). La pirólisis del bioplástico permitió detectar enantiómeros de lactida y unidades monoméricas procedentes de la degradación del PLA y del PBS, mientras que el activo (Proallium®) produjo una serie de compuestos sulfurados. Se observaron correlaciones lineales, con coeficientes, AGL2012-38357-C02-01; CGL2012-38655-C04-01; AGR-7252; BES-2013-062573