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This study evaluated the incidence and identify the Listeria monocytogenes potential contamination in a poultry slaughter plant and assessed the effectiveness of the sanitation process used by the company. A total of 920 breast and 774 thigh samples were analyzed, and L. monocytogenes was found in 8.64 and 44.19% of the samples, respectively. The thigh samples presented more contamination than the breast, throughout the study. The third work shift showed the highest thigh contamination (51%). The contamination percentage was lowest in summer and greater in winter. L. monocytogenes contamination in whole carcasses was absent in samples collected before the chilling process, while 5% of the samples were contaminated after this process. After the automated cutting process, the L. monocytogenes contamination percentage increased linearly, reaching 25 and 70% after 5 h for breast and thighs, respectively. The percentage of contamination on the equipment and utensils used on thigh samples was high during the processing (86.67%) and after the cleaning operation (66.87%). After pre-operational sanitation of equipment and utensils a lower incidence of L. monocytogenes in the production line was observed.

The objective of this work was to evaluate and compare the chemical profile of essential oils of marjoram (Origanum majorana) and oregano (Origanum vulgare) obtained by hydrodistillation and supercritical CO2. The yield of marjoram and oregano essential oils obtained by supercritical CO2 was higher than those from hydrodistillation. Both essential oils presented similar chemical profiles. The major compound was terpinen-4-ol in essential oil obtained by hydrodistillation and cis-sabinene hydrate in the essential oil obtained by supercritical CO2, to both species. The hydrodistillation method showed higher quantitative differences between the extraction fractions in relation to the supercritical extraction. The extracts obtained by supercritical CO2 presented higher concentrations of oxygenated monoterpenes, without significant differences between fraction 1 and 2. A comparison between the extraction methods showed a higher extraction capacity of monoterpene hydrocarbons by hydrodistillation and ox...

Las cañas de bambú son un material de construcción único para diversos tipos de estructuras y cada vez hay una mayor aceptación de los bambúes para usos estructurales. Sin embargo, tienen como inconveniente su propensión al ataque por insectos. En este trabajo se hizo un estudio de la eficacia de tres diferentes tipos de preservadores: 1) químicos tradicionales, 2) naturales de bajo riesgo para el ser humano y 3) térmicos a diferentes temperaturas, para prevenir el ataque del insecto escarabajo Dinoderus minutus al bambú de la especie Bambusa vulgaris vittata. Los dos primeros tratamientos se realizaron por inmersión y el tipo térmico fue hecho por el proceso de secado. Cada dos semanas, se evaluó el ataque a tres especímenes de cada tratamiento, incluyendo los correspondientes a un testigo sin elemento preservador alguno. Los resultados mostraron que la mayoría de los tratamientos por inmersión fueron eficaces, reduciendo considerablemente el ataque de los insectos en comparación con el testigo.En cuanto al tratamiento térmico, las temperaturas menores o iguales a 130 °C no mostraron ser eficaces; las temperaturas de 190 °C y 210 °C revelaron eficacias aceptables.

The search for sustainable fuels has become important for the development of energy generation in balance with the environment. Brazil has climatic conditions and a vast territory for the production of forest biomass. The research produced in the laboratory determines the gravimetric yield, upper calorific value, percentages of fixed carbon, volatile and ashes of the charcoals of bamboo species: Bambusa vulgaris var vittatta, Dendrocalamus asper and Phyllostachys pubescens. For the carbonization process, small pieces of bamboo were obtained, were dried in the stove at 100°C for 24 hours, the dried mass was weighed and added in a carbonizer heated to 150°C for 45 minutes, heated to 180°C for 45 minutes and heated to 210°C for 30 minutes, this charcoal was then cooled and weighed to calculate the gravimetric yield. The samples were pulverized in a pot mill, the upper calorific value in a calorimeter was determined. The volatile, fixed carbon and ash contents were determined according to the Brazilian MB-15 method. The results obtained for the species B. vittatta, D. asper and P. pubescens, were respectively: gravimetric yield 44.08%, 42.77% and 47.09%; calorific value 28.806kJ/g, 29.075kJ/g and 28.489kJ/g; percentage of fixed carbon 62.1%, 66.09% and 57.8%; percentage of volatiles 35.89%, 30.92% and 40.4%; ash percentage 2.01%, 2.99% and 1.8%. It was observed that the D. asper specie presented better results in the general context of the analysis carried out because, despite presenting a slightly lower gravimetric yield, it presented the higher calorific value and higher fixed carbons content.

The aim of the present study was to investigate adhesion and biofilm formation on boning knife (new and used; handle – polyethylene and blade – stainless steel) surfaces to evaluate the efficiency of different concentrations of biguanide, peracetic acid and hot water (82.2 °C) in the removal of attached Escherichia coli cells on these surfaces. The bacteria presented an ability of biofilm formation in vitro , being weakly and moderately adherent after 6 h and 24 h respectively. Results showed that the bacterial adhesion increased with the time in both surfaces evaluated (handle and blade). Biofilm formation (1 × 10 3 CFU/cm 2 ) occurred after 6 h of contact time on the handles (new and used surfaces) and blades (new surface). A lower concentration (0.2%) of peracetic acid was efficient in removing adhered cells for 6 h on new and used surfaces. Hot water, typically used in industries, also proved to be efficient in most of the contact times evaluated. It was possible to observe that surface roughness increased with the bacterial adhesion. In this way, hot water with peracetic acid seems to be a promising treatment for the removal of E. coli from boning knives.

The objective of the present work was to study the use of bamboo foils as structural reinforcement for MDP wooden panels. Four wooden panels of homogeneous layer were produced using particles of GT1 and RRIM 600 clones ofHevea brasiliensis(rubber tree), and glued with urea-formaldehyde resin (UF). These panels were also overlaid with foils ofPhyllostachys edulis(mossô bamboo). The tests were realized to evaluate the physical-mechanical characterization according to European standards (EN). The production of the particleboards with reinforcement of bamboo improves the physical-mechanical characteristics of these commercial wooden panels.

The economic exploitation of rubber tree (Hevea brasiliensis) usage is primarily directed toward latex extraction. After the productive life of the rubber tree forest, the managed area is harvested for planting reformulation. The harvested wood is most often used for energy generation purposes. The aim of this work was to study the feasibility of using rubberwood waste and castor oil-based polyurethane resin in the production of particleboards. Homogeneous and heterogeneous panels were made with nominal dimensions of 500 x 500 mm and thicknesses of 10 mm using particles from GT1 and RRIM600 clones of the rubber tree and 12% castor oil-based polyurethane adhesive. The panels were pressed at 140 °C for 12 min with 40 kgf/cm2 specific pressure. Density, moisture content, thickness swelling, water absorption for 2 and 24 h, static bending, and internal bonding determinations were performed according to the Brazilian Standard (NBR) 14810-3 (2006) for the physical-mechanical panel characterization. The results show that using Hevea brasiliensis in particleboard production is viable. However, multilayer boards exhibited better results.

This study aimed to produce and determine physical and mechanical properties of three layers particleboards produced with Eucalyptus sp. particles, in outer layers, and Eucalyptus urograndis e Eucalyptus saligna bark, in internal layer. Recommendations of the Brazilian Code ABNT NBR 14810-3:2006 were adopted to fundament physical and mechanical tests. Properties considered were modulus of rupture (MOR) and modulus of elasticity (MOE) in static bending; internal adhesion; thickness swelling; water absorption; moisture content and density of the panels. Four different panel compositions were studied, with 5, 10, 15 and 20% of bark (related to particle mass) the internal layer. Results were compared with the requirements of: Brazilian Code ABNT NBR 14810-2; European Code EN 312 and related literature. The produced panels were adequate to all the values stipulated the cited codes and also superior to similar studies found in the literature, for all compositions of bark in internal layer, except for the moisture content test, in which only the composition of 5 % hull met the normative specifications.

Bamboo-based materials are in the toolbox of sustainable practices and have a high potential for the development and expansion of new products in the construction industry. Although uncountable advantages are attributed to bamboo, there are several problems related to its use that must be solved and mitigated. Without proper treatment, bamboo materials cannot withstand a long service life. The treatment procedures are already well-known, in which different methods and preservative solutions can be used depending on the final application, logistics, material condition, and affordability. Yet, necessary information about the chemical treatment of bamboo in terms of treatability, quality control, and the effect on physical-mechanical properties, and the development of less hazardous solutions are topics not adequately explored. Therefore, this doctorate thesis was divided into two major parts/objectives: assessment of conventional bamboo treatments and evaluation of alternative preservation methods based on chemical modification and in-situ polymerization. In the first part, conventional preservatives were applied for Dendrocalamus. asper and Phyllostachys edulis bamboo treatment and analysed in the quality aspects point of view. Analytical methods for treatability evaluation, such as penetration and retention, were used for disodium octaborate tetrahydrate (DOT) and chromate copper borate (CCB) treated bamboo. Mechanical, physical, and chemical tests were extensively used to characterize treated samples, and the effects of the preservatives on mechanical properties were investigated. Additionally, full-culm bamboo was object of detailed mechanical characterization through digital image correlation strain analysis. The obtained results led in recommendations for future standards for bamboo testing and the observation of the local effect of the node on compression, shear, tension, and bending. Besides, the investigated treatments did not show detrimental effects on the mechanical properties, yet DOT treatment causes an improvement in bamboo strength. Guidelines for treatment by the immersion method using DOT are also proposed to ensure the production quality of treated bamboo. In the second part of this thesis, pursuing the objective to improve the overall properties of bamboo, alternative treatment formulations based on citric acid and tannin in combination with boron compounds were tested. Samples chemically modified with citric acid presented considerable improvement on dimensional stability and decrease of water absorption as the consequence of an esterification process. However, the modification increased bamboo brittleness, reducing especially tension and bending strengths. The use of polymerized tannin/hexamine/boron had positive outcomes on the overall properties of bamboo, increasing the compression and bending strengths and the fungi degradation resistance even after leaching. Moreover, although DOT was effective in improving fungi decay resistance, severe leaching completely decreased its fungicide activity. Through thermogravimetric analyses, boron treated samples exhibited better thermal stability. In general, bamboo is a fascinating material. Nevertheless, although satisfactory treatment can be achieved, it is more difficult to be treated and characterised than wood. To overcome these problems, more research in characterization and treatment methods are necessary for better understanding and use of this abundant and versatile material. Os materiais à base de bambu estão na caixa de ferramentas de práticas sustentáveis e têm um alto potencial para o desenvolvimento e a expansão de novos produtos na indústria da construção. Embora inúmeras vantagens sejam atribuídas ao bambu, existem vários problemas relacionados ao seu uso que devem ser resolvidos e mitigados. Sem tratamento adequado, os materiais de bambu não resistem a uma longa vida útil. Os procedimentos de tratamento são bem conhecidos, para os quais diversos métodos e soluções preservativas podem ser utilizados, dependendo da aplicação final, logística, condição do material e acessibilidade. No entanto, informações básicas sobre o tratamento químico do bambu em termos de tratabilidade, controle de qualidade e o efeito nas propriedades físico-mecânicas e o desenvolvimento de soluções menos perigosas são tópicos pouco explorados. Portanto, esta tese de doutorado foi dividida em duas partes/objetivos principais: avaliação de tratamentos convencionais para bambu e o uso de métodos de preservação alternativos baseados em modificação química e polimerização in-situ. Na primeira parte, preservativos convencionais foram aplicados no tratamento dos bambus Dendrocalamus. asper e Phyllostachys edulis e analisados sob o ponto de vista de aspectos de qualidade. Métodos analíticos para avaliação da tratabilidade, como penetração e retenção, foram utilizados para o bambu tratado com octaborato de sódio tetrahidratado (OST) e cromato de cobre cromatado (CCB). Testes mecânicos, físicos e químicos foram amplamente utilizados para caracterizar amostras tratadas e os efeitos dos preservativos nas propriedades mecânicas foram investigados. Adicionalmente, o bambu roliço foi objeto de caracterização mecânica detalhada por meio de análise de deformação por correlação de imagem digital. Os resultados obtidos resultaram em recomendações para futuras normas para ensaios de bambu e na observação do efeito local do nó em compressão, cisalhamento, tração e flexão. Ademais, os tratamentos investigados não mostraram efeitos prejudiciais sobre as propriedades mecânicas, especialmente o tratamento com OST, que resulta em uma melhora na resistência do bambu. Diretrizes para tratamento pelo método de imersão usando OST também foram apresentadas como uma proposta para melhorar a qualidade da produção do bambu tratado. Na segunda parte desta tese, seguindo o objetivo de melhorar as propriedades gerais do bambu, foram testados tratamentos alternativos à base de ácido cítrico e tanino em combinação com compostos de boro. Amostras quimicamente modificadas com ácido cítrico apresentaram considerável melhora na estabilidade dimensional e diminuição da absorção de água como consequência de um processo de esterificação. No entanto, a modificação aumentou a fragilidade do bambu, reduzindo especialmente a resistência à flexão. O uso de tanino/hexamina/boro polimerizado apresentou resultados positivos nas propriedades gerais do bambu, aumentando as resistências à compressão e à tração na flexão e a resistência à degradação por fungos mesmo após a lixiviação. Embora o OST tenha sido eficaz para melhorar a resistência à decomposição de fungos, a lixiviação severa diminuiu completamente sua atividade fungicida. Contudo, por meio de análises termogravimétricas, as amostras tratadas com boro exibiram melhor estabilidade térmica. Em geral, o bambu é um material fascinante. No entanto, embora seja possível obter um tratamento satisfatório, é mais difícil de ser tratado e caracterizado do que a madeira. Para superar esses problemas, são necessárias mais pesquisas em métodos de caracterização e tratamento para melhor entendimento e uso desse abundante e versátil material.