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Fertilizer P fixation and fertilizer N losses in soils may be reduced through additions of polyphenolic compounds. The influence of ammonium lignosulfonate (NH$ sb4 sp+$-LS) on triple superphosphate (TSP) efficiency was investigated in a soil incubation study using three Quebec soils and in a growth bench study using one soil. For the incubation study, soils were analyzed for pH and P extractability, as a function of NH$ sb4 sp+$-LS rate and time. In the growth bench study, TSP and NH$ sb4 sp+$-LS were applied at varying rates and corn (Zea mays L.) dry matter yields and nutrient compositions analyzed. Similar studies were conducted in subsequent growth bench studies, to evaluate combinations of NH$ sb4 sp+$-LS, diammonium phosphate (DAP), and urea on two soils. / Ammonium LS increased soluble P levels when applied with TSP. The effect was most significant in fine textured soils, and increased with time. This improved P availability to plants, without affecting growth. The optimum NH$ sb4 sp+$-LS:P$ sb2$O$ sb5$ application ratio was approximately 2.8:1. Ammonium LS did not improve availability of DAP-P in either of the subsequent experiments, nor did it improve urea fertilizer efficiency. Some NH$ sb4 sp+$-LS-urea-DAP formulations did, however, improve corn growth beyond that obtained when only urea and DAP were applied in combination. In nutrient amended soils, applying NH$ sb4 sp+$-LS DAP was detrimental to growth and, for some application rates, reduced nutrient uptake.

Chitin is a polysaccharide found in abundance in the shell of crustaceans. In this study, chitin was first extracted from shrimp waste material previously demineralized, using proteolytic enzymes, i.e., chymotrypsin and papain. The conditions used for the deproteinization were optimized with respect to 3 factors, viz., pH, temperature, and enzyme to waste (E/W) ratio, using response surface methodology (RSM). / In a second part of the study, chitosan was prepared from chitin by partial deacetylation and its capacity to preserve whole and headless fresh shrimps was evaluated. The shrimps (Pandalus borealis) were dipped in chitosan (1 and 2% w:v), and stored on ice. Chemical indicators such as pH, drip loss, total volatile bases (TVB), nucleotide degradation, and sensory indicators of appearance (including melanosis) and odor, as well as total microbial counts were monitored during 20 days. / As a third and final part, the antimicrobial properties of chitosan were evaluated using several microorganisms implicated in food spoilage and/or food poisoning outbreaks, especially those associated with fish and seafood products. Chitosan prepared from crab offal and used in the previous study on shrimp preservation was compared with commercially available chitosan from Sigma Chemical Co. (St-Louis, MO). (Abstract shortened by UMI.)

Lignosulfonate (LS), a by-product of the pulp and paper industry, may have the potential to increase fertilizer N availability by acting as a urease and nitrification inhibitor. Four consecutive laboratory studies were conducted to evaluate the behavior of LS in agricultural soils. The effects of various types and rates of LS on soil respiration and soil N dynamics were determined. Effects of LS in combination with fertilizers on microbial activity and N dynamics were measured. Due to the high water solubility of LS a leaching column study was conducted to determine the potential leaching of LS. / Higher rates (20% w/w) of LS initially inhibited microbial activity. Generally LS was relatively resistant to degradation by soil microorganisms and small proportions of added LS-C ($<$2.1%) were leached from the soil columns, but leaching was a function of soil and moisture regime. Recovery of added mineral LS-N from soil treated with LS was low ($<$41%). Mineral N recovered from LS plus fertilizer amended soil was higher than recovery from corresponding fertilizer treatments. Lignosulfonate reduced urea hydrolysis and the proportion of added N volatilized as NH$ sb3$-N from a LS plus urea treatment. The mineral N pool from LS plus fertilizer treated soils had significantly lower NO$ sb3$-N concentrations than corresponding fertilizer treatments. Nitrification inhibition was believed to have been due to high fertilizer concentrations. At reduced urea and LS concentrations, LS decreased NO$ sb3$-N recovery in one of four soil types. However, reduced recovery may not have been from nitrification inhibition but possibly from denitrification or chemical reactions between N and phenolics from LS.

Orientador: Raphael Lucio Andreatti Filho / Banca: Teresinha Knobl / Banca: José Paes de Almeida Nogueira Pinto / Resumo: O biofilme representa uma importante fonte de contaminação de alimentos, podendo estar presente em vários pontos da cadeia de processamento da carne de frango. O controle do biofilme na indústria alimentícia necessita de métodos alternativos, a fim de superar a resistência a desinfetantes comuns e garantir um alimento livre de resíduos químicos. Os objetivos deste estudo foram avaliar a influência das superfícies de inox, vidro e PVC sobre a formação de biofilmes de Salmonella spp. em diferentes momentos, e avaliar a ação lítica de um pool de bacteriófagos sobre biofilmes destas bactérias. A maioria das amostras foi classificada como fracas produtoras de biofilme, e os sorovares Heidelberg e Enteritidis apresentaram um número significativamente maior de amostras formadoras. As superfícies de inox e vidro favoreceram significativamente a formação de biofilme em três e cinco períodos, respectivamente. O pool de bacteriófagos reduziu a formação de biofilme nas superfícies de inox, vidro e PVC, e seu período de ação concentrou-se principalmente em 3h, porém estes resultados não foram estatisticamente significantes. Nossos achados sugerem que o sorovar e a superfície envolvidos podem interferir significativamente na produção de biofilme, porém através dos métodos utilizados neste estudo, não podemos confirmar a ação de bacteriófagos sobre biofilmes de Salmonella spp. nas superfícies de vidro, inox e PVC / Abstract: Biofilm is a major source of food contamination and may be present in various parts of the chicken meat processing chain. The control of biofilm in the food industry needs alternative methods in order to overcome resistance to disinfectants and ensure food free of chemical residues. The objective of this study was to evaluate the influence of the surfaces of stainless steel, glass and PVC in the biofilm formation by Salmonella spp. at different times and evaluate the action of a pool of bacteriophages against this bacterial biofilms. Most samples were classified as weak biofilm producers. Heidelberg and Enteritidis serotypes showed a significantly higher number of samples capable to produce biofilm. The surfaces of stainless steel and glass significantly favored the biofilm formation in three and five periods, respectively. The bacteriophage pool reduced biofilm formation on the surfaces of stainless steel, glass and PVC and its action period focused mainly at 3h. Our findings suggests that there is a difference in the production of biofilms by different serotypes of Salmonella spp., as well as significantly interference of the surfaces in the production of biofilms by this bacteria, however more studies should be conducted in order to characterize the bacteriophage action in the control of biofilms / Mestre

Made available in DSpace on 2015-12-10T14:24:03Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-06-02. Added 1 bitstream(s) on 2015-12-10T14:28:09Z : No. of bitstreams: 1 000849378.pdf: 472287 bytes, checksum: 106ccaa9a768ad6734e5c325b2277ff2 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O biofilme representa uma importante fonte de contaminação de alimentos, podendo estar presente em vários pontos da cadeia de processamento da carne de frango. O controle do biofilme na indústria alimentícia necessita de métodos alternativos, a fim de superar a resistência a desinfetantes comuns e garantir um alimento livre de resíduos químicos. Os objetivos deste estudo foram avaliar a influência das superfícies de inox, vidro e PVC sobre a formação de biofilmes de Salmonella spp. em diferentes momentos, e avaliar a ação lítica de um pool de bacteriófagos sobre biofilmes destas bactérias. A maioria das amostras foi classificada como fracas produtoras de biofilme, e os sorovares Heidelberg e Enteritidis apresentaram um número significativamente maior de amostras formadoras. As superfícies de inox e vidro favoreceram significativamente a formação de biofilme em três e cinco períodos, respectivamente. O pool de bacteriófagos reduziu a formação de biofilme nas superfícies de inox, vidro e PVC, e seu período de ação concentrou-se principalmente em 3h, porém estes resultados não foram estatisticamente significantes. Nossos achados sugerem que o sorovar e a superfície envolvidos podem interferir significativamente na produção de biofilme, porém através dos métodos utilizados neste estudo, não podemos confirmar a ação de bacteriófagos sobre biofilmes de Salmonella spp. nas superfícies de vidro, inox e PVC / Biofilm is a major source of food contamination and may be present in various parts of the chicken meat processing chain. The control of biofilm in the food industry needs alternative methods in order to overcome resistance to disinfectants and ensure food free of chemical residues. The objective of this study was to evaluate the influence of the surfaces of stainless steel, glass and PVC in the biofilm formation by Salmonella spp. at different times and evaluate the action of a pool of bacteriophages against this bacterial biofilms. Most samples were classified as weak biofilm producers. Heidelberg and Enteritidis serotypes showed a significantly higher number of samples capable to produce biofilm. The surfaces of stainless steel and glass significantly favored the biofilm formation in three and five periods, respectively. The bacteriophage pool reduced biofilm formation on the surfaces of stainless steel, glass and PVC and its action period focused mainly at 3h. Our findings suggests that there is a difference in the production of biofilms by different serotypes of Salmonella spp., as well as significantly interference of the surfaces in the production of biofilms by this bacteria, however more studies should be conducted in order to characterize the bacteriophage action in the control of biofilms / FAPESP: 2013/07129-9

O aumento da produção e abate de aves vem ao encontro da responsabilidade de destinação adequada dos resíduos de abatedouros. Pressionadas ainda pelas legislações e políticas ambientais e pelas oportunidades de negócio foram criadas as indústrias de processamento de subprodutos de origem animal, conhecidas como “graxarias”, que processam estes resíduos transformando-os em farinhas de alto valor agregado utilizadas na composição de rações. Porém, a grande variação na composição das matérias-primas e a falta de padronização do processo de fabricação são consideradas os maiores desafios para o uso desses alimentos como ingredientes de rações. O presente trabalho teve como objetivo otimizar o processo de fabricação de farinha de penas, visando o aumento do teor protéico (TP) e do valor de digestibilidade (VD), bem como determinar as variáveis e os níveis que potencialmente podem influenciar no processo de obtenção da farinha. A parte experimental deste trabalho está apresentada em três capítulos: No capítulo 1 avaliou-se a variabilidade do TP e do VD da farinha de penas de frango e peru em função dos parâmetros do processo. Observou-se uma grande dificuldade na padronização da farinha de penas contendo penas de frango e de peru. A pressão e o tempo de hidrólise diferiram entre as matérias-primas. Tanto a variável pressão como o tempo de hidrólise influenciaram no TP e no VD. Os resultados mais elevados foram obtidos para a farinha composta por 100% penas de frango. No capítulo 2 avaliou-se a Influência da etapa de pré-secagem no TP e no VD da farinha de penas. Foram utilizados planejamento fatorial e metodologia de superfície de resposta para avaliar essa influência. A pressão, tempo de hidrólise, tempo de pré-secagem e composição de diferentes matérias primas foram determinadas como variáveis independentes, enquanto as variáveis respostas foram TP e VD. O aumento no tempo de pré-secagem foi significativo (p<0,05) para elevar as variáveis. A inclusão de penas de peru foi significativa (p<0,05) na obtenção de farinha de penas, representando uma redução tanto nos resultados do TP como no VD das farinhas. No capítulo 3 avaliou-se a influência da adição de diferentes percentuais de sangue sobre as variáveis respostas, TP e VD, da farinha de penas. Foi utilizado planejamento fatorial e metodologia de superfície de resposta para avaliar essa influencia. As variáveis independentes foram pressão, tempo de hidrólise, matéria-prima e adição de sangue. O maior TP obtido foi através da dosagem de 20% de sangue para as duas matérias-primas. Os níveis das variáveis de processo com os quais se obteve os mais elevados TP (84,56%) e VD (47,96%) foram com 2,5 kgf.cm-2 de pressão e 40 min. de hidrólise. O aumento no percentual de sangue e no tempo de hidrólise foi significativo (p<0,05) para aumentar tanto o TP como o VD da farinha de penas. Com a incorporação de penas de peru ocorreu uma redução significativa (p<0,05) no TP e no VD das farinhas. / The increased poultry production and slaughtering encounters the responsibility of proper disposal of waste from slaughterhouses. Pressed further by legislation and environmental policies and the business opportunities were created industries processing animal by-products, known as "graxarias" which process these waste transforming them into high value-added flours used in feed composition. However, the wide variation in the composition of the raw materials and the lack of standardization of the manufacturing process are considered the major hallenges for the use of these foods as ingredients of rations. This study aimed to optimize the manufacturing process of feather meal, in order to increase the protein content (PC) and digestibility value (DV), and to determine the variables and levels that can potentially influence the process of flour obtaining. The experimental part of this work is presented in three chapters: the first chapter we evaluated the variability of TP and RV feather meal of chicken and turkey as a function of process parameters. There is a great difficulty in the standardization of feather meal containing chicken feathers and turkey. The pressure and time of hydrolysis differed among the raw materials. Both the variable pressure as the hydrolysis time affected in PC and DV. The highest scores were obtained for 100% flour made of chicken feathers. In chapter 2 we evaluated the influence of pre-drying step in PC and DV feather meal. We used a factorial design and response surface methodology to assess this effect. The pressure, hydrolysis time, length of pre-drying and composition of different raw materials were determined as independent variables, while the variables were PC and DV. The increase in the pre-drying time was significant (p<0,05) to increase the variables. The inclusion of turkey feathers was significant (p<0,05) in obtaining feather meal, a reduction in both the results of TP as in RV flours. In chapter 3 we evaluated the effect of adding different percentages of blood on the response variables, PC and DV, feather meal. We used a factorial design and response surface methodology to assess this influence. The independent variables were pressure, hydrolysis time, raw material and adding blood. The higher PC was obtained by measuring blood of 20% for the two raw materials. The levels of the process variables which are obtained with the highest TP (84,56%) and VD (47,96%) was 2,5 kgf.cm-2 pressure and 40 min. hydrolysis. The increase in the percentage of blood and the hydrolysis time was significant (p<0,05) increase both the PC and DV as feather meal. With the incorporation of turkey feathers there was a significant reduction (p<0,05) in PC and DV flours.

Com o crescimento do consumo de produtos processados de peru, conhecer o impacto dos defeitos causados pela matéria prima tornou-se muito importante. Foram testadas duas formulações, uma utilizando como matéria prima carne de peito de peru ácida e outra com carne normal, utilizando como parâmetros para carne ácida pH < 5,67 e carne normal pH >5,72 e o restante dos ingredientes e processo foram idênticos. A partir do produto já cozido, foram preparados embalagens a vácuo com duas fatias de aproximadamente 100g cada um e deixados estocados por um período de 40 dias, após este período foram realizados testes de composição proximal, pH, CRA (capacidade de retenção de água), e gotejamento. Em nenhum dos resultados foram detectadas diferenças significativas entre as amostras avaliadas, mostrando que a adição de ingredientes tecnológicos como proteína de soja, carragena, fécula de mandioca e fosfatos foram capazes corrigir os efeitos do uso de carne de peru ácida, melhorando sua qualidade, reduzindo a perda de líquido, padronizando sua coloração, melhorando sua textura ou aumentando sua vida de prateleira. / With the growing consumption of processed turkey products, knowing the impact of defects caused by the raw material has become very important. Two formulations for production of turkey stuffed product were tested using regular raw meat and other acid turkey meat. For normal acid breast meat was used parameters pH < pH 5.67 and standard meat pH> 5.72 and the remainder of the ingredients and process were identical for both. 30 samples of two slices of cooked turkey built approximately 100g each were vacuum packed and left stored for a period of 40 days at 4 ºC. Then, tests of proximal composition , pH, water retention capacity and dripping were made. No significant differences between the results analyzed samples were detected , showing that the addition of technological ingredients such as soy protein, carrageenan , tapioca starch and phosphate were able to inhibit any defects of use acid meat.

Com o crescimento do consumo de produtos processados de peru, conhecer o impacto dos defeitos causados pela matéria prima tornou-se muito importante. Foram testadas duas formulações, uma utilizando como matéria prima carne de peito de peru ácida e outra com carne normal, utilizando como parâmetros para carne ácida pH < 5,67 e carne normal pH >5,72 e o restante dos ingredientes e processo foram idênticos. A partir do produto já cozido, foram preparados embalagens a vácuo com duas fatias de aproximadamente 100g cada um e deixados estocados por um período de 40 dias, após este período foram realizados testes de composição proximal, pH, CRA (capacidade de retenção de água), e gotejamento. Em nenhum dos resultados foram detectadas diferenças significativas entre as amostras avaliadas, mostrando que a adição de ingredientes tecnológicos como proteína de soja, carragena, fécula de mandioca e fosfatos foram capazes corrigir os efeitos do uso de carne de peru ácida, melhorando sua qualidade, reduzindo a perda de líquido, padronizando sua coloração, melhorando sua textura ou aumentando sua vida de prateleira. / With the growing consumption of processed turkey products, knowing the impact of defects caused by the raw material has become very important. Two formulations for production of turkey stuffed product were tested using regular raw meat and other acid turkey meat. For normal acid breast meat was used parameters pH < pH 5.67 and standard meat pH> 5.72 and the remainder of the ingredients and process were identical for both. 30 samples of two slices of cooked turkey built approximately 100g each were vacuum packed and left stored for a period of 40 days at 4 ºC. Then, tests of proximal composition , pH, water retention capacity and dripping were made. No significant differences between the results analyzed samples were detected , showing that the addition of technological ingredients such as soy protein, carrageenan , tapioca starch and phosphate were able to inhibit any defects of use acid meat.

Please read the abstract in the section 00front of this document / Dissertation (MSc (Soil Science))--University of Pretoria, 2007. / Plant Production and Soil Science / unrestricted