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The Relative Roles of Initial and Residual Sodium Nitrite on Germination of Clostridium botulinam Spores in MeatMettanant, Orchid 01 May 1982 (has links)
Four levels of NaNO2 (0 ppm, 50 ppm, 100 ppm, and 156 ppm) were tested for antibotulinal activity in ground pork inoculated with spores of Clostridium botulinum either at the time of formulation or after cooking. Samples formulated with less than 156 ppm sodium nitrite received additional nitrite to adjust the residual nitrite equal to that found after cooking in samples formulated with 156 ppm nitrite. All samples were subjected to abusive storage at 27 C. Inoculating the spores at the time of formulation resulted in a faster rate of swelling. Heating C. botulinum spores for 30 min. at 77 C before addition to cooked meat also resulted in rapid germination. Total botulinal counts were significantly higher (p=0.05) in these samples, compared with similarly treated samples formulated with unheated spores.
Samples formulated with 50 ppm initial sodium nitrite and with 78 ppm additional NaNO2 after cooking were the most inhibitory. Initial nitrite concentration was shown to be important for inhibition of C. botulinum growth, probably because of the inhibitory carryover effects of protein-bound nitrite formed during cooing, as well as influencing the concentration of residual nitrite.
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Omeprazol atenua os efeitos anti-hipertensivos do nitrito de sódio em ratos / Omeprazole Attenuates the antihypertensive effect of sodium nitrite in ratsPinheiro, Lucas Cézar, 1986- 08 January 2011 (has links)
Orientador: José Eduardo Tanus dos Santos / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-18T18:14:31Z (GMT). No. of bitstreams: 1
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Previous issue date: 2011 / Resumo: O óxido nítrico (NO) regula diversos sistemas orgânicos. Disfunções na produção ou disponibilidade de NO podem comprometer sua atuação fisiológica. Além da produção de NO pelas óxido nítrico sintetases, outras vias de produção de NO são relatadas, entre elas a conversão de nitrito a NO. O nitrito é o produto inicial da oxidação do NO, sendo posteriormente oxidado a nitrato. Sabe-se que estas três moléculas formam um ciclo dentro do organismo. A conversão de nitrito a NO pode ocorrer de forma enzimática ou não enzimática. Como forma não enzimática, o nitrito é convertido a NO pela reação com H+. Esta reação ocorre principalmente no estômago, todavia não se sabe se este NO formado tem efeito na pressão arterial sistêmica ou atua apenas localmente. A fim de verificar a influência do pH gástrico no efeito hipotensor do nitrito de sódio, utilizamos animais tratados agudamente com LNAME e normotensos canulados acordados pré-tratados com omeprazol e, posteriormente, com nitrito de sódio 15mg/kg e 45mg/kg. Foi verificado que o nitrito de sódio reduz a pressão arterial média dos animais significativamente e de maneira dependente da dose. O pré-tratamento com omeprazol reduziu o efeito hipotensor do nitrito de sódio significativamente. Após, foram quantificados os níveis de nitrito e nitrato. Foi observado aumento em ambos após o tratamento com nitrito de sódio. A partir destes resultados podemos sugerir que o omeprazol atenua o efeito hipotensor do nitrito de sódio em ratos normotensos e hipertensos / Abstract: Many body systems are regulated by nitric oxide (NO). Dysfunctions in the production or availability of NO may impair it physiological roles. However, other routes of NO production are reported in addition to NO production by nitric oxide synthases, including the conversion of nitrite to NO. Nitrite is the initial product of oxidation of NO and is further oxidized to nitrate. It is known that these three molecules form a cycle within the body. The conversion of nitrite to NO can occur enzymatic or nonenzymatic. Non-enzymatic nitrite is converted to NO by reacting with H+. This reaction occurs mainly in the stomach, however it is unclear whether this NO affects blood pressure or simply acts locally. To study the influence of gastric pH on the hypotensive effect of sodium nitrite, we used hypertensive or normotensive cannulated animals pretreated with omeprazole and with sodium nitrite 15 mg/kg and 45 mg/kg. We found that sodium nitrite reduces mean arterial pressure of animals in a dose-dependent manner. Pretreatment with omeprazole reduced the hypotensive effect of sodium nitrite significantly. Thereafter, we quantified the levels of nitrite and nitrate. We found increase in both species after treatment with sodium nitrite. These results suggest that omeprazole attenuates the hypotensive effect of sodium nitrite in normotensive and hypertensive rats / Mestrado / Farmacologia / Mestre em Farmacologia
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The responses of lymphocytes from Asian and Caucasian diabetic patients and non-diabetics to hydrogen peroxide and sodium nitrite in the Comet assayAnderson, Diana, Fontana, V., Kelly, C., Wyatt, N.P., Merlo, D.F. January 2006 (has links)
No / Numerous factors may influence the incidence of diabetes in the population. The production of reactive oxygen species (ROS) is elevated in diabetes patients. Based on the reported involvement of reactive species and nitrate/nitrite in diabetes, this present study has examined in the alkaline Comet assay, the effect of different levels of NaNO2 in the presence of the oxygen radical generating agent, hydrogen peroxide (H2O2). Peripheral lymphocytes from diabetic and non-diabetic Caucasians and Asians of both sexes were studied in vitro. Endogenous factors (e.g., sex, age, body mass index-BMI) and exogenous factors (lifestyle factors e.g., smoking and drinking habits, diet) were taken into account. A preliminary study in two individuals showed that DNA damage remained constant over a wide dose range of NaNO2 (1-75 mM), but when H2O2 was added at a constant concentration of 50 ¿M per dose of NaNO2, there was an increase in DNA damage corresponding with the varying levels of NaNO2 investigated. This was also seen with the 44 individuals (non-diabetic, n = 24; type 1 diabetic, n = 11; type 2 diabetic, n = 9) investigated. NaNO2 was capable of inducing a significant level of DNA damage in lymphocytes (p<0.001), but only with the addition of H2O2. When levels of DNA damage were analysed in terms of the different variables there were few significant differences in damage between diabetic and non-diabetic subjects, or other sub-population groups, and no statistically significant differences in susceptibility were observed between subject covariates using regression techniques.
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Effect of intrinsic factors on growth of listeria monocytogenes in sliced deli turkey.Roenbaugh, Tawnya Leigh January 1900 (has links)
Master of Science / Food Science Institute / Elizabeth Boyle / Intrinsic factors impact Listeria monocytogenes growth in ready-to-eat poultry products. Sliced deli turkey was formulated with in-going concentrations of 1.5% NaCl or 0.75% NaCl/0.75% KCl, 0 ppm or 200 ppm NaNO[subscript]2, and using 10% or 45% pump for a total of 8 treatments. Turkey roasts were sliced and inoculated with a 5-strain L. monocytogenes cocktail or peptone water (control), vacuum packaged, and stored at 4[degree]C. Treatments were sampled on days 0, 7, 14, 21, 28, 42, 63, and 91 of storage to determine L. monocytogenes mean log growth and aerobic plate count (APC). The pH, water activity, residual nitrite concentration, and percent fat, moisture, protein, and sodium were measured using control treatments on each sampling day. There was a nitrite by day and a percent pump by day interaction (P<0.05) for L. monocytogenes and APC populations. Listeria monocytogenes populations in treatments containing 200 ppm NaNO[subscript]2 were 0.70 to 2.39 log CFU/cm[superscript]2 lower compared with products formulated with 0 ppm NaNO[subscript]2. Using 10% pump reduced L. monocytogenes populations by 0.62 to 1.50 log CFU/cm[superscript]2 on days 7 to 28 and at day 63 compared with 45% pump treatments. Incorporating 1.5% NaCl or 0.75% NaCl/0.75% KCl into formulations did not affect (P>0.05) L. monocytogenes populations during storage. On days 7 through 91, APC populations were 0.76 to 2.96 log CFU/cm[superscript]2 lower with inclusion of 200 ppm NaNO[subscript]2 compared to 0 ppm NaNO[subscript]2. There was a treatment by day interaction (P<0.05) for L. monocytogenes populations and APC. The initial inoculum level of L. monocytogenes averaged 2.21 log CFU/cm[superscript]2 and was similar (P>0.05) for all treatments on day 0. Listeria monocytogenes populations increased (P<0.05) from day 0 to 14 by 1.30 to 5.04 log CFU/cm[superscript]2. Overall, L. monocytogenes populations increased during storage and by day 91 L. monocytogenes populations were similar regardless of NaNO[subscript]2 level used except for treatments formulated with 0.75% NaCl/0.75% KCl and 10% pump. Listeria monocytogenes and APC populations were influenced by nitrite concentration and percent pump, while inclusion of NaCl or NaCl/KCl did not affect L. monocytogenes growth during refrigerated storage in vacuum packed sliced deli turkey.
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Nitrite conversion to nitric oxide biological mechaisms and therapeutic implications /Isbell, T. Scott January 2007 (has links) (PDF)
Thesis (Ph.D.)--University of Alabama at Birmingham, 2007. / Title from PDF title page (viewed on Feb. 4, 2010). Includes bibliographical references (p. 120-131).
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Efeitos do nitrito de sódio e sua associação ao sildenafil na hipertensão gestacional experimental em ratasRizzi, Victor Hugo Gonçalves. January 2018 (has links)
Orientador: Carlos Alan Candido Dias Junior / Resumo: As desordens hipertensivas gestacionais são complicações que acometem em torno de 5-10% das gestações. Essas desordens são as maiores causas de morbidade e mortalidade tanto materna quanto fetal. Estudos demonstram redução da biodisponibilidade do óxido nítrico (NO) em doenças hipertensivas gestacionais, tornando uma das condições responsáveis por agravar a disfunção endotelial durante o curso desta doença. Neste sentido, trabalhos demonstram que a administração oral de nitrito de sódio (NaNO2) e a administração de citrato de sildenafil podem reverter a redução da biodisponibilidade de NO e potencializar a via de sinalização NO-GMPc respectivamente. Para realização dos trabalhos foram utilizadas ratas Wistar, no qual, após confirmação da prenhez receberam L-NAME i.p para indução da hipertensão e tratamentos com nitrito de sódio e/ou citrato de sildenafil via oral entre os dias 14-21 de prenhez. A pressão arterial sistólica foi aferida pelo método de pletismografia de cauda. Parâmetros materno-fetais como: peso fetal e placentário, número de fetos viáveis e reabsorvidos foram realizados após a morte das ratas no 21º dia gestacional. O plasma das ratas foram armazenados para dosagens dos níveis plasmáticos de nitrito+nitrato, guanosina monofosfato cíclico (GMPc), mieloperoxidase (MPO), peroxidação lipídica (TBARS), TEAC, MTT sFlt-1 e VEGF. Além disso o plasma das ratas foram incubadas com células endoteliais de cordão umbilical humano (HUVECS) para avaliar a produção de NO endo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Gestational hypertensive disorders are complications that affect around 5-10% of pregnancies. These disorders are the major causes of both maternal and fetal morbidity and mortality. Studies have demonstrated a reduction in the bioavailability of nitric oxide (NO) in gestational hypertensive diseases, making it one of the conditions responsible for aggravate the endothelial dysfunction during the course of this disease. In this sense, studies demonstrate that oral administration of sodium nitrite (NaNO2) and administration of sildenafil citrate may reverse the reduction of NO bioavailability and potentiate the NO-cGMP signaling pathway, respectively. Wistar rats were used to perform the study, in which, after confirmation of pregnancy, they received L-NAME i.p for induction of hypertension and treatments with sodium nitrite and/or sildenafil citrate orally between days 14-21 of pregnancy. Systolic blood pressure was measured by the tail plethysmography method. Maternal-fetal parameters such as: fetal and placental weight, number of viable and reabsorbed fetuses were performed after the death of the rats on the 21st gestational day. Plasma of the rats were stored for plasma levels of nitrite + nitrate, cGMP, myeloperoxidase (MPO), lipid peroxidation (TBARS), TEAC, MTT sFlt-1 and VEGF. In addition the plasma of the rats were incubated with human umbilical vein endothelial cells (HUVECS) to evaluate endothelial NO production. In both studies, we found reduction of systolic blood... (Complete abstract click electronic access below) / Doutor
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Efeitos do nitrito de sódio e sua associação ao sildenafil na hipertensão gestacional experimental em ratas / Effects of sodium nitrite and its association with sildenafil in experimental gestational hypertension in ratsRizzi, Victor Hugo Gonçalves 26 February 2018 (has links)
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Previous issue date: 2018-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / As desordens hipertensivas gestacionais são complicações que acometem em torno de 5-10% das gestações. Essas desordens são as maiores causas de morbidade e mortalidade tanto materna quanto fetal. Estudos demonstram redução da biodisponibilidade do óxido nítrico (NO) em doenças hipertensivas gestacionais, tornando uma das condições responsáveis por agravar a disfunção endotelial durante o curso desta doença. Neste sentido, trabalhos demonstram que a administração oral de nitrito de sódio (NaNO2) e a administração de citrato de sildenafil podem reverter a redução da biodisponibilidade de NO e potencializar a via de sinalização NO-GMPc respectivamente. Para realização dos trabalhos foram utilizadas ratas Wistar, no qual, após confirmação da prenhez receberam L-NAME i.p para indução da hipertensão e tratamentos com nitrito de sódio e/ou citrato de sildenafil via oral entre os dias 14-21 de prenhez. A pressão arterial sistólica foi aferida pelo método de pletismografia de cauda. Parâmetros materno-fetais como: peso fetal e placentário, número de fetos viáveis e reabsorvidos foram realizados após a morte das ratas no 21º dia gestacional. O plasma das ratas foram armazenados para dosagens dos níveis plasmáticos de nitrito+nitrato, guanosina monofosfato cíclico (GMPc), mieloperoxidase (MPO), peroxidação lipídica (TBARS), TEAC, MTT sFlt-1 e VEGF. Além disso o plasma das ratas foram incubadas com células endoteliais de cordão umbilical humano (HUVECS) para avaliar a produção de NO endotelial. Em ambos os trabalhos, nós encontramos redução da pressão arterial sistólica com nitrito e sildenafil, tanto isolado quanto em associação. Somente o sildenafil foi capaz de aumentar o peso fetal, enquanto o peso placentário foi melhorado por ambas as drogas. Tanto nitrito quanto sildenafil foram capaz de reduzir a reabsorção, possivelmente por aumentar a viabilidade fetal. Foi encontrado aumento de NO plasmático em todos os grupo que receberam nitrito, enquanto curiosamente a síntese de NO em HUVECS incubadas com plasma das ratas foi aumentada em ambas as drogas. Ainda em relação a cultura celular, nós encontramos aumento da viabilidade celular em ratas hipertensas tratadas com sildenafil. A concentração plasmática de GMPc estava aumentada em ratas normotensos que receberam sildenafil. Ambas as drogas apresentam efeito antioxidante, mas somente o sildenafil foi capaz de reduzir a atividade plasmática da MPO. Fatores angiogênicos (VEGF) e anti-angiogênicos (sFlt-1) presentes em doenças hipertensivas gestacionais estavam aumentados em ratas que receberam L-NAME, porém o nitrito de sódio foi capaz de reduzir esses fatores. Nosso dados sugerem que o nitrito e o sildenafil, tanto isolado 2 quanto em associação apresentam efeitos anti-hipertensivos e antioxidantes. Portanto, nossos resultados sugerem que a ativação da via NO-GMPc aumentou o fluxo sanguíneo na interface materno-fetal e protegeu contra a hipertensão e a restrição do crescimento fetal induzidas pelo L-NAME. / Gestational hypertensive disorders are complications that affect around 5-10% of pregnancies. These disorders are the major causes of both maternal and fetal morbidity and mortality. Studies have demonstrated a reduction in the bioavailability of nitric oxide (NO) in gestational hypertensive diseases, making it one of the conditions responsible for aggravate the endothelial dysfunction during the course of this disease. In this sense, studies demonstrate that oral administration of sodium nitrite (NaNO2) and administration of sildenafil citrate may reverse the reduction of NO bioavailability and potentiate the NO-cGMP signaling pathway, respectively. Wistar rats were used to perform the study, in which, after confirmation of pregnancy, they received L-NAME i.p for induction of hypertension and treatments with sodium nitrite and/or sildenafil citrate orally between days 14-21 of pregnancy. Systolic blood pressure was measured by the tail plethysmography method. Maternal-fetal parameters such as: fetal and placental weight, number of viable and reabsorbed fetuses were performed after the death of the rats on the 21st gestational day. Plasma of the rats were stored for plasma levels of nitrite + nitrate, cGMP, myeloperoxidase (MPO), lipid peroxidation (TBARS), TEAC, MTT sFlt-1 and VEGF. In addition the plasma of the rats were incubated with human umbilical vein endothelial cells (HUVECS) to evaluate endothelial NO production. In both studies, we found reduction of systolic blood pressure with nitrite and sildenafil, both alone and in combination. Both nitrite and sildenafil were able to reduce reabsorption, possibly by increasing fetal viability. No increase in plasma NO was found in all groups receiving nitrite, while curiously NO synthesis in HUVECS incubated with plasma from rats was increased in both drugs. Still in relation to cell culture, we found increased cell viability in hypertensive rats treated with sildenafil. Plasma cGMP concentration was increased in normotensive rats receiving sildenafil. Both drugs have an antioxidant effect, but only sildenafil was able to reduce plasma myeloperoxidase activity (MPO). Angiogenic (VEGF) and anti-angiogenic (sFlt-1) factors present in gestational hypertensive diseases were increased in rats receiving L-NAME, but sodium nitrite was able to reduce these factors. Our data suggest that both nitrite and sildenafil, both alone and in combination, have antihypertensive and antioxidant effects. Therefore, our results suggest that activation of the NO-cGMP pathway increased blood flow at the maternal-fetal interface and protected against hypertension and fetal growth restriction induced by L-NAME. / FAPESP 16/18782-3 / FAPESP 12/21305-1
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Influência da redução do teor de nitrito de sódio na estabilidade oxidativa e avaliação microbiológica de linguiça suína frescal / Influence of reduction in the sodium nitrite content on oxidation stability and microbiological evaluation of fresh pork sausageFigueiró, Lorane Sarmento 28 August 2013 (has links)
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Previous issue date: 2013-08-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The processing of cured meat products involves some chemical preservatives such as sodium nitrite aiming to preserve, modify sensory traits and diversify production. Addition of nitrite has been associated with a negative image as regards the health of consumers due to the formation of nitrosamine, which has led the food industry to reconsider the amount of nitrite used. Given this scenario, the objective of this study was to evaluate the influence of the sodium nitrite concentration on the oxidation stability and microbiological count of fresh pork sausage. Sausage samples containing 0, 50, 100, 150 and 200 mg.kg-1 sodium nitrite were prepared, vacuum-packed and stored at 5 ºC. We evaluated the lipid oxidation profile, by the number of substances reactive to thiobarbituric acid (TBARS), color, pH, acidity and quantification of residual nitrite throughout the storage period (Days 1, 8 and 15). The microbiological evaluation was performed by counting the total coliforms (NMP.g-1); thermo-tolerant coliforms (NMP.g-1), psychrotrophic microorganisms (Log.cfu.g-1) and coagulase-positive Staphylococcus (cfu.g-1) on days 0, 7 and 14. During the studied period, a TBARS of 0.24 mg.kg-1 was observed when 50 mg.kg-1 nitrite were added, and 0,09 mg.kg-1 when we utilized 200 mg.kg-1, displaying a decrease (P ≤ 0.05) in the number of TBARS as the sodium nitrite concentration was elevated. During the storage time, an increase (P ≤ 0.05) from 0.14 mg.kg-1 to 0.21 mg.kg-1 was observed in TBARS, demonstrating development of the lipid-peroxidation process. With regard to the objective determination of the color, increase was observed (P ≤ 0.05) in the L* values (57.77 to 59.2), whereas the b* values were found to reduce (14.9 to 13.3), and no influence (P > 0.05) of sodium nitrite was observed for any of the color parameters assessed. Although the pH and acidity values had no significant differences at the different concentrations of nitrite, they did show variation (P ≤ 0.05) during the storage period, specifically 5.78 to 5.66 and 7.95 to 9.75% lactic acid, respectively. The residual nitrite contents increased (P ≤ 0.05) from 1.95 to 6.57 mg.kg-1 on the 1st day, when the nitrite concentration rose from 50 to 200 mg.kg-1, but during the conditioning time, it reduced almost completely, presenting levels below 2 mg.kg-1 on the 15th day. In the microbiological evaluation of the fresh pork sausage, counts lower than 1 × 103 NMP.g-1 were observed for total and thermo-tolerant coliforms; for coagulase-positive Staphylococcus all the results were negative, showing it to be in accordance with the Brazilian legislation. At the count of psychrotrophic microorganisms, all treatments presented counts above 6 Log cfu.g-1. Given the aforementioned results, we conclude that all treatments showed to be stable at lipid peroxidation and microbiological evaluation. Thus, it may be possible to reduce the sodium nitrite concentrations used in the preparation of fresh pork sausage. However, before adopting this measure, more studies should be conducted to evaluate the influence of nitrite concentrations on the other variables associated with preservation and safety of fresh pork sausage / Durante o processamento de produtos cárneos curados são utilizados alguns conservantes químicos como o nitrito de sódio, com o objetivo de conservar, alterar características sensoriais e diversificar a produção. A adição de nitrito tem sido associada a uma imagem negativa em relação a saúde dos consumidores devido a formação de nitrosaminas, o que tem levado a indústria de alimentos a reconsiderar a quantidade de nitrito utilizada. Considerando essa abordagem, o objetivo deste trabalho consistiu em avaliar a influência da concentração do nitrito de sódio na estabilidade oxidativa e na contagem microbiológica da linguiça suína frescal. Foram elaborados amostras de linguiça com 0, 50, 100, 150 e 200 mg.kg-1 de nitrito de sódio, que foram embaladas a vácuo e armazenadas a temperatura de 5ºC. Foram avaliados o perfil de oxidação lipídica, por meio do número de substâncias reativas ao ácido tiobarbitúrico (TBARS), a cor, o pH, a acidez e a quantificação de nitrito residual ao longo do período de armazenamento (Dias 1, 8 e 15). A avaliação microbiológica foi feita por meio de contagens de coliformes totais (NMP.g-1); coliformes termotolerantes (NMP.g-1), microrganismos psicrotróficos (Log.UFC.g-1) e Staphylococcus coagulase positiva (UFC.g-1) nos dias 0, 7 e 14. Durante o período estudado, observou-se número de TBARS de 0,24 mg.kg-1, quando adicionou-se 50 mg.kg-1 de nitrito e 0,09 mg.kg-1, quando utilizou-se 200 mg.kg-1, verificando-se uma redução (P ≤ 0,05) no número de TBARS com o aumento da concentração de nitrito de sódio. Durante o tempo de armazenamento foi observado um aumento (P ≤ 0,05) nos valores de TBARS, de 0,14 mg.kg-1 para 0,21 mg.kg-1, evidenciando que houve desenvolvimento do processo de oxidação lipídica. Com relação à determinação objetiva da cor, foi observado durante o tempo avaliado, aumento (P ≤ 0,05) dos valores de L* de 57,77 para 59,2, e redução (P ≤ 0,05) dos valores de b* de 14,9 para 13,3, não sendo observada influência (P > 0,05) do nitrito de sódio em nenhum dos parâmetros de cor avaliados. Embora os valores de pH e acidez não tenham tido diferenças significativas nas distintas concentrações de nitrito, apresentaram variação (P ≤ 0,05) durante o período de armazenamento, verificando valores de 5,78 para 5,66 e 7,95 para 9,75 % de ácido lático, respectivamente. Os teores de nitrito residual aumentaram (P ≤ 0,05) de 1,95 para 6,57 mg.kg-1 no 1º dia, quando a concentração de nitrito se elevou de 50 para 200 mg.kg-1, mas durante o tempo de acondicionamento, reduziu-se quase que completamente, apresentando níveis menores que 2 mg.kg-1 no 15º dia. Durante a avaliação microbiológica da linguiça suína frescal, observou-se contagens para coliformes totais e termotolerantes inferiores a 1 x 103 NMP.g-1 e para Staphylococcus coagulase positiva, todos os resultados foram negativos, mostrando-se em acordo com a legislação brasileira. Na contagem de microrganismos psicrotróficos, todos os tratamentos apresentaram contagens superiores a 6 Log UFC.g-1. Diante dos resultados apresentados, conclui-se que todos os tratamentos apresentaram-se estáveis à oxidação lipídica e à avaliação microbiológica. Assim, poderia ser possível reduzir as concentrações de nitrito de sódio usadas no preparo da linguiça suína frescal. Porém, antes de adotar esta medida, são necessários mais estudos para avaliar a influência das concentrações de nitrito sobre outras variáveis associadas à conservação e segurança da linguiça suína frescal
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Reduction of Sodium Nitrite and Sodium Chloride in a Cured Meat Product by Using Acid Development to Inhibit Botulinal Toxin FormationAssamongkorn, Angsana 01 May 1985 (has links)
Pediococcus acidilactici as a lactic acid producer, and sucrose were added to breakfast strip products in order to reduce added levels of sodium nitrite and sodium chloride and yet limit the growth of Clostridium botulinum and inhibit toxin production. Sucrose at 0.4 or 0.9% with P. acidilactici at 1.0 x 10 cells/g were added during preparation of breakfast strip products prepared with combinations of 40 or 80 ppm sodium nitrite and 1.0 or 2.0% sodium chloride. Other ingredients were added at levels normally used in cured meat products. C. botulinum types A and B at 1,000 spores/g were inoculated during product preparation. The finished products were sliced, vacuum packed, double bagged, vacuum sealed again, and incubated at 27 C. Samples were analyzed before incubation and every week for 4 weeks for anaerobic plate counts, pH, residual nitrite, Most Probable Number counts, and botulinal toxin. The results revealed that 0.9% sucrose increased the acid production, thus inhibiting the botulinal growth and toxin formation in the products. Lactic acid bacteria and sucrose at 0.4% did not produce enough acid to inhibit toxin formation. Sodium nitrite at 40 ppm and sodium chloride at 1.0% permitted increased growth rate and toxin development of C. botulinum. Addition of 0.9% sucrose and P. acidilactici was necessary to provide antibotulinal properties to breakfast strip products prepared with 40 ppm sodium nitrite and 1.0% sodium chloride.
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AVALIAÇÃO DA UTILIZAÇÃO DE ADITIVOS DE BENZOATO E NITRITO DE SÓDIO NA PROTEÇÃO DA CORROSÃO DO AÇO 1006Silva, Suélen Crevelim da 20 December 2013 (has links)
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Previous issue date: 2013-12-20 / Every year, corrosion in metallic substrates causes waste in the order of millions of dollars, and with the prohibition or restriction in the use of substances such as chromium there is a need for alternatives to increase the life cycle of metallic apparatuses. This work incorporated sodium benzoate and sodium nitrite as corrosion inhibitor in commercial paints, which assists in the prevention against
environment corrosion. Synthetic enamel paint from Coral was used as a vehicle for the addition of the inhibitors; the paints were applied on working electrodes made of
SAE 1006 steel that is a low carbon and easily corroded steel. Afterwards, potentionstat measurements were performed according to the ASTM standard G59-97(2009). Satisfactory results were found when sodium nitrite was use in the concentration of 0.05% and 0.7%, showing corrosions rates of 8,8602.10-05 mm/year and 2,2207.10-04 mm/year, respectively; samples containing 0.5% of sodium benzoate showed a corrosion rate of 1,3994.10-4 mm/year. These corrosion rates prove the efficiency of using corrosion inhibitors because the SAE 1006 steel presented a corrosion rate of 2,1759 mm/year. Coatings were also characterized by using scanning electron microscopy, and IR spectroscopy.
Keywords: Sodium nitrite; sodium benzoate; potentiostat; anticorrosive; SAE 1006
steel. / A corrosão em substratos metálicos é a causa de gastos na escala de milhões de dólares, todos os anos e com a proibição ou restrição do uso de substâncias como o
cromo, por exemplo, buscam-se alternativas para aumentar a vida útil de aparatos metálicos. Este trabalho procurou incorporar benzoato de sódio e nitrito de sódio
como aditivos inibidores de corrosão em tintas comerciais, que auxiliam no aumento da proteção contra a corrosão ambiente. Como meio para a adição foi usado um
esmalte sintético da Coral, aplicado sobre eletrodos de trabalho feitos com aço SAE 1006 que tem teor de carbono baixo e é fácil de ser corroído. Em seguida foram
realizadas medidas potenciométricas seguindo a norma ASTM G59-97(2009). Os resultados obtidos foram satisfatórios com o uso de nitrito de sódio nas concentrações de 0,05 % e 0,7 % apresentando taxas de corrosão em torno de 8,8602.10-05 mm/a e 2,2207.10-04 mm/a respectivamente e para o benzoato de sódio
na concentração de 0,5 % com taxa de corrosão em torno de 1,3994.10-4 mm/a, comprovando a eficiência do uso de inibidores uma vez que o aço 1006 possui taxa
de corrosão em 2,1759 mm/a. Os filmes de melhor resultado também foi caracterizados por técnicas de microscopia eletrônica de varredura e o que mais se
destacou também foi caracterizado por espectroscopia na região do Infravermelho.
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