• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 9
  • 1
  • 1
  • 1
  • Tagged with
  • 13
  • 13
  • 6
  • 6
  • 5
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 3
  • 3
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Potassium sorbate as a fungistatic agent in country ham processing

Frank, Philip Randall January 1977 (has links)
A study was conducted to determine the feasibility of utilizing potassium sorbate as a fungistatlc agent in country ham processing. The study was divided into three phases: the first utilized 60 and 90 day old cured country (long cut) ham; the second used country ham slices; and the third phase utilized 70 day old country cured (packer style cut) hams. Samples were incubated at various temperatures and relative humidities to determine the extent of protection offered by sorbate against fungal growth. Intensity of fungal growth was determined subjectively through periodic visible evaluations and were quantitated by culture plating methods. A UV spectrophotometric technique was utilized to determine the concentrations of sorbic acid deposited on ham surfaces or slices by various methods of application. Of the different methods of application that were tested, the 5% (W/V) 1 minute spray offered the lowest effective level for inhibition of fungal growth. The 5% l minute spray significantly lowered initial mold and yeast colony counts and protected the hams for 30 to 60 days under conditions conducive to fungal outgrowth (21.1±5°C and 70±5% relative humidity). An analogous 10% spray provided a slightly greater measure of mold inhibition than the 5% treatment under identical conditions. / Master of Science
2

Avaliação do uso de conservantes sobre a estabilidade microbiologica de agua de coco carbonatada / Evaluation of the use of preservatives on the microbiological stability of carbonated coconut water

Pereira, Eliene Penha Rodrigues 04 September 2010 (has links)
Orientador: Jose de Assis Fonseca Faria / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-15T10:39:30Z (GMT). No. of bitstreams: 1 Pereira_ElienePenhaRodrigues_M.pdf: 2626940 bytes, checksum: 872960c1af9cf987688832b45e82d078 (MD5) Previous issue date: 2010 / Mestrado / Mestre em Tecnologia de Alimentos
3

Desenvolvimento e caracterização de biofilmes ativos a base de polimeros de fontes renovaveis e sua aplicação no acondicionamento de pães de forma / Development and characterization of active biofilms based on polymer from renewed sources and their application to preserve pan breads

Bertan, Larissa Canhadas 25 November 2008 (has links)
Orientador: Fernanda Paula Collares Queiroz, Theo Guenter Kieckbusch / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-11T22:22:43Z (GMT). No. of bitstreams: 1 Bertan_LarissaCanhadas_D.pdf: 3212873 bytes, checksum: fe398494b5ab4899a63848bef01c100a (MD5) Previous issue date: 2008 / Resumo: Pesquisas sobre biofilmes à base de polímeros surgiram devido ao impacto ambiental aliado à necessidade de reduzir os resíduos sólidos. Atualmente, vários estudos estão voltados ao desenvolvimento de tecnologia que controle o crescimento indesejável de microorganismos, através de embalagens ativas. O objetivo deste trabalho foi obter as melhores formulações para o desenvolvimento de biofilmes ativos e avaliar sua aplicação no acondicionamento de pães de forma. Filmes simples e compostos à base de gelatina, glúten e amido (mandioca, mandioca modificado, milho ceroso e milho ceroso modificado) foram desenvolvidos e caracterizados quanto à permeabilidade ao vapor de água (PVA), permeabilidade ao oxigênio (PO2), solubilidade em água (SOL) e propriedades mecânicas (resistência à tração - RT e porcentagem de elongação - ELO), variando a concentração da macromolécula e do plastificante (glicerol). Os filmes contendo 10 g de gelatina com 5% de glicerol (em relação à massa seca da proteína) e o filme com 5 g de glúten, 32,5 mL de etanol/100 mL de solução, pH 5 e 20% de glicerol (em relação à massa seca da proteína) foram selecionados para a elaboração dos filmes compostos. Filmes compostos de glúten/gelatina (GLU/GEL), amido de mandioca/gelatina (AM/GEL), amido de mandioca modificado/gelatina (AMM/GEL), amido de milho ceroso/gelatina (AMC/GEL), amido de milho ceroso modificado/gelatina (AMCM/GEL) em diversas proporções 1:1, 1:4 e 4:1 e amido/gelatina/glúten (AM/GLU/GEL; AMM/GLU/GEL, AMC/GLU/GEL e AMCM/GEL) na proporção 1:1:1, também foram confeccionados e caracterizados. Os filmes compostos apresentaram menor PVA e maior RT que os filmes simples de gelatina. Os filmes compostos AMM/GEL, GLU/GEL e AMM/GLU/GEL, nas proporções 4:1; 4:1 e 1:1:1, respectivamente, foram utilizados no desenvolvimento de filmes ativos. Os filmes compostos foram adicionados de sorbato de potássio (SP) na concentração de 2 e 4% (p/v). A adição de SP provocou aumento na PVA, na SOL e na ELO e redução na RT, em relação aos filmes sem sorbato. A superfície dos filmes compostos mostrou-se lisa e homogênea, com exceção do filme AMM/GLU/GEL com 4% de SP. Para os testes de difusão em halo, foram isolados 5 fungos: (i) Eurotium chevalieri; (ii) Eurotium amstelodami; (iii) Wallemia sebii; (iv) Penicillium raistrickii e (v) Cladosporium sp. Os filmes que apresentaram maior eficiência na redução do crescimento dos fungos e melhores propriedades de barreira e mecânicas foram: (i) AMM/GEL e (ii) GLU/GEL, ambos com 2% de SP. Os filmes ativos selecionados no teste de difusão em halo apresentaram duas tangentes de perda (tan ?), indicando a existência de duas Tg. Os filmes de GLU/GEL, sem e com 2% SP, foram utilizados no acondicionamento de pão de forma, sendo que as fatias de pães justapostas foram intercaladas com os filmes ativos e colocadas em sacos de polietileno de baixa densidade. O uso de filmes entre as fatias provocou aumento da firmeza, diminuição da umidade e da atividade de água. A análise microbiológica não indicou diferença significativa entre a estocagem com filmes ativos e o controle. No 7° dia, os pães continham a quantidade máxima de SP permitida no produto pela legislação brasileira / Abstract: In recent years the research on polymer-based biofilms has seen considerable increase due to concern over environmental impact and the need to reduce solid residue generation. There are several studies concerning the control of microbial activity in prepared food using active packaging. The objective of this work was to develop the best formulation of active biofilms and to evaluate their performance in sliced bread packaging. Simple and composite films were developed, based on gelatin, gluten and diferent types of starch (cassava, modified cassava, waxy maize and modified waxy maize starches). Films were characterized for their permeability to water vapor (WVP), permeability to oxygen (PO2), solubility in water (SOL) and mechanical properties (tensile strengh -TS and elongation -ELO), using different concentrations of the macromolecules and plasticizer (glycerol). Films containing 10g of gelatin and 5% of glycerol (based on protein dry mass) and films with 5g of gluten, 32.5 mL of ethanol/mL of solution, at pH of 5 and 20% glycerol (based on protein dry mass) were selected for the manufacture of composite films. Composite films of gluten/gelatin (GLU/GEL), cassava starch/gelatin (CS/GEL), modified cassava starch/gelatin (MCS/GEL), waxy maize starch/gelatin (WMS/GEL), modified waxy maize starch/gelatin (MWMS/GEL), at 1:1, 1:4 and 4:1 ratios and starch/gelatin/gluten (S/GLU/GEL) at 1:1:1 ratio were manufactured and characterized. Composite films presented lower WVP and larger RT than simple gelatin film. Composite films based on MCS/GEL, GLU/GEL and MCS/GLU/GEL at 4:1, 4:1 and 1:1:1 ratios, respectively, were used for the development of active films usine, potassium sorbate (PS) at 2 and 4%, in volume concentrations. Addition of PS promoted increase in WVP, SOL and ELO as well as a decrease in TS, when compared to films with no added anti-microbial agent. Surface of the composite films were smooth and homogeneous except for the MCS/GLU/GEL with 4% PS. Five microorganisms were selected, for the diffusion halo assay: (i) Eurotium chevalieri; (ii) Eurotium amstelodami; (iii) Wallemia sebii; (iv) Penicillium raIstrickiI e (v) Cladosporium sp. Films that presented the best efficiency on reduction of microbial growth as well as best permeability and mechanical properties were: (i) MCS/GEL and (ii) GLU/GEL, both with 2% of added PS. The active films selected for the diffusion halo assay presented two loss tangent (tan?) values, an indication of two Tgs. GLU/GEL films, with no sorbate and with 2% sorbate, were used in sliced bread packaging. Each slice was placed between two sheets of active film and the whole bread was stored inside a low density polyethylene bag. The active films promoted an increase in firmness and a decrease in both moisture content and water activity of the slices. The microbial analysis, storage with active films showed no significant difference from the control sample. By the seventh day of storage the accumulated amout of, potassium sorbate liberated by the film achieved the limit set by Brazilian legislation / Doutorado / Doutor em Tecnologia de Alimentos
4

Efficacy of Ultraviolet Light in Combination with Chemical Preservatives for the Reduction of Escherichia coli in Apple Cider

Quicho, Joemel Mariano 15 July 2005 (has links)
Hazard Analysis Critical Control Point (HACCP) regulations for juice manufacture require the application of a process that will result in a 5-log reduction (99.999%) of the pertinent pathogen in the juice being processed. The use of ultraviolet (UV) light, as an alternative to traditional thermal processing, has been adopted by some juice processors as a means of meeting the HACCP 5-log performance standard. However, little research had been performed to determine the effect of UV when used in combination with antimicrobial agents that are commonly added to juice products. Therefore, the objectives of this work were (1) to determine if chemical preservatives and ultraviolet light have a combined effect on the reduction of Escherichia coli in apple cider, and (2) to determine the influence of adding chemical preservatives at different points in the processing of juice (i.e., either prior to or after ultraviolet light processing) on the reduction of Escherichia coli in apple cider. In this study, refrigerated (4°C) pasteurized apple cider that contained no added preservatives was inoculated with E. coli ATCC 25922, a surrogate strain for E. coli O157:H7, and exposed to UV (peak output: 254 nm). The following chemical preservatives were added to apple cider either prior to or after UV exposure: dimethyl dicarbonate (75 and 150 ppm), hydrogen peroxide (75 and 150 ppm), potassium sorbate (1000 and 2000 ppm), and sodium benzoate (1000 and 2000 ppm). Following UV exposure and chemical preservative application, inoculated juices were stored at 4°C for 72 hours. Samples were collected prior to and immediately after UV exposure and at 24, 48, and 72 hours of storage. At each sampling point, juice portions (0.1 ml) were serially diluted in peptone diluent (0.1%) and surface plated onto Tryptic Soy Agar (TSA). Counts of the bacterial colonies were made 48 hours after incubating plates at 35°C. Overall, reductions of E. coli were greater in cider treated with preservatives after UV processing than when preservatives were added prior to UV processing (P < 0.05). Furthermore, dimethyl dicarbonate and hydrogen peroxide were more effective than potassium sorbate and sodium benzoate in reducing E. coli populations in conjunction with UV (P < 0.05). When added prior to UV exposure, potassium sorbate was the least effective, allowing for the greatest survival (P < 0.05). This study describes the use of UV in conjunction with hydrogen peroxide and dimethyl dicarbonate as an effective method for producing a 5-log or greater reduction of E. coli O157:H7 in apple cider. / Master of Science
5

Metodutveckling för optimering av kaliumsorbat i mättad saltlake : För inhibition av jäst

Thörngren, Elias January 2024 (has links)
Humans have been using milk from cattle for at least 10 000 years. During millennia, techniques for the refinery of milk to cheese have evolved resulting in the transition from small scale local production to the industrialized manufacture seen today. A problem faced today is the occurrence of dairy spoilage yeasts, of whom species belonging to the genus Candida is most prevalent. Methods to combat spoilage fungi involves the use of chemical preservatives, of which salts of sorbic acid are widely used. In water, the sorbate ion accepts a proton from the oxonium ion resulting in the formation of sorbic acid. Sorbic acid can diffuse into and over cellular membranes of yeasts, where it disrupts a range of functions. The most important being the disruption of proteins located in the mitochondrial membranes, resulting in an inhibition of the respiratory chain. The process of salting cheese is usually done by submersion in brine. The brine used is home to a diverse microflora, sometimes comprising said yeasts. The purpose of this work was to develop a method to investigate whether a reduced use of potassium sorbate in brine is possible. Two methods were developed, one where yeast was inoculated into different concentrations of potassium sorbate. The other used yeast in suspension derived from a simulated brining tank. The results showed that the simulated brining tank worked better, and a potential reduction to 1/3 of the current use of sorbate is possible. However, the experimental basis for this conclusion, even though supported by previous studies, is weak.
6

Efeito de diferentes concentrações de conservantes alimentícios no crescimento in vitro de fungos termorresistentes e bactérias patogênicas. / Effect of different concentrations of food preservatives on the growth of heat-resistant and pathogenic bacteria in vitro.

Lima-coelho, Sheyla Ferreira 22 January 2008 (has links)
The foods are excellent nutrient sources for a wide variety of microorganisms, such as filamentous fungi and yeast or bacteria. They are therefore vehicle for a number of infectious diseases. So the man has sought to prevent such proliferation microbial, and maintain the integrity of the product to be sold or consumed, through physical and chemical barriers. To reduce the risk of multiplication of microorganisms and the consequent deterioration of food, the industries are using, in addition to heat treatment, increasingly, chemical additives (preservatives). Among them, sulphur dioxide, sorbic acid and benzoic acid, and derivatives of them, have been employed in the steps of processing. Thus, seeking to provide subsidies to reduce the use of inadequate quantities of preservatives in the food industry, and therefore unfit to ingestion by the population, it was determined in this work the minimum concentrations of sodium metabisulphite, sodium benzoate and sorbate, potassium necessary for the inhibition of the development of heat-resistant fungi, such as Byssochlamys fulva, Neosartorya fischeri and Talaromyces flavus, and of bacteria, such as Salmonella Enteritidis, S. Typhimurium, Escherichia coli and Bacillus cereus in vitro. The growth-media used were Potato-Dextrose-Agar (PDA) and Tripton- Soybean-Agar (acidified with citric acid, pH 3.5 and 5), for tests with fungi and bacteria, respectively. To these media were added the preservatives in different quantities, in order to obtain concentrations of 100, 150, 200, 250, 300, 400, 500, 600, 700, 800 and 1000 mg.L-1 of them. After inoculation and incubation (28 and 30 ± 2 ° C, in the dark), it was observed that the lowest concentrations of sodium metabisulphite showed greater efficiency in inhibiting the growth of all microorganisms, in comparison with the other preservatives tested in vitro. The lowest concentrations of sodium benzoate, on the other hand, were more effective in inhibiting bacterial growth. Already the potassium sorbate showed greater action to combat the heat-resistant fungi. / Fundação de Amparo a Pesquisa do Estado de Alagoas / Os alimentos se constituem em ótimos suprimentos para uma grande diversidade de microrganismos, sendo eles fungos filamentosos e leveduriformes ou bactérias. São, portanto, veículo de uma série de doenças infecciosas. Assim o homem tem buscado evitar tal proliferação microbiana, mantendo a integridade do produto a ser comercializado ou consumido, através de barreiras físicas e químicas. Para reduzir os riscos de multiplicação de microrganismos e a conseqüente deterioração dos alimentos, as indústrias estão utilizando, além do tratamento térmico, cada vez mais, aditivos químicos (conservantes). Entre eles, o dióxido de enxofre, ácido benzóico e o ácido sórbico, além de derivados dos mesmos, têm sido empregados em linhas de processamento. Assim, visando fornecer subsídios para se reduzir a utilização de quantidades inadequadas de conservantes pela indústria de alimentos e, portanto, a ingestão imprópria dos mesmos pela população, determinou-se neste trabalho as concentrações mínimas de metabissulfito de sódio, benzoato de sódio e sorbato de potássio necessárias à inibição do desenvolvimento dos fungos termorresistentes Byssochlamys fulva, Neosartorya fischeri e Talaromyces flavus, e das bactérias Salmonella Enteritidis, S. Typhimurium, Escherichia coli e Bacillus cereus in vitro. Os meios de cultura utilizados foram Batata-Dextrose- Agar (BDA) e Triptona-Soja-Agar (acidificado com ácido cítrico, pH 3,5 e 5), respectivamente para os ensaios com fungos e com bactérias. A esses meios adicionaram-se os conservantes em diferentes quantidades, de modo a obterem-se concentrações compreendidas entre 80 e 1000 mg.L-1 dos mesmos. Após inoculação e incubação (28 e 30 ± 2 ºC, no escuro), observou-se que as menores concentrações do metabissulfito de sódio apresentaram uma maior eficiência em inibir o crescimento de todos os microrganismos em comparação com os demais conservantes testados in vitro. As menores concentrações do benzoato de sódio, por outro lado, foram mais efetivas em inibir o crescimento bacteriano. Já o sorbato de potássio apresentou maior ação no combate aos fungos termorresistentes.
7

Qualidade microbiológica e ocorrência de leveduras em bebidas lácteas fermentadas, com adição de polpas de frutas, comercializada na região de São José do Rio Preto - SP

Reis, Janaína Alves dos [UNESP] 25 February 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-02-25Bitstream added on 2014-06-13T19:50:09Z : No. of bitstreams: 1 reis_ja_me_sjrp.pdf: 321072 bytes, checksum: a97e35a10a1ed607424c4a24026412f3 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Este estudo foi desenvolvido com o intuito de avaliar a qualidade microbiológica de bebidas lácteas fermentadas, com adição de polpas de frutas, comercializadas na região de São José do Rio Preto, SP, por meio das seguintes análises: contagem de bactérias aeróbias mesófilas, enumeração de bolores e leveduras, determinação do Número Mais Provável (NMP) de coliformes e coliformes termotolerantes, pesquisa de Escherichia coli e Salmonella spp., sendo realizado ainda a determinação do pH eletrométrico. Dos resultados, observou-se que das 31 amostras (100,00%) analisadas, 5 (16,13%) foram classificadas como “produtos em condições sanitárias insatisfatórias” e, portanto, “produtos impróprios para consumo humano”, por apresentarem coliformes termotolerantes acima do padrão estabelecido pela legislação vigente. Destas amostras, foram ainda isoladas 74 leveduras (100,00%), que foram submetidas às provas taxonômicas, morfológicas, fisiológicas e de assimilação de várias fontes de carbono. De acordo com as provas taxonômicas, verificou-se que esses microrganismos pertenciam as seguintes espécies: Cryptococcus albidus (1,35%), Cryptococcus laurentii (1,35%), Candida edax (1,35%) e Debaryomyces hansenii var. fabryii (95,95%). Foi verificada também a resistência dessas leveduras em relação aos principais conservantes alimentícios contidos na legislação brasileira, como benzoato de sódio (INS - 211) nas concentrações de 0,10; 0,20 e 0,40% e sorbato de potássio (INS - 202) nas de 0,015; 0,03; 0,05; 0,06; 0,10; 0,20 e 0,40%. As concentrações de 0,20% de benzoato de sódio e 0,40% de sorbato de potássio foram as mais eficazes, representando respectivamente, 50,67 e 81,33% das culturas sensíveis à presença dos conservantes testados. Recomenda-se, portanto como... / This study was objective in order to evaluate the microbiological quality of fermented dairy beverages, with the addition of fruit pulps, commercialized in the region of São José do Rio Preto, SP, through the following analyses: mesophilic aerobic bacteria count, enumeration of moulds and yeasts, determination of the Most Probable Number (MPN) of total and thermotolerants coliforms, Escherichia coli and Salmonella spp research, being the determination of pH still carried on. The results pointed out that 5 (16.13%) out of 31 (100.00%) analyzed samples were classified as “products in unsatisfactory sanitary conditions”, therefore “inappropriate products for human consumption”, because they present thermotolerants coliforms above the standard established by the current legislation. Seventy-four (74) yeasts were isolated from the samples (100.00%), which were submitted to taxonomic, morphological and physiological tests, and to carbon source assimilation tests, as well. According to the taxonomic tests, those microorganisms belonged to the following species: Cryptococcus albidus (1.35%), Cryptococcus laurentii (1.35%), Candida edax (1.35%) e Debaryomyces hansenii var. fabryii (95.95%). The resistance of these yeasts in relation to the main food preservatives present in Brazilian legislation, such as benzoate sodium (INS - 211) at concentrations of 0.10; 0.20 and 0.40% and potassium sorbate (INS - 202) at 0.015; 0.03; 0.05; 0.06; 0.10; 0.20 and 0.40%; was also reported. The concentrations of benzoate sodium at 0.20% and potassium sorbate at 0.40% were the most effective, representing 50.67% and 81.33%, of the sensitive cultures to the presence of the preservatives tested. So, based on the results, the current monitoring of the different phases involved in the manufacturing xix process of these products is fundamental, in order to assure the capacity to their useful life as well as to minimize the damage to the consumer’s health.
8

Verificação das boas práticas de fabricação (BFP) e análise da qualidade microbiológica de saladas adicionada de maionese comercializadas na cidade de São José do Rio Preto - SP

Seixas, Fernanda Rosan Fortunato [UNESP] 18 February 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-02-18Bitstream added on 2014-06-13T20:10:50Z : No. of bitstreams: 1 seixas_frf_me_sjrp.pdf: 308372 bytes, checksum: 79dc807bb402317ba0cb325f7c61e4fa (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / No Brasil, estima-se que, de cada cinco refeições, uma não é efetuada em casa, sendo a salada de maionese um dos alimentos comumente consumidos. Este produto alimentício é basicamente constituído por vegetais cozidos posteriormente adicionados de maionese. Portanto, além da microbiota presente nos vegetais, a falta de higiene dos manipuladores durante o seu preparo, bem como as condições de armazenamento do produto, faz com que os microrganismos possam vir a ocasionar deteriorações no alimento ou intoxicações alimentares nos consumidores. Neste trabalho as Boas Práticas de Fabricação (BPF) foram verificadas em 10 estabelecimentos produtores de saladas de maionese aplicando um check - list que se constituiu de 123 itens de verificação baseado na legislação vigente no país (Resolução da Diretoria Colegiada - RDC nº. 216 de 2004) e análise da qualidade microbiológica perante 57 amostras destas saladas comercializadas na cidade de São José do Rio Preto - SP. As análises microbiológicas foram realizadas em 2 etapas: a primeira em 30 amostras no período de junho, agosto e outubro de 2006, e a segunda etapa no período de fevereiro, abril e junho de 2007, após a aplicação do check - list e orientações para o correto manuseio desse alimento. Foram realizadas as seguintes análises: contagem de bolores e leveduras, Staphylococcus aureus, Número Mais Provável (NMP) de coliformes totais, termotolerantes, pesquisa de Escherichia coli e de Salmonella spp., bem como procedeu-se a identificação das leveduras isoladas e o teste de resistência frente a diferentes concentrações do conservante sorbato de potássio. De acordo com o check - list aplicado para verificação das BPF, 70,0% dos estabelecimentos apresentaram não conformidades superiores a 25,0%, sendo classificados como insatisfatórios para produção de alimentos... / The aim of this work was to verify the Good Manufacturing Practices (GMP) and the microbiologic quality of the salads added of mayonnaise marketed in São José do Rio Preto - SP, through the following analyses: check - list application, based on the legislation in force in the country, which classified the levels of suitability presented by the producers, counting of mould and yeast, Staphylococcus aureus, determining the Most Probable Number of total and heat resistant coliforms, Escherichia coli and Salmonella spp research, and proceeded to identification isolated yeast and resistance test to different concentrations of potassium sorbate conserver. According to the check - list applied to GMP verification, 70,0% of the establishments showed no conformities above 25,0%, being classified as unsatisfactory for food production. The obtained result for mould and yeast counting varied from 1,9 x 103 to 6,0 x 106.. The biggest number of mayonnaise salad contamination was caused by Staphylococcus aureus with variations of < 100 a 1,8 x 107 UFC/g. For The Most Probable Number determination of total and heat resistant coliforms a variation of < 3 a > 1100 NMP/g was verified. Escherichia coli was found in all samples positive for heat resistantt coliforms. Salmonella spp. was not found. From the ten establishments 4 (40%) improved the salads quality with mayonnaise added and 1 (10%) stopped this food production after inspection and the technicians of Sanitary Survellance guidance. In relation to the isolated yeasts, Debaryomyces hansenii var. fabryii species was the most frequent, in 19 cultures (76,0%) followed by Cryptococcus laurentii with 4 (16%), Arxula adeninovorans with 1 (4,0%). The species Arxula adeninovorans and Candida edax were not sensitive to potassium sorbate conserver. In relation to...(Complete abstract click electronic access below)
9

Qualidade microbiológica e ocorrência de leveduras em bebidas lácteas fermentadas, com adição de polpas de frutas, comercializada na região de São José do Rio Preto - SP /

Reis, Janaína Alves dos. January 2008 (has links)
Orientador: Fernando Leite Hoffmann / Banca: Alexandre Rodrigo Coelho / Banca: Ana Lúcia Barretto Penna / Resumo: Este estudo foi desenvolvido com o intuito de avaliar a qualidade microbiológica de bebidas lácteas fermentadas, com adição de polpas de frutas, comercializadas na região de São José do Rio Preto, SP, por meio das seguintes análises: contagem de bactérias aeróbias mesófilas, enumeração de bolores e leveduras, determinação do Número Mais Provável (NMP) de coliformes e coliformes termotolerantes, pesquisa de Escherichia coli e Salmonella spp., sendo realizado ainda a determinação do pH eletrométrico. Dos resultados, observou-se que das 31 amostras (100,00%) analisadas, 5 (16,13%) foram classificadas como "produtos em condições sanitárias insatisfatórias" e, portanto, "produtos impróprios para consumo humano", por apresentarem coliformes termotolerantes acima do padrão estabelecido pela legislação vigente. Destas amostras, foram ainda isoladas 74 leveduras (100,00%), que foram submetidas às provas taxonômicas, morfológicas, fisiológicas e de assimilação de várias fontes de carbono. De acordo com as provas taxonômicas, verificou-se que esses microrganismos pertenciam as seguintes espécies: Cryptococcus albidus (1,35%), Cryptococcus laurentii (1,35%), Candida edax (1,35%) e Debaryomyces hansenii var. fabryii (95,95%). Foi verificada também a resistência dessas leveduras em relação aos principais conservantes alimentícios contidos na legislação brasileira, como benzoato de sódio (INS - 211) nas concentrações de 0,10; 0,20 e 0,40% e sorbato de potássio (INS - 202) nas de 0,015; 0,03; 0,05; 0,06; 0,10; 0,20 e 0,40%. As concentrações de 0,20% de benzoato de sódio e 0,40% de sorbato de potássio foram as mais eficazes, representando respectivamente, 50,67 e 81,33% das culturas sensíveis à presença dos conservantes testados. Recomenda-se, portanto como...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study was objective in order to evaluate the microbiological quality of fermented dairy beverages, with the addition of fruit pulps, commercialized in the region of São José do Rio Preto, SP, through the following analyses: mesophilic aerobic bacteria count, enumeration of moulds and yeasts, determination of the Most Probable Number (MPN) of total and thermotolerants coliforms, Escherichia coli and Salmonella spp research, being the determination of pH still carried on. The results pointed out that 5 (16.13%) out of 31 (100.00%) analyzed samples were classified as "products in unsatisfactory sanitary conditions", therefore "inappropriate products for human consumption", because they present thermotolerants coliforms above the standard established by the current legislation. Seventy-four (74) yeasts were isolated from the samples (100.00%), which were submitted to taxonomic, morphological and physiological tests, and to carbon source assimilation tests, as well. According to the taxonomic tests, those microorganisms belonged to the following species: Cryptococcus albidus (1.35%), Cryptococcus laurentii (1.35%), Candida edax (1.35%) e Debaryomyces hansenii var. fabryii (95.95%). The resistance of these yeasts in relation to the main food preservatives present in Brazilian legislation, such as benzoate sodium (INS - 211) at concentrations of 0.10; 0.20 and 0.40% and potassium sorbate (INS - 202) at 0.015; 0.03; 0.05; 0.06; 0.10; 0.20 and 0.40%; was also reported. The concentrations of benzoate sodium at 0.20% and potassium sorbate at 0.40% were the most effective, representing 50.67% and 81.33%, of the sensitive cultures to the presence of the preservatives tested. So, based on the results, the current monitoring of the different phases involved in the manufacturing xix process of these products is fundamental, in order to assure the capacity to their useful life as well as to minimize the damage to the consumer's health. / Mestre
10

Verificação das boas práticas de fabricação (BFP) e análise da qualidade microbiológica de saladas adicionada de maionese comercializadas na cidade de São José do Rio Preto - SP /

Seixas, Fernanda Rosan Fortunato. January 2008 (has links)
Orientador: Fernando Leite Hoffmann / Banca: Elisa Yoko Hirooka / Banca: Crispin Humberto Garcia Cruz / Resumo: No Brasil, estima-se que, de cada cinco refeições, uma não é efetuada em casa, sendo a salada de maionese um dos alimentos comumente consumidos. Este produto alimentício é basicamente constituído por vegetais cozidos posteriormente adicionados de maionese. Portanto, além da microbiota presente nos vegetais, a falta de higiene dos manipuladores durante o seu preparo, bem como as condições de armazenamento do produto, faz com que os microrganismos possam vir a ocasionar deteriorações no alimento ou intoxicações alimentares nos consumidores. Neste trabalho as Boas Práticas de Fabricação (BPF) foram verificadas em 10 estabelecimentos produtores de saladas de maionese aplicando um check - list que se constituiu de 123 itens de verificação baseado na legislação vigente no país (Resolução da Diretoria Colegiada - RDC nº. 216 de 2004) e análise da qualidade microbiológica perante 57 amostras destas saladas comercializadas na cidade de São José do Rio Preto - SP. As análises microbiológicas foram realizadas em 2 etapas: a primeira em 30 amostras no período de junho, agosto e outubro de 2006, e a segunda etapa no período de fevereiro, abril e junho de 2007, após a aplicação do check - list e orientações para o correto manuseio desse alimento. Foram realizadas as seguintes análises: contagem de bolores e leveduras, Staphylococcus aureus, Número Mais Provável (NMP) de coliformes totais, termotolerantes, pesquisa de Escherichia coli e de Salmonella spp., bem como procedeu-se a identificação das leveduras isoladas e o teste de resistência frente a diferentes concentrações do conservante sorbato de potássio. De acordo com o check - list aplicado para verificação das BPF, 70,0% dos estabelecimentos apresentaram não conformidades superiores a 25,0%, sendo classificados como insatisfatórios para produção de alimentos...(Resumo completo clicar acesso eletrônico abaixo) / Abstract: The aim of this work was to verify the Good Manufacturing Practices (GMP) and the microbiologic quality of the salads added of mayonnaise marketed in São José do Rio Preto - SP, through the following analyses: check - list application, based on the legislation in force in the country, which classified the levels of suitability presented by the producers, counting of mould and yeast, Staphylococcus aureus, determining the Most Probable Number of total and heat resistant coliforms, Escherichia coli and Salmonella spp research, and proceeded to identification isolated yeast and resistance test to different concentrations of potassium sorbate conserver. According to the check - list applied to GMP verification, 70,0% of the establishments showed no conformities above 25,0%, being classified as unsatisfactory for food production. The obtained result for mould and yeast counting varied from 1,9 x 103 to 6,0 x 106.. The biggest number of mayonnaise salad contamination was caused by Staphylococcus aureus with variations of < 100 a 1,8 x 107 UFC/g. For The Most Probable Number determination of total and heat resistant coliforms a variation of < 3 a > 1100 NMP/g was verified. Escherichia coli was found in all samples positive for heat resistantt coliforms. Salmonella spp. was not found. From the ten establishments 4 (40%) improved the salads quality with mayonnaise added and 1 (10%) stopped this food production after inspection and the technicians of Sanitary Survellance guidance. In relation to the isolated yeasts, Debaryomyces hansenii var. fabryii species was the most frequent, in 19 cultures (76,0%) followed by Cryptococcus laurentii with 4 (16%), Arxula adeninovorans with 1 (4,0%). The species Arxula adeninovorans and Candida edax were not sensitive to potassium sorbate conserver. In relation to...(Complete abstract click electronic access below) / Mestre

Page generated in 0.4465 seconds