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  • 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

Privacy Preserving Data Mining Operations without Disrupting Data Quality

B.Swapna, R.VijayaPrakash 01 December 2012 (has links)
Data mining operations have become prevalent as they can extract trends or patterns that help in taking good business decisions. Often they operate on large historical databases or data warehouses to obtain actionable knowledge or business intelligence that helps in taking well informed decisions. In the data mining domain there came many tools to perform data mining operations. These tools are best used to obtain actionable knowledge from data. Manually doing this is not possible as the data is very huge and takes lot of time. Thus the data mining domain is being improved in a rapid pace. While data mining operations are very useful in obtaining business intelligence, they also have some drawbacks that are they get sensitive information from the database. People may misuse the freedom given by obtaining sensitive information illegally. Preserving privacy of data is also important. Towards this end many Privacy Preserving Data Mining (PPDM) algorithms came into existence that sanitize data to prevent data mining algorithms from extracting sensitive information from the databases. / Data mining operations help discover business intelligence from historical data. The extracted business intelligence or actionable knowledge helps in taking well informed decisions that leads to profit to the organization that makes use of it. While performing mining privacy of data has to be given utmost importance. To achieve this PPDM (Privacy Preserving Data Mining) came into existence by sanitizing database that prevents discovery of association rules. However, this leads to modification of data and thus disrupting the quality of data. This paper proposes a new technique and algorithms that can perform privacy preserving data mining operations while ensuring that the data quality is not lost. The empirical results revealed that the proposed technique is useful and can be used in real world applications.
2

Quality and Sensory Attributes of Shell Eggs Sanitized with a Combination of Hydrogen Peroxide and Ultraviolet Light

Woodring, Kristy Senise 2011 August 1900 (has links)
Two experiments were conducted to evaluate the combination of hydrogen peroxide (H2O2) and ultraviolet light (UV) as an alternative eggshell sanitization procedure for shell egg processing. In each experiment, two cases of eggs (720 total) were collected at a commercial inline egg production facility. To assure egg uniformity, only eggs between 57 and 62 g were collected from a single hen house. Half of the eggs (360) were commercially processed (washer and sanitizing rinse) following normal procedures outlined by the U.S. Department of Agriculture (USDA) for shell egg processing (control group). The other half of the eggs (360) were washed as normal but without the sanitizing rinse. These eggs were then treated with 3 percent H2O2 and UV light (treated group). The treatment consisted of spraying the eggs with 3 percent H2O2 over the entire shell surface followed immediately by exposure to UV light for 5 s in an enclosed chamber equipped with germicidal lamps (UV-C). This treatment was performed twice. Eggshell aerobic plate counts (APC), eggshell breaking strength and thickness, albumen height and pH, Haugh units, and yolk color were measured after 1, 15, 30, 45, and 60 days of storage. On d 15 and 45, sensory evaluation of scrambled egg samples was conducted to determine if consumers could detect a difference between treatment groups using a triangle test. Results indicate APC for treated eggs were significantly lower than the control eggs for all sampling days in Experiment 1. However, due to low initial APC in the control eggs on d 1 of Experiment 2, no significant differences were observed for APC between control and treated eggs during storage. No consistent differences were found for eggshell and interior quality measures with the exception of albumen pH. Albumen pH was significantly higher in treated eggs than control on d 45 and 60 and d 1, 15, and 45 of Experiment 1 and 2, respectively, with only an average difference of 0.04 pH. In the sensory evaluation, only 33.5 percent of the participants correctly differentiated between the control and treated eggs. Data from this study suggests that H2O2 and UV light can be used as an alternative eggshell sanitizing procedure without impacting eggshell or internal egg quality.
3

Decontamination of Food Processing Equipment Contaminated with Biofilm-forming Pseudomonas spp. by Ozone-based Cleaning-in-place

Tirpanci, Goksel 19 December 2011 (has links)
No description available.
4

The prevalence and mode of persistence of Salmonella on commercial poultry processing equipment after sanitization procedures

Obe, Tomilola Olofunke 07 August 2020 (has links)
The prevalence and mode of persistence of Salmonella on commercial poultry processing equipment was examined in this study. The equipment surfaces of six commercial processing plants were sampled over three-time periods designated as A (after processing), B (after cleaning), and C (after sanitization) and each plant was visited three times. Salmonella prevalence was greater (p<0.0001) at time A than times B and C, while there were no differences (p=0.386) between times B and C. A total of twentyive Salmonella isolates from five distinct serovars were recovered from the processing plants. Further examination of the recovered isolates showed that tolerance to sanitizing agents (chlorine and quaternary ammonium compounds, QAC) and/or biofilm formation was the possible mode of persistence. In addition, all the isolates were resistant to multiple antibiotics in different classes of drugs and more than two genes that are responsible for ⅰ). biofilm formation, ⅱ). resistance to QAC, ⅲ). oxidative stress response, and ⅳ). resistance to antibiotics were detected. Three selected isolates were further characterized based on virulence factors and antimicrobial resistance using whole genome sequencing (WGS) to possibly predict phenotypic characteristics. The WGS data correlates with phenotypic characteristics that were previously observed in the isolates including the ability to produce biofilms and resistance to antibiotics including β-lactams, aminoglycosides, and cephalosporins. WGS predicted the isolates carried resistance genes for antibiotic drug classes that were not observed phenotypically. These include macrolides and fluoroquinolone, which is a concern due to its use in treating foodborne infection. Furthermore, the genome of the three selected isolates were predicted to have over sixty virulence genes that allow Salmonella to invade, attach, and colonize the host cells. The results from this study suggest that the antimicrobials used for sanitization may be insufficient to inactivate Salmonella because of the ability to produce biofilms on processing surfaces. Most importantly, the results suggest the ability of the isolates to cause infection in humans meaning if contamination were to occur, the right antibiotic treatment could be a challenge. Further research is imperative to determine the effective antimicrobial for Salmonella biofilms.
5

Estudo da aplicabilidade de técnicas de sanitização de dados em discos rí­gidos atuais. / Study of the applicability of data sanitization techniques on current hard disks.

Sbampato, Fernando Vilgino 23 January 2018 (has links)
A sanitização de dados é um dos desafios que está em aberto quando tange a segurança de dados nos discos rígidos. Há duas formas de realizar este procedimento de sanitização de dados nos discos rígidos. A primeira é a utilização de técnicas físicas que visam à destruição do disco rígido por completo. A segunda é a utilização de técnicas lógicas que visam realizar a sanitização dos dados armazenados no disco, permitindo que este seja reutilizado. A proposta principal deste trabalho é a de verificar por meio da técnica de Microscopia de Força Magnética (MFM) a possibilidade de recuperação dos dados originais após o processo de sanitização ter ocorrido por meio de uma técnica lógica. Com este objetivo foram selecionadas oito técnicas lógicas (Gutmann, VSITR, RCMP TSSIP OPS-II, CSEC ITSG-06, DoD 5220.22-M, AR 280-19, GOST R 50739-95 e ISM 6.9.92), após esta seleção foi realizada uma avaliação lógica dessas técnicas com o intuito de selecionar duas técnicas para a avaliação experimental. Para realizar a avaliação experimental foram utilizados dois microscópios (Dimension Icon e o MultiMode 8) para aplicar a técnica de MFM em disco rígido. O objetivo foi comprovar a eficiência das técnicas lógicas na sanitização de dados armazenados nos discos rígidos. / Data sanitization is one of the challenges you face when it comes to data security on hard disk. There are two ways to perform this data sanitization procedure on hard disks. The first one is the deployment of physical techniques aimed at destroying the hard drive altogether. The second one is the use of logical techniques that aim to sanitize the data stored on the disk, allowing it to be used again. The main purpose of this work is to verify through the Magnetic Force Microscopy technique (MFM) the possibility of recovering of the original data after the sanitization process has occurred through of a logical technique. To this purpose, eight logics (Gutmann, VSITR, RCMP TSSIP OPS-II, CSEC ITSG-06, DoD 5220.22-M, AR 280-19, GOST R 50739-95 and ISM 6.9.92) were selected. After this selection, a logical evaluation of these techniques was carried out for selecting two techniques for the experimental evaluation. To perform the experimental evaluation, two microscopes (Dimension Icon and MultiMode 8) were used to apply the MFM technique to the hard disk. The objective was to verify the efficiency of the logical techniques in the sanitization of data stored in the hard disks.
6

Estudo da aplicabilidade de técnicas de sanitização de dados em discos rí­gidos atuais. / Study of the applicability of data sanitization techniques on current hard disks.

Fernando Vilgino Sbampato 23 January 2018 (has links)
A sanitização de dados é um dos desafios que está em aberto quando tange a segurança de dados nos discos rígidos. Há duas formas de realizar este procedimento de sanitização de dados nos discos rígidos. A primeira é a utilização de técnicas físicas que visam à destruição do disco rígido por completo. A segunda é a utilização de técnicas lógicas que visam realizar a sanitização dos dados armazenados no disco, permitindo que este seja reutilizado. A proposta principal deste trabalho é a de verificar por meio da técnica de Microscopia de Força Magnética (MFM) a possibilidade de recuperação dos dados originais após o processo de sanitização ter ocorrido por meio de uma técnica lógica. Com este objetivo foram selecionadas oito técnicas lógicas (Gutmann, VSITR, RCMP TSSIP OPS-II, CSEC ITSG-06, DoD 5220.22-M, AR 280-19, GOST R 50739-95 e ISM 6.9.92), após esta seleção foi realizada uma avaliação lógica dessas técnicas com o intuito de selecionar duas técnicas para a avaliação experimental. Para realizar a avaliação experimental foram utilizados dois microscópios (Dimension Icon e o MultiMode 8) para aplicar a técnica de MFM em disco rígido. O objetivo foi comprovar a eficiência das técnicas lógicas na sanitização de dados armazenados nos discos rígidos. / Data sanitization is one of the challenges you face when it comes to data security on hard disk. There are two ways to perform this data sanitization procedure on hard disks. The first one is the deployment of physical techniques aimed at destroying the hard drive altogether. The second one is the use of logical techniques that aim to sanitize the data stored on the disk, allowing it to be used again. The main purpose of this work is to verify through the Magnetic Force Microscopy technique (MFM) the possibility of recovering of the original data after the sanitization process has occurred through of a logical technique. To this purpose, eight logics (Gutmann, VSITR, RCMP TSSIP OPS-II, CSEC ITSG-06, DoD 5220.22-M, AR 280-19, GOST R 50739-95 and ISM 6.9.92) were selected. After this selection, a logical evaluation of these techniques was carried out for selecting two techniques for the experimental evaluation. To perform the experimental evaluation, two microscopes (Dimension Icon and MultiMode 8) were used to apply the MFM technique to the hard disk. The objective was to verify the efficiency of the logical techniques in the sanitization of data stored in the hard disks.
7

Data Protection and Data Elimination

Budd, Chris 10 1900 (has links)
ITC/USA 2015 Conference Proceedings / The Fifty-First Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2015 / Bally's Hotel & Convention Center, Las Vegas, NV / Data security is becoming increasingly important in all areas of storage. The news services frequently have stories about lost or stolen storage devices and the panic it causes. Data security in an SSD usually involves two components: data protection and data elimination. Data protection includes passwords to protect against unauthorized access and encryption to protect against recovering data from the flash chips. Data elimination includes erasing the encryption key and erasing the flash. Telemetry applications frequently add requirements such as write protection, external erase triggers, and overwriting the flash after the erase. This presentation will review these data security features.
8

Alface orgânica: avaliação microbiológica relacionada ao sistema de produção e processamento mínimo e estudo de sua aceitação sensorial / Organic lettuce: microbiological evaluation related to production and minimal processing and its sensory acceptance study

Rizzo, Denise Lutgens 23 April 2014 (has links)
Hortaliças são identificadas como veículos de patógenos, especialmente Escherichia coli e Salmonella sp. e surtos recentes revelam crescente número de casos associados a seu consumo. A sanitização pode evitar contaminações, mas não atinge patógenos internalizados na planta e, além disso, pode não ter efeito ao longo da vida útil do produto. Amostrar superfícies pode ampliar a amostragem, especialmente para patógenos humanos de comportamento errático. Após sanitização, perda de qualidade sensorial e uso de produtos químicos podem ser fatores de rejeição de produto por parte do consumidor de orgânicos. Foram objetivos: 1 - Quantificar a microbiota presente sobre folhas de alface antes da colheita, 2 - Rastrear possíveis pontos de contaminação nas propriedades rurais, 3 - Avaliar o efeito da sanitização de alface em sua qualidade microbiológica e sensorial, 4 - Verificar o impacto do preço, conveniência e presença de selo de certificação orgânica sobre a intenção de compra de alface. Para coleta de microrganismos de folhas, mãos, caixas, bancadas e utensílios que entram em contato com a produção, em 10 propriedades rurais, esponjas de celulose embebidas em água peptonada tamponada foram utilizadas para recuperar microrganismos. Análises sensoriais e microbiológicas foram realizadas durante o período de armazenamento de alfaces refrigeradas a 8ºC, até 9 dias após colheita, comparando os seguintes procedimentos: 1 - Lavagem com água da rede e sanitização com dicloroisocianurato de sódio dihidratado; 2 - Lavagem com água da rede e sanitização com oxicloreto de cálcio; 3 - Lavagem em água da rede, sem sanitização; e 4 - Sem lavagem e sem sanitização. As técnicas sensoriais utilizadas para verificar aspectos de aceitação do produto pelo consumidor e explorar seu comportamento de compra foram: Conjoint Analysis, associação de palavras, escala de atitude orgânica. Duas pesquisas foram realizadas, sendo uma presencial com consumidores com menor conhecimento sobre orgânicos e pesquisa via internet para um grupo de consumidores membros da Associação de Consumidores de Produtos Orgânicos do Paraná ou indicados por estes. Os resultados microbiológicos demonstraram que a população de mesófilos totais é predominante sobre folhas de alface e nas superfícies amostradas. Detectou-se E. coli em superfície de folhas de alface, bancadas de manipulação e caixas de colheita. A presença de Listeria monocytogenes foi detectada em folha de alface, caixa, faca e bancada de manipulação de diferentes produtores. Não foi detectada presença de Salmonella sp. em qualquer das coletas. Para alfaces colhidas e higienizadas com água da rede, e com sanitizantes, as populações de microrganismos diminuíram, mas após sete dias de armazenamento refrigerado, as populações aumentaram chegando a superar os valores iniciais da alface recém-colhida, exceto para S. aureus. Na avaliação sensorial, o tratamento 4 - Sem Lavar e sem sanitização foi significativamente menos aceito (p&lt;0,05) em relação aos atributos odor, frescor, integridade da folha, aspecto geral e intenção de compra que os demais tratamentos, os quais não diferiram entre si. Resultados sobre o comportamento do consumidor, provenientes da Conjoint Analysis, para o grupo com menor conhecimento sobre orgânicos, demonstraram que as importâncias relativas foram 49,49% para preço, 15,85% para selo orgânico e 34,66% para conveniência, indicando a prevalência do preço na decisão de compra, seguido da conveniência. Para a pesquisa com consumidores mais conscientes sobre produção orgânica as importâncias relativas foram 57,3% para preço, 32,4% para selo da certificadora e 10,3% para conveniência, demonstrando que público com maior informação sobre a produção orgânica também valoriza o preço, mas a presença de selo de certificação tem mais valor do que a conveniência. Na tarefa de associação de palavras, mesmo sem o selo oficial, os respondentes associam o produto como orgânico e saudável, poucos citam o aspecto sem certificação. A maior classe de palavras citada é \"caro\", mesmo para o produto de menor preço, demonstrando que a referência de preço é da alface in natura, sem nenhum processamento. / Leaf vegetables have been associated as vehicles for pathogens, especially Escherichia coli and Salmonella sp. and recently many studies report outbreaks linked to their consumption. Sanitization can avoid contamination but can\'t reach internal pathogens. Sampling ofsurfaces can be more efficient for human pathogens with erratic behavior. After sanitization loss of sensorial quality and use of chemicals can cause rejection by consumers of organic products. The objectives were: 1 - To quantify microbiota present on lettuce leaves before harvesting, 2 - To track of possible contamination points at the farm, 3 - To evaluate effect of lettuce sanitization on its microbiological and sensorial quality, 4 - To verify the impact of price, convenience and organic certification of lettuce on buying intention of the product. Collection of microorganisms from leaves, hands, boxes, benches and utensils that have contact with production in 10 farms was performed employing cellulose sponges soaked with buffered peptone water. Sensorial and microbiological analyses were performed in lettuces under refrigerated storage at 8ºC, for up to 9 days after harvesting, comparing the following procedures: 1 - Washing with tap water and sanitizing with sodium dichloroisocyanurate dihydrate; 2 - Washing with tap water and sanitizing with calcium oxychloride; 3 - Washing with tap water without sanitizing; and 4 - Without washing or sanitizing. The sensory methods employed to determine consumer behavior were Conjoint Analysis, word association and organic attitude scale to verify aspects of consumer product acceptance. Two researches were conducted a direct survey with consumers that had less knowledge about organic products and an internet survey for a group of consumers related to an organic consumer association. The microbiological results demonstrate that total mesophiles are the main population found on lettuce leaves and surfaces. E. coli was detected on surfaces of lettuce leaves, handling benches and harvesting boxes. Listeria monocytogenes was detected on lettuce leaves, boxes, knives and handling benches of different producers. Presence of Salmonella sp. was not detected in any of the samples. Microorganism populations reduced in harvested lettuces that were washed in tap water and with sanitizers, but after seven days of storage the microbial counts incresaed even above the initial values of recently harvested lettuces, except for S. aureus. The sensory evaluation results show that treatment 4 - without washing or sanitizing was significantly less accepted (p&lt;0.05) in relation to odor, freshness, leaf integrity, general aspect and buying intention than the other treatments, while all the other treatments presented no significant differences between them. Conjoint Analysis consumer behavior results for the group with less information about organic products demonstrated that the relative importance of the factors were 49.49% for price, 15.85% for organic logo and 34.66% for convenience, indicating that price is the decisive factor for buying lettuce, followed by convenience. The survey with consumers that have more knowledge about organic production the relative importance of the factors were 57.3% for price, 32.4% for certification logo and 10.3% for convenience, which shows that though price is still the most decisive factor, the presence of a certification logo is more important than convenience. The word association task shows that even when the certification logo was not present the product was linked to organic and healthy and only a few mentioned the aspect \"without certification\". The largest group of words is \"expensive\" even for the lowest priced product, indicating that the price reference is that of unprocessed lettuce (in natura).
9

Alface orgânica: avaliação microbiológica relacionada ao sistema de produção e processamento mínimo e estudo de sua aceitação sensorial / Organic lettuce: microbiological evaluation related to production and minimal processing and its sensory acceptance study

Denise Lutgens Rizzo 23 April 2014 (has links)
Hortaliças são identificadas como veículos de patógenos, especialmente Escherichia coli e Salmonella sp. e surtos recentes revelam crescente número de casos associados a seu consumo. A sanitização pode evitar contaminações, mas não atinge patógenos internalizados na planta e, além disso, pode não ter efeito ao longo da vida útil do produto. Amostrar superfícies pode ampliar a amostragem, especialmente para patógenos humanos de comportamento errático. Após sanitização, perda de qualidade sensorial e uso de produtos químicos podem ser fatores de rejeição de produto por parte do consumidor de orgânicos. Foram objetivos: 1 - Quantificar a microbiota presente sobre folhas de alface antes da colheita, 2 - Rastrear possíveis pontos de contaminação nas propriedades rurais, 3 - Avaliar o efeito da sanitização de alface em sua qualidade microbiológica e sensorial, 4 - Verificar o impacto do preço, conveniência e presença de selo de certificação orgânica sobre a intenção de compra de alface. Para coleta de microrganismos de folhas, mãos, caixas, bancadas e utensílios que entram em contato com a produção, em 10 propriedades rurais, esponjas de celulose embebidas em água peptonada tamponada foram utilizadas para recuperar microrganismos. Análises sensoriais e microbiológicas foram realizadas durante o período de armazenamento de alfaces refrigeradas a 8ºC, até 9 dias após colheita, comparando os seguintes procedimentos: 1 - Lavagem com água da rede e sanitização com dicloroisocianurato de sódio dihidratado; 2 - Lavagem com água da rede e sanitização com oxicloreto de cálcio; 3 - Lavagem em água da rede, sem sanitização; e 4 - Sem lavagem e sem sanitização. As técnicas sensoriais utilizadas para verificar aspectos de aceitação do produto pelo consumidor e explorar seu comportamento de compra foram: Conjoint Analysis, associação de palavras, escala de atitude orgânica. Duas pesquisas foram realizadas, sendo uma presencial com consumidores com menor conhecimento sobre orgânicos e pesquisa via internet para um grupo de consumidores membros da Associação de Consumidores de Produtos Orgânicos do Paraná ou indicados por estes. Os resultados microbiológicos demonstraram que a população de mesófilos totais é predominante sobre folhas de alface e nas superfícies amostradas. Detectou-se E. coli em superfície de folhas de alface, bancadas de manipulação e caixas de colheita. A presença de Listeria monocytogenes foi detectada em folha de alface, caixa, faca e bancada de manipulação de diferentes produtores. Não foi detectada presença de Salmonella sp. em qualquer das coletas. Para alfaces colhidas e higienizadas com água da rede, e com sanitizantes, as populações de microrganismos diminuíram, mas após sete dias de armazenamento refrigerado, as populações aumentaram chegando a superar os valores iniciais da alface recém-colhida, exceto para S. aureus. Na avaliação sensorial, o tratamento 4 - Sem Lavar e sem sanitização foi significativamente menos aceito (p&lt;0,05) em relação aos atributos odor, frescor, integridade da folha, aspecto geral e intenção de compra que os demais tratamentos, os quais não diferiram entre si. Resultados sobre o comportamento do consumidor, provenientes da Conjoint Analysis, para o grupo com menor conhecimento sobre orgânicos, demonstraram que as importâncias relativas foram 49,49% para preço, 15,85% para selo orgânico e 34,66% para conveniência, indicando a prevalência do preço na decisão de compra, seguido da conveniência. Para a pesquisa com consumidores mais conscientes sobre produção orgânica as importâncias relativas foram 57,3% para preço, 32,4% para selo da certificadora e 10,3% para conveniência, demonstrando que público com maior informação sobre a produção orgânica também valoriza o preço, mas a presença de selo de certificação tem mais valor do que a conveniência. Na tarefa de associação de palavras, mesmo sem o selo oficial, os respondentes associam o produto como orgânico e saudável, poucos citam o aspecto sem certificação. A maior classe de palavras citada é \"caro\", mesmo para o produto de menor preço, demonstrando que a referência de preço é da alface in natura, sem nenhum processamento. / Leaf vegetables have been associated as vehicles for pathogens, especially Escherichia coli and Salmonella sp. and recently many studies report outbreaks linked to their consumption. Sanitization can avoid contamination but can\'t reach internal pathogens. Sampling ofsurfaces can be more efficient for human pathogens with erratic behavior. After sanitization loss of sensorial quality and use of chemicals can cause rejection by consumers of organic products. The objectives were: 1 - To quantify microbiota present on lettuce leaves before harvesting, 2 - To track of possible contamination points at the farm, 3 - To evaluate effect of lettuce sanitization on its microbiological and sensorial quality, 4 - To verify the impact of price, convenience and organic certification of lettuce on buying intention of the product. Collection of microorganisms from leaves, hands, boxes, benches and utensils that have contact with production in 10 farms was performed employing cellulose sponges soaked with buffered peptone water. Sensorial and microbiological analyses were performed in lettuces under refrigerated storage at 8ºC, for up to 9 days after harvesting, comparing the following procedures: 1 - Washing with tap water and sanitizing with sodium dichloroisocyanurate dihydrate; 2 - Washing with tap water and sanitizing with calcium oxychloride; 3 - Washing with tap water without sanitizing; and 4 - Without washing or sanitizing. The sensory methods employed to determine consumer behavior were Conjoint Analysis, word association and organic attitude scale to verify aspects of consumer product acceptance. Two researches were conducted a direct survey with consumers that had less knowledge about organic products and an internet survey for a group of consumers related to an organic consumer association. The microbiological results demonstrate that total mesophiles are the main population found on lettuce leaves and surfaces. E. coli was detected on surfaces of lettuce leaves, handling benches and harvesting boxes. Listeria monocytogenes was detected on lettuce leaves, boxes, knives and handling benches of different producers. Presence of Salmonella sp. was not detected in any of the samples. Microorganism populations reduced in harvested lettuces that were washed in tap water and with sanitizers, but after seven days of storage the microbial counts incresaed even above the initial values of recently harvested lettuces, except for S. aureus. The sensory evaluation results show that treatment 4 - without washing or sanitizing was significantly less accepted (p&lt;0.05) in relation to odor, freshness, leaf integrity, general aspect and buying intention than the other treatments, while all the other treatments presented no significant differences between them. Conjoint Analysis consumer behavior results for the group with less information about organic products demonstrated that the relative importance of the factors were 49.49% for price, 15.85% for organic logo and 34.66% for convenience, indicating that price is the decisive factor for buying lettuce, followed by convenience. The survey with consumers that have more knowledge about organic production the relative importance of the factors were 57.3% for price, 32.4% for certification logo and 10.3% for convenience, which shows that though price is still the most decisive factor, the presence of a certification logo is more important than convenience. The word association task shows that even when the certification logo was not present the product was linked to organic and healthy and only a few mentioned the aspect \"without certification\". The largest group of words is \"expensive\" even for the lowest priced product, indicating that the price reference is that of unprocessed lettuce (in natura).
10

Pathogen Reduction on Selected Vegetables Using Hydrogen Peroxide

Atuobi Ampadu, Christiana 28 June 2007 (has links)
No description available.

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