Peppermint, Mentha piperita 'Black Mitcham' was established as a host for tomato spotted wilt virus-impatiens serotype (TSWV-I). TSWV-I infection of peppermint, initially observed in a research greenhouse (Corvallis, OR), included stunting and downward curling of leaves accompanied by bronzing, and occasionally tip necrosis. Young leaves appeared either symptomless, deformed, or pale even under high nitrogen conditions. Older leaves had sunken, brownish-grey lesions. Bright yellow mottling was observed on newly mature deep green leaves. A begonia isolate of TSWV-I was transmitted to peppermint both mechanically and by western flower thrips, Frankliniella occidentalis (Pergande). Symptoms of TSWV-I infection were similar although only a faint yellow mottling was produced and only under cool temperatures (15°C). ELISA detection of virus distribution throughout the plant indicated infection was systemic. Bulked groups of thrips (5 thrips/sample) also tested positive for TSWV-I using ELISA. Transmission efficiency of 4, 6, 8, and 10 day old thrips adults given acquisition sources during the entire nymphal stage varied from 0-40% for thrips tested in pairs and 0-20% for single thrips (based on a 12 hour access feeding period). Adults 2 days old failed to transmit the virus. Western flower thrips exposed to TSWV-I had reduced survival and reproductive potential and slower development rates than unexposed thrips. Virusexposed thrips were 1.4 times as likely to die than unexposed thrips on a given day. Both individual and population reproductive potentials were significantly lower. Preoviposition period was extended in virus-exposed thrips. Development time from second instar to adult was 15% longer for virus-exposed thrips. This is the first report of altered population parameters in western flower thrips exposed to TSWV-I. / Graduation date: 1992

The research undertaken in this thesis includes microwave-assisted extraction (MAE), synthesis, and the investigation of the scale-up of the microwave-assisted processes with the numerical aid. / The main goal of this research is to study the various problems associated with the scale-up of the microwave-assisted extraction and synthesis processes. Laboratory studies were carried out to investigate the microwave-assisted extraction of known components from peppermint leaves and American ginseng. Various factors that influence the extraction processes were studied. Microwave-assisted extraction method was compared with conventional heating and room temperature extraction methods on the extraction of ginsenosides from American ginseng. Microwave-assisted extraction method was determined to have higher extraction rate than both room temperature extraction and reflux temperature extraction using hotplate heating indicating that there is acceleration factor in enhancing the extraction rate beyond the temperature influence. / In the study of synthesizing n-butyl paraben, microwave-assisted synthesis was observed to greatly increase the yield of n-butyl paraben in much shorter period of time compared to the classic synthesis method. A transition state theory was proposed to explain this rate enhancement. The study of the synthesis of parabens with different alcohol and the influencing factors on the synthesis of n-butyl paraben yield were also studied. / A visualization method was developed to determine the microwave distribution in a domestic microwave cavity. The method uses gypsum plate as carrier and cobalt chloride as indictor. A simulation program was developed using the finite difference time domain (FDTD) approach and written in C programming language. The program was proved to be very versatile in different type of cavity simulation. Not only cavities with different dimensions and geometrical designs can be simulated, multiple magnetrons and various ways of magnetron placement can also be integrated into the simulation program. The detailed power distribution can be visualized in a 3-D plot, and the power distribution in each layer can be analyzed using the simulation result. The power distribution information will be very useful and necessary before any real equipment development.

Made available in DSpace on 2017-07-10T19:25:12Z (GMT). No. of bitstreams: 1 priscila.pdf: 1624852 bytes, checksum: cc2a0f1c77b464486310e190671aeeb2 (MD5) Previous issue date: 2012-02-09 / The species Mentha piperita, popularly known as peppermint as well as being a medicinal plant, can be used to obtain flavoring, tea infusions and spices for pharmaceutical, food and cosmetics use. Thus, drying process is necessary to increase the shelf life of the product and facilitate its transport, handling and storage. Due to the aimed good mint quality, it is necessary to study the pre-and post-harvest. The objective of this study was the evaluation of drying the curves of drying mint, by mathematical modeling, in the range of 30 to 70 °C with temperature variation of the drying air velocity of 0.3 and 0.5 m.s-1 and quality analysis of the obtained product. To carry out the drying of leaves, we used a fixed bed dryer at a laboratory scale, which has a fan for air movement and a heating system. There were two analysis regarding the quality, essential oil yield and analysis of color. The results showed that the model Midilli is the one that best fits to the experimental data. The temperature has some influence on the drying process, but the speed had no effect on the analysis of essential oil yield nor on the color of the leaves. The temperature at 50 °C proved to be most suitable for drying of the species, because it presented the highest yield of essential oil and preservation of the green color. / A espécie Mentha piperita, conhecida popularmente como hortelã-pimenta, além de ser considerada uma planta medicinal, pode ser utilizada para obtenção de aromatizantes, infusões de chá e temperos. É amplamente utilizada nas indústrias farmacêuticas, alimentícia e cosméticos. Por estas razões, é necessário o correto processo de secagem, aumentando o tempo de conservação e a vida útil do produto, facilitando seu transporte, manuseio e armazenamento. Para que os derivados da hortelã tenham qualidade, são necessários estudos sobre a pré e a pós-colheita. Objetivou-se neste estudo a avaliação da secagem e a obtenção das curvas de secagem da hortelã, por meio de modelagem matemática, no intervalo de 30 a 70 oC de temperaturas, com variação da velocidade do ar de secagem 0,3 e 0,5 m.s-1 e análise da qualidade do produto obtido. Para a secagem das folhas, foi utilizado um secador de leito fixo em escala de laboratório, o qual possui um ventilador para a movimentação do ar e sistema de aquecimento. Foram realizadas duas análises referentes à qualidade, ao rendimento do óleo essencial e à análise da cor. Os resultados evidenciaram que o modelo de Midili é o que melhor se ajusta aos dados experimentais. A temperatura influenciou o processo de secagem, porém a velocidade não apresentou influência para as análises do rendimento do óleo essencial e nem para a coloração das folhas. A temperatura de 50 oC mostrou-se a mais indicada para a secagem da espécie, pois apresentou o maior rendimento de óleo essencial e a preservação da cor verde.

Made available in DSpace on 2017-05-12T14:48:36Z (GMT). No. of bitstreams: 1 priscila.pdf: 1624852 bytes, checksum: cc2a0f1c77b464486310e190671aeeb2 (MD5) Previous issue date: 2012-02-09 / The species Mentha piperita, popularly known as peppermint as well as being a medicinal plant, can be used to obtain flavoring, tea infusions and spices for pharmaceutical, food and cosmetics use. Thus, drying process is necessary to increase the shelf life of the product and facilitate its transport, handling and storage. Due to the aimed good mint quality, it is necessary to study the pre-and post-harvest. The objective of this study was the evaluation of drying the curves of drying mint, by mathematical modeling, in the range of 30 to 70 °C with temperature variation of the drying air velocity of 0.3 and 0.5 m.s-1 and quality analysis of the obtained product. To carry out the drying of leaves, we used a fixed bed dryer at a laboratory scale, which has a fan for air movement and a heating system. There were two analysis regarding the quality, essential oil yield and analysis of color. The results showed that the model Midilli is the one that best fits to the experimental data. The temperature has some influence on the drying process, but the speed had no effect on the analysis of essential oil yield nor on the color of the leaves. The temperature at 50 °C proved to be most suitable for drying of the species, because it presented the highest yield of essential oil and preservation of the green color. / A espécie Mentha piperita, conhecida popularmente como hortelã-pimenta, além de ser considerada uma planta medicinal, pode ser utilizada para obtenção de aromatizantes, infusões de chá e temperos. É amplamente utilizada nas indústrias farmacêuticas, alimentícia e cosméticos. Por estas razões, é necessário o correto processo de secagem, aumentando o tempo de conservação e a vida útil do produto, facilitando seu transporte, manuseio e armazenamento. Para que os derivados da hortelã tenham qualidade, são necessários estudos sobre a pré e a pós-colheita. Objetivou-se neste estudo a avaliação da secagem e a obtenção das curvas de secagem da hortelã, por meio de modelagem matemática, no intervalo de 30 a 70 oC de temperaturas, com variação da velocidade do ar de secagem 0,3 e 0,5 m.s-1 e análise da qualidade do produto obtido. Para a secagem das folhas, foi utilizado um secador de leito fixo em escala de laboratório, o qual possui um ventilador para a movimentação do ar e sistema de aquecimento. Foram realizadas duas análises referentes à qualidade, ao rendimento do óleo essencial e à análise da cor. Os resultados evidenciaram que o modelo de Midili é o que melhor se ajusta aos dados experimentais. A temperatura influenciou o processo de secagem, porém a velocidade não apresentou influência para as análises do rendimento do óleo essencial e nem para a coloração das folhas. A temperatura de 50 oC mostrou-se a mais indicada para a secagem da espécie, pois apresentou o maior rendimento de óleo essencial e a preservação da cor verde.

Filmes à base de polímeros contendo compostos com atividade antioxidante, podem ser usados na produção de embalagem ativa, que interagem com o alimento contribuindo na sua conservação e no prolongamento da vida de prateleira de alimentos ricos em componentes sensíveis ao oxigênio. Os extratos vegetais são ricos em polifenóis, conhecidos por sua atividade antioxidante e são uma alternativa ao uso dos antioxidantes sintéticos. Assim, o objetivo principal desta tesa foi o desenvolvimento de filmes à base de gelatina adicionados de extratos vegetais, com propriedades físicas e funcionais para seu emprego como embalagens bioativas. Foram produzidos extratos aquosos de sementes de guaraná (Paullinia cupana Kunth), folha de amoreira preta (Morus nigra L.), carqueja (Baccharis trimera), hortelã (Mentha piperita) e folha de pitangueira (Eugenia uniflora L.). Os extratos produzidos em três temperaturas (30, 45 e 60 °C) foram caracterizados quanto a sua cor instrumental, teor de sólidos solúveis, matéria seca, pH, composição proximal e em relação a sua atividade antioxidante (capacidade redutora, DPPH e ABTS). Os extratos que apresentaram maiores atividades antioxidantes foram utilizados na produção dos filmes. Os filmes foram produzidos pela técnica casting com 8 g de gelatina/100g de solução e glicerol (30 g de glicerol/100 g de gelatina) como plastificante. A quantidade de extrato adicionada foi estudada (0, 50 e 150 g de extrato/100 g de gelatina) para a obtenção das melhores propriedades antioxidantes. Os filmes foram submetidos às seguintes caracterizações: espessura, umidade, solubilidade, cor, opacidade, brilho, permeabilidade ao vapor de água, propriedades mecânicas (tração e perfuração), microestrutura (espectroscopia de força atômica e microscopia eletrônica de varredura), propriedades térmicas (DSC), estrutura química com uso de espectroscopia no infravermelho com transformada de Fourier e determinação da atividade antioxidante (capacidade redutora, DPPH e ABTS). O estudo demonstrou que as amostras vegetais analisadas e as temperaturas de extração escolhidas foram eficientes na produção de extratos com atividade antioxidante, sendo possível sua utilização para produção de filmes ativos. Os extratos que apresentaram maiores atividades antioxidantes foram os extratos de folha de pitangueira, semente de guaraná e hortelã, extraídos a 60 °C, sendo estes escolhidos para a produção dos filmes. Para a caracterização dos filmes, a adição dos extratos em geral não afetou nas propriedades mecânicas (tração e perfuração), umidade e solubilidade, não existindo diferença significativa entre os filmes controles sem extratos e os com extratos. A cor dos filmes sofreu influência na adição dos extratos, sendo que filmes acrescidos com os extratos apresentaram uma tendência mais escura e amarelada que os filmes controles. Entretanto, observou-se que, como esperado, os filmes com extratos demonstraram um aumento na atividade antioxidante e propriedades de barreira, sendo os acrescidos com extrato de folha de pitangueira, os que apresentaram melhores resultados. / Films based on biopolymers containing compounds with antioxidant activity can be used to produce active packaging, which interact with the food, contributing to it conservation and the increasing of the shelf life of the food rich in compounds oxygen sensitive. Plant extracts are rich in polyphenols, known for their antioxidant capacity and are an alternative to the use of synthetic antioxidants. Thus, the general goal of this thesis was to develop gelatin-based films added with vegetal extracts, with physical and functional properties for their use as bioactive packaging. Liquid extracts of Guarana (Paullinia cupana Kunth) seeds, mulberry (Morus nigra L.) leaves carqueja (Baccharis trimera.), peppermint (Mentha piperita) and pitanga (Eugenia uniflora L.) leaves were produced. The extracts produced in three temperatures (30, 45 and 60 °C) were characterized by their antioxidant capacity (total phenols, DPPH and ABTS), instrumental color, soluble solids, dry matter, pH and proximal composition. The extracts with the highest antioxidant activity were used in the film\'s production. The films were produced by the casting technique with 8 g of gelatin / 100 g of solution and glycerol (30 g of glycerol/100 g of gelatin) as plasticizer. The amount of extract added to studied the antioxidant properties were : 0, 50 and 150 g of extract / 100 g of gelatin. The films were subjected to the following characterizations: thickness, mechanical properties (traction and perforation), color, opacity, gloss, humidity, solubility, water vapor permeability, microstructure (Atomic force spectroscopy and scanning electron microscopy), thermal properties (DSC), determination of the antioxidant capacity, determination of reducing capacity and chemical structure using Fourier transform infrared spectroscopy. The study demonstrated that the analyzed plant samples and the chosen extraction temperatures were efficient in the production of extracts with antioxidant activity, being possible its use for the production of active films. Extracts of pitanga leaves, guarana seed and peppermint, produced at 60 °C, were chosen due to their high antioxidant activity. In general, the characterization of the films shown that the addition of the extracts did not affect in the mechanical, solubility and humidity properties, having no significant difference between the control films, with no extract, and those with extracts. The colour of the films were influenced by the addiction of the extract, with the increase of darkness and yellowness of the films, when films were added with the extracts. As expected, it was observed that the films with extracts showed an increase in the antioxidant capacity and barrier properties, being that films added with extracts of pitanga leaves presented the better results.

Steam distillation is the traditional method used for the extraction of peppermint oil. This process is able to remove approximately 20% of the oils from the leaves of the plant. It is a very costly and un-sustainable process due to the release of carbon emissions. Solvent free microwave extraction promises yields of up to 65% of the "available" oils from the peppermint at 3% less cost (Velasco 2007). It can also reduce carbon emissions because it will be using electricity as a power source instead of fossil fuels, however not all electric companies use renewable energies. In 2009 a SFME pilot plant was assembled in North Carolina to test the efficiency of the microwave process on a larger than lab scale. Results from the experiments showed that the tube and shell condenser was unable to effectively condense the mint oil. The problem was determined to be the addition of air to the mixture due to the open ends of the microwave. However it was discovered that the spray scrubber after the condenser was able to collect a visible amount of oil. This inspired the design of a direct contact condenser (Pommerenck 2012). The direct contact condenser they designed, built, and tested showed vast improvements in steam capturing efficiency when compared to a tube and shell condenser. However due to the materials used for its construction it could not sustain operating temperatures seen in the microwave pilot plant. Using their design a new direct contact condenser was built using materials that would be able to withstand heavy temperatures. The condenser was constructed out of aluminum and contained stainless steel spray nozzles, both for their non-corrosive properties. Tests were conducted using 8 and 16 nozzles and tested over a range of 20-100% steam by mass. Additional tests were completed using the full 24 nozzles but due to the location of some of the nozzles coolant was lost as an aerosol with no way to quantify the loss. Comparing the data to research completed by Pommerenck et al. on efficiency of a tube and shell condenser used for the mint distillation process found that with increasing amounts of air there is a greater loss of heat transfer. This is believed to be the effects of a boundary layer of the noncondensable fluid, air, which forms along the tube and resists condensation from forming (Seunguim 2006). Pommerenck's tube and shell condenser used a coolant flow rate of 24 L/min while the flow rates tested in this research were 18 L/min and 36 L/min. The direct contact condenser showed a considerable increase in performance even with the smaller flow rate compared to the tube and shell unit, indicating removal of the boundary layer. The efficiency tends to follow the maximum theoretical efficiency while the tube and shell condenser lowers in efficiency. The overall goal of this project is to determine the feasibility of the use of a direct contact condenser for implementation in the solvent free microwave extraction of peppermint oil when air is present. / Graduation date: 2012

Filmes à base de polímeros contendo compostos com atividade antioxidante, podem ser usados na produção de embalagem ativa, que interagem com o alimento contribuindo na sua conservação e no prolongamento da vida de prateleira de alimentos ricos em componentes sensíveis ao oxigênio. Os extratos vegetais são ricos em polifenóis, conhecidos por sua atividade antioxidante e são uma alternativa ao uso dos antioxidantes sintéticos. Assim, o objetivo principal desta tesa foi o desenvolvimento de filmes à base de gelatina adicionados de extratos vegetais, com propriedades físicas e funcionais para seu emprego como embalagens bioativas. Foram produzidos extratos aquosos de sementes de guaraná (Paullinia cupana Kunth), folha de amoreira preta (Morus nigra L.), carqueja (Baccharis trimera), hortelã (Mentha piperita) e folha de pitangueira (Eugenia uniflora L.). Os extratos produzidos em três temperaturas (30, 45 e 60 °C) foram caracterizados quanto a sua cor instrumental, teor de sólidos solúveis, matéria seca, pH, composição proximal e em relação a sua atividade antioxidante (capacidade redutora, DPPH e ABTS). Os extratos que apresentaram maiores atividades antioxidantes foram utilizados na produção dos filmes. Os filmes foram produzidos pela técnica casting com 8 g de gelatina/100g de solução e glicerol (30 g de glicerol/100 g de gelatina) como plastificante. A quantidade de extrato adicionada foi estudada (0, 50 e 150 g de extrato/100 g de gelatina) para a obtenção das melhores propriedades antioxidantes. Os filmes foram submetidos às seguintes caracterizações: espessura, umidade, solubilidade, cor, opacidade, brilho, permeabilidade ao vapor de água, propriedades mecânicas (tração e perfuração), microestrutura (espectroscopia de força atômica e microscopia eletrônica de varredura), propriedades térmicas (DSC), estrutura química com uso de espectroscopia no infravermelho com transformada de Fourier e determinação da atividade antioxidante (capacidade redutora, DPPH e ABTS). O estudo demonstrou que as amostras vegetais analisadas e as temperaturas de extração escolhidas foram eficientes na produção de extratos com atividade antioxidante, sendo possível sua utilização para produção de filmes ativos. Os extratos que apresentaram maiores atividades antioxidantes foram os extratos de folha de pitangueira, semente de guaraná e hortelã, extraídos a 60 °C, sendo estes escolhidos para a produção dos filmes. Para a caracterização dos filmes, a adição dos extratos em geral não afetou nas propriedades mecânicas (tração e perfuração), umidade e solubilidade, não existindo diferença significativa entre os filmes controles sem extratos e os com extratos. A cor dos filmes sofreu influência na adição dos extratos, sendo que filmes acrescidos com os extratos apresentaram uma tendência mais escura e amarelada que os filmes controles. Entretanto, observou-se que, como esperado, os filmes com extratos demonstraram um aumento na atividade antioxidante e propriedades de barreira, sendo os acrescidos com extrato de folha de pitangueira, os que apresentaram melhores resultados. / Films based on biopolymers containing compounds with antioxidant activity can be used to produce active packaging, which interact with the food, contributing to it conservation and the increasing of the shelf life of the food rich in compounds oxygen sensitive. Plant extracts are rich in polyphenols, known for their antioxidant capacity and are an alternative to the use of synthetic antioxidants. Thus, the general goal of this thesis was to develop gelatin-based films added with vegetal extracts, with physical and functional properties for their use as bioactive packaging. Liquid extracts of Guarana (Paullinia cupana Kunth) seeds, mulberry (Morus nigra L.) leaves carqueja (Baccharis trimera.), peppermint (Mentha piperita) and pitanga (Eugenia uniflora L.) leaves were produced. The extracts produced in three temperatures (30, 45 and 60 °C) were characterized by their antioxidant capacity (total phenols, DPPH and ABTS), instrumental color, soluble solids, dry matter, pH and proximal composition. The extracts with the highest antioxidant activity were used in the film\'s production. The films were produced by the casting technique with 8 g of gelatin / 100 g of solution and glycerol (30 g of glycerol/100 g of gelatin) as plasticizer. The amount of extract added to studied the antioxidant properties were : 0, 50 and 150 g of extract / 100 g of gelatin. The films were subjected to the following characterizations: thickness, mechanical properties (traction and perforation), color, opacity, gloss, humidity, solubility, water vapor permeability, microstructure (Atomic force spectroscopy and scanning electron microscopy), thermal properties (DSC), determination of the antioxidant capacity, determination of reducing capacity and chemical structure using Fourier transform infrared spectroscopy. The study demonstrated that the analyzed plant samples and the chosen extraction temperatures were efficient in the production of extracts with antioxidant activity, being possible its use for the production of active films. Extracts of pitanga leaves, guarana seed and peppermint, produced at 60 °C, were chosen due to their high antioxidant activity. In general, the characterization of the films shown that the addition of the extracts did not affect in the mechanical, solubility and humidity properties, having no significant difference between the control films, with no extract, and those with extracts. The colour of the films were influenced by the addiction of the extract, with the increase of darkness and yellowness of the films, when films were added with the extracts. As expected, it was observed that the films with extracts showed an increase in the antioxidant capacity and barrier properties, being that films added with extracts of pitanga leaves presented the better results.

The peppermint (Mentha piperita), the salvia (Salvia officinalis), the lemon balm (Melissa oficinalis), the camomile (Matricaria chamomilla) and the valerian (Valeriana officinalis) are herbs with healing effects. Their ethanol extracts are used for food fortification or in a cosmetic industry. Substances contained in herbal extracts were analyzed in this thesis. The extracts were prepared by maceration. Next, they were analyzed by using a gas chromatography and a mass spectrometry. The aim of this thesis was an optimalization of the method used for the analysis of sensorially active substances. Then, herbal extracts were analyzed and concentration of sensorially active substances was determined.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal