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Effect of post-harvest treatment on ripening and quality of tomato fruit using ozone : application of different ozone doses as controlled atmosphere storage for delay ripening and maintaining the quality of tomatoes and effect of ozone on antioxidant and sugar compounds at different stages of tomato fruit ripeningShalluf, Milad A. January 2010 (has links)
Tomatoes are widely produced and consumed due to their nutritional content and versatility. However, the tomato is a soft fruit liable to damage and flavour deterioration. Hence, the main challenge for the tomato producing industry is to prevent the high loss incurred during harvest, handling and transportation of the crops. The objective of this study was to investigate the overall nutritional implication of controlled storage of tomatoes using ozone on the ripening process and the basic nutritional components of tomatoes. This investigation was also designed to focus on the effect of different ozone doses on the basic components and properties (carotenoids, ascorbic acid, total antioxidant activity and soluble sugars content) of the quality and dynamic maturity of tomatoes. Green tomatoes (Rio Grande) were treated in glass chambers with ozone enriched air [(air + 2, 7 and 21 mg O3/g tomato) and control (air only)] under humidity and temperature of 90-95% and 14-17 oC respectively. Tomatoes were sampled after 14 days of ozone treatment in the storage chamber and analyzed for different quality parameters (appearance, weight loss, Total Soluble Solids (TSS), titratable acidity, total ascorbic acid and carotene) of the ripening. The variety Elegance tomatoes were selected and the fruits were graded by colour and subjected to treatment with ozone (in doses 0 (clean air), 0.25, 0.50, and1.00 mg O3/g tomatoes) during storage for 6 days under the same humidity and temperature conditions. The fruits were analysed for carotenoids, ascorbic acid content, total antioxidant activity and soluble sugars. Analysis of the fruits clearly showed that ozone significantly delayed the development of colour on the surface, particularly in the low doses, and caused black spots on the surface of the tomatoes, particularly in higher ozone doses. Ozone did not affect the ascorbic acid and titratable acidity content. However ozone did reduce the Total Soluble Solids (TSS) by about 10% at the lowest ozone dose. A high inhibition of accumulation of carotenoids, particularly at low dose, of the tomatoes (Rio Grande) was also observed. Tomatoes (Elegance) under ozone treatments contained higher ß-carotene than those under the control treatment and lycopene content increased during storage in the red stage of tomato fruits. Ascorbic acid (AsA), dehydroascorbic acid (DHA) and the total of AsA and DHA concentrations, and ratios of redox (ASA/ (ASA + DHA) and DHA/AsA in pericarp and pulp of tomatoes tissue, did not show clear differences between the different treatments. The concentrations of the glucose and fructose increased in the tomatoes which were subjected to ozone treatments. Results from this study show that controlled atmosphere storage of tomatoes using ozone is a viable technique which warrants further study.
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Avaliação da Aplicação Combinada de Quitosana e Óleo Essencial de Cymbopogon citratus DC. Ex Nees para Controle Pós-colheita de Rhizopus stolonifer em tomatesATHAYDE, Ana Júlia A. A. 25 February 2015 (has links)
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Previous issue date: 2015-02-25 / O tomate (Lycopersicon esculentum) é uma das frutas mais populares do mundo, porém, 21%
de sua produção é perdida devido a doenças pós-colheita, especialmente causadas por fungos
patogênicos, como a podridão causada por Rhizopus stolonifer. Para controle de doenças póscolheita,
antimicrobianos naturais, como a quitosana (QUI) e óleos essenciais (OE), vêm
sendo utilizados. Tais compostos apresentam comprovada ação antimicrobiana, além de baixa
toxicidade. Este estudo avaliou a eficácia da aplicação combinada de quitosana (QUI) e óleo
essencial de Cymbopogon citratus Dc. Ex Nees (OECC) para controle de Rhizopus stolonifer
(R. stolonifer) URM 3728 em meio laboratorial e em tomates frescos (Lycopersicon
esculentum Mill.) em temperatura ambiente ao longo de 12 dias. A concentração inibitória
mínima (CIM) da quitosana e do óleo, foi realizada pela técnica de diluição seriada em caldo.
A partir da CIM, diferentes concentrações subinibitórias foram utilizadas nos experimentos
‘in vitro’ para determinação da influência sobre a germinação dos esporos fúngicos (18 horas
de incubação), efeito na integridade de membrana dos esporos fúngicos, crescimento micelial
radial (3 dias de incubação) e efeito na morfologia de hifas fúngicas. Para a aplicação dos
compostos nos frutos, foram determinados o crescimento fúngico superficial e em frutos
artificialmente feridos. Além disso, durante o período de armazenamento avaliou-se também
os efeitos dos tratamentos (QUI e OECC) sobre a microbiota autóctone, bem como sobre
algumas características físico-químicas dos frutos determinantes da qualidade do fruto, tais
como perda de peso, sólidos solúveis, acidez titulável, pH e ácido ascórbico. A concentração
inibitória mínima (CIM) da QUI e OECC contra R. stolonifer foi de 8 mg / mL e 5 μL/mL,
respectivamente. Concentrações subinibitórias de QUI e OECC (QUI: 4 mg / mL; OECC:
1,25 uL / mL) inibiram a germinação de esporos de fungos em até 97,7% e o crescimento
micelial foi completamente inibido. O revestimento composto pelas combinações de QUI e
OECC foram eficazes na prevenção da colonização (infecção) por R. stolonifer em tomates,
entretanto, apresentou baixo efeito curativo da infecção por R. stolonifer nos frutos. O
revestimento também foi eficaz no na inibição da microbiota fúngica autóctone durante o
armazenamento. Em geral, a aplicação de QUI e OECC como revestimento, preserva a
qualidade dos frutos do tomateiro, conforme medido por alguns atributos físico-químicos. A
partir destes resultados, os revestimentos compostos de QUI e OECC podem ser utilizados
como o tratamento pós-colheita promissor para prevenir a infecção por R. stolonifer em
tomates. / Tomato (Lycopersicon esculentum) is one of the most popular fruits in the world. However,
21% of the annual production of tomato fruits is lost due to postharvest diseases, especially
caused by pathogenic fungi as the rot caused by Rhizopus stolonifer. To control of postharvest
diseases, natural antimicrobials have been used, such as chitosan (CHI) and essential oils
(EO). These compounds have proven antimicrobial activity, and low toxicity. This study
evaluated the efficacy of the combined application of chitosan (CHI) and Cymbopogon
citratus Dc. Ex Nees (lemongrass) essential oil (CCEO) to control Rhizopus stolonifer URM
3728 (R. stolonifer) in synthetic media and when inoculated in fresh tomatoes fruits at room
temperature along 12 days. The minimum inhibitory concentration (MIC) of the chitosan and
the essential oil, was performed by the serial dilution technique. From the MIC, subinibitory
different concentrations were used in “in vitro” experiments to determine the influence on the
germination of fungal spores (18 hours incubation), effect on membrane integrity of fungal
spores, radial mycelial growth (90 hours of incubation) and effect on the morphology of
fungal hyphae. On the application in the fruits they were determined superficial fungal growth
and artificially wounded fruits. Furthermore, during the storage period was also evaluated the
effects of treatments (CHI and CCOE) on autochthonous microflora as well as some physicochemical
characteristics of fruits determining the quality of the fruit, such as weight loss,
soluble solids, titratable acidity, pH and ascorbic acid. The Minimum Inhibitory
Concentration (MIC) of CHI and CCEO against R. stolonifer was 8 mg/mL and 5μL/mL,
respectively. Sub-inhibitory concentrations of CHI and CCEO (CHI: 4 mg/mL; CCEO: 1.25
μL/mL) inhibited fungi spore germination up to 97.7% and completely inhibited mycelial
growth. The coating composed of the combinations of CHI and CCEO were effective to
prevent colonization (infection) of R. stolonifer on tomatoes, otherwise, presented weak
curative effect of the R. stolonifer infection in fruits. The coating also controlled the
autochthonous mycoflora in fruits during storage. In general, the application of CHI and
CCEO as a coating preserved the quality of tomato fruits as measured by some
physicochemical attributes. From these results, the coatings composed of CHI and CCEO
could be a promising post-harvest treatment to prevent R. stolonifer infection in tomatoes
fruits.
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Effect of post-harvest treatment on ripening and quality of tomato fruit using ozone. Application of different ozone doses as controlled atmosphere storage for delay ripening and maintaining the quality of tomatoes and effect of ozone on antioxidant and sugar compounds at different stages of tomato fruit ripening.Shalluf, Milad A. January 2010 (has links)
Tomatoes are widely produced and consumed due to their nutritional content and versatility. However, the tomato is a soft fruit liable to damage and flavour deterioration. Hence, the main challenge for the tomato producing industry is to prevent the high loss incurred during harvest, handling and transportation of the crops. The objective of this study was to investigate the overall nutritional implication of controlled storage of tomatoes using ozone on the ripening process and the basic nutritional components of tomatoes. This investigation was also designed to focus on the effect of different ozone doses on the basic components and properties (carotenoids, ascorbic acid, total antioxidant activity and soluble sugars content) of the quality and dynamic maturity of tomatoes.
Green tomatoes (Rio Grande) were treated in glass chambers with ozone enriched air [(air + 2, 7 and 21 mg O3/g tomato) and control (air only)] under humidity and temperature of 90-95% and 14-17 oC respectively. Tomatoes were sampled after 14 days of ozone treatment in the storage chamber and analyzed for different quality parameters (appearance, weight loss, Total Soluble Solids (TSS), titratable acidity, total ascorbic acid and carotene) of the ripening.
The variety Elegance tomatoes were selected and the fruits were graded by colour and subjected to treatment with ozone (in doses 0 (clean air), 0.25, 0.50, and1.00 mg O3/g tomatoes) during storage for 6 days under the same humidity and temperature conditions. The fruits were analysed for carotenoids, ascorbic acid content, total antioxidant activity and soluble sugars.Analysis of the fruits clearly showed that ozone significantly delayed the development of colour on the surface, particularly in the low doses, and caused black spots on the surface of the tomatoes, particularly in higher ozone doses. Ozone did not affect the ascorbic acid and titratable acidity content. However ozone did reduce the Total Soluble Solids (TSS) by about 10% at the lowest ozone dose. A high inhibition of accumulation of carotenoids, particularly at low dose, of the tomatoes (Rio Grande) was also observed.
Tomatoes (Elegance) under ozone treatments contained higher ß-carotene than those under the control treatment and lycopene content increased during storage in the red stage of tomato fruits. Ascorbic acid (AsA), dehydroascorbic acid (DHA) and the total of AsA and DHA concentrations, and ratios of redox (ASA/ (ASA + DHA) and DHA/AsA in pericarp and pulp of tomatoes tissue, did not show clear differences between the different treatments. The concentrations of the glucose and fructose increased in the tomatoes which were subjected to ozone treatments.
Results from this study show that controlled atmosphere storage of tomatoes using ozone is a viable technique which warrants further study. / Libyan government
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Eficácia de revestimentos a base de quitosana e óleos essenciais de mentha SSP. No controle de fungos patógenos pós-colheita em frutosGUERRA, Ingrid Conceição Dantas 17 June 2015 (has links)
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Previous issue date: 2015-06-17 / CETENE / Frutas são ricas em vitaminas, minerais, fibras e outros compostos que trazem benefícios à saúde. O conhecimento desses benefícios tem proporcionado aumento no consumo nos últimos anos, pois, além do interesse em fitoconstituintes os consumidores têm buscado produtos de elevada qualidade e seguros para o consumo. Devido à alta perecibilidade da matéria-prima e às falhas ocorridas nas diferentes fases da cadeia pós-colheita, grande parte dos vegetais produzidos no Brasil são desperdiçados. Dentre os diversos fatores envolvidos as doenças ocasionadas por fungos fitopatógenos se destacam. O controle de doenças fúngicas pós-colheita é comumente realizado através da aplicação de fungicidas, de elevado custo de produção e apresentados como ameaça à saúde pública e ao meio ambiente. Tendo em vista a problemática apresentada, no presente estudo foi avaliada a eficácia de revestimentos elaborados com quitosana (QUI) e óleos essenciais de Mentha piperita L. (MPOE) ou Mentha x villosa Huds (MVOE) como alternativa para o controle de infecções causadas pelos fungos Aspergillus niger, Botrytis cinerea, Penicillium expansum e Rhizopus stolonifer em tomates cereja e uvas de mesa durante o armazenamento em temperatura ambiente e em baixas temperaturas. A quitosana foi obtida da carapaça do camarão Litopenaus vannamei, em meio alcalino. Os óleos essenciais foram obtidos por arraste de vapor. Para o preparo do revestimento, o polímero de quitosana foi diluído em ácido acético sob agitação por 6 horas, seguido da adição do óleo e agitação por mais 18 horas em presença de glicerol como agente dispersante. As Concentrações Inibitórias Mínima da quitosana e de cada óleo foram determinadas por meio da macrodiluição em caldo. Os efeitos dos revestimentos sobre as características fúngicas (crescimento micelial radial e germinação espórica), físico-químicas (perda de peso, firmeza, cor, acidez e sólidos solúveis) e sensoriais (aceitação e intenção de compra) dos frutos durante a armazenagem também foram avaliados. A concentração inibitória mínima (CIM) de QUI contra todos os fungos-teste foi de 8 mg / mL, ao passo que a CIM para ambos MPOE e MVOE foi de 5 μL / mL. Combinações de QUI (8 e 4 mg/mL) e MPOE (QUI-MPOE) ou (QUI-MVOE) (5, 2,5 e 1,25 μL/mL) inibiu fortemente a germinação de esporos e o crescimento micelial dos fungos estudados. Os revestimentos compostos de QUI-MPOE ou QUI-MVOE retardaram o crescimento dos fungos causadores de mofos ensaiados em frutos artificialmente infectados durante a armazenagem em temperatura ambiente (12 dias) ou em baixa temperatura (24 dias). Os revestimentos ensaiados também preservaram a qualidade de frutos de tomate cereja e uvas de mesa durante a armazenagem, em termos de características físico-químicas e sensoriais. Nas uvas de mesa, houve uma melhoria nos valores de firmeza, cor L* e cor h* indicando frutos mais brilhosos e um possível retardo no desenvolvimento do "browning" das uvas revestidas com QUI-MPOE ou QUI-MVOE em relação aos frutos controle. Estes resultados indicam que os revestimentos que compreendem CHI-MPOE ou CHI-MVOE, apresentam-se como alternativa promissora para inibir a infecção de fungos pós-colheita em tomate cereja e uvas de mesa durante o armazenamento sem afetar a qualidade desses frutos. / Fruits are rich in vitamins, minerals, fiber and other compounds that provide health benefits. Knowledge of these benefits has provided an increase in vegetable consumption in recent years because in addition to the interest in phytochemicals that benefit the health and nutritional value, consumers have sought high quality products and safe for consumption. Due to the high perishability of the raw material and the failures occurred in different stages of post-harvest chain, most of the vegetables produced in Brazil are wasted. Among the many factors involved diseases caused by fungi pathogens in fruits stand out, they result in significant economic losses. Control of post-harvest fungal diseases commonly is achieved through the application of fungicides, increase the cost of production and presented to public health and the environment. In view of the problems presented, in the present study we evaluated the efficacy comprising shrimp chitosan (CHI) and Mentha piperita L. (MPEO) or Mentha x villosa Huds (MVEO) essential oils as an alternative for the control mold infections caused by Aspergillus niger, Botrytis cinerea, Penicillium expansum and Rhizopus stolonifer of cherry tomatoes and table grapes during storage at room temperature and low temperatures. Chitosan was obtained from the shell of the shrimp Litopenaeus vannamei in alkaline medium. The essential oils were obtained by vapor dragging. To prepare the coating, the polymer chitosan was diluted acetic acid with stirring for 6 hours, followed by addition of the oil and shaken for 18 more hours in the presence of glycerol as a dispersing agent. The Minimum Inhibitory Concentrations in chitosan and each oil were determined by the broth macrodilution. The effects of the coatings on the fungal characteristics (radial mycelial growth and esporic germination), physico-chemical (weight loss, firmness, color, acidity and soluble solids) and sensory (acceptance and purchase intention) of the fruit during storage were also evaluated. The minimum inhibitory concentration (MIC) of CHI against all the test fungi were 8 mg / mL, whereas the MIC for both MPOE and MVOE was 5 uL / mL. Combinations CHI (8 and 4 mg / mL) and MPOE (CHI-MPOE) or (CHI-MVOE) (5, 2.5 and 1.25 uL / mL) strongly inhibited spore germination and mycelial growth of of target fungi. The coatings comprising CHI-MPEO or CHI-MVEO delayed the growth of mold-causing fungi in artificially infected fruits during storage at either room (12 days) or low temperatures (24 days). The assayed coatings preserved the quality of cherry tomato fruits and table grapes during storage, in terms of physical, physicochemical and sensory attributes. In table grapes, there was an improvement in the firmness values, color L * and h * color indicating more glossy fruit and a possible delay in the development of "browning" of grapes coated with CHI-CHI-MPOE or MVOE compared to control fruits. These results indicate that coatings comprising CHI-MPEO or CHI-MVEO represent promising post-harvest treatments to inhibit common postharvest mold infections in cherry tomato fruits and in table grapes during storage without affecting the quality of these fruits.
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