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1	Effect of Hot Water Immersion Treatment (HWT) on the Quality of 'Keitt' Mangoes in Ghana Sebe, Akua Tiwaa 07 May 2016 (has links) Currently, Ghana does not use Hot Water Treatment (HWT) as a phytosanitary control measure for mangoes. The effect of HW on the quality of ‘Keitt’ mangoes in Ghana was evaluated. Mangoes were washed with chlorinated water or hot water treated at 47°C for 70 min and stored at 25°C for 8 days. There was no treatment*Storage effect (P> 0.05) on the variables studied. Mangoes TA decreased (P<= 0.05) and pH increased with storage time. HWT had no impact on mango quality but had 50% reduction in decay during storage. hot water treatment Ghana mango
2	Evaluation of hot water and menthyl jasmonate treatments for mitigation of chiling injary to improve 'hass' Avocado fruit skin colour Setagane, Lethabo January 2020 (has links) Thesis (M.Sc.(Agricultural Management )) -- University of Limpopo, 2020 / Avocado fruit ‘Hass’ harvested during early-season and exposed to temperature at 5.5°C for 28 d are susceptible to chilling injury (CI); and therefore, develop poor skin colour during ripening. In ‘Hass’ avocado fruit, skin colour change during ripening is used by European market to indicate fruit ripeness and softness. Therefore, the aim of this study was to evaluate the use of hot water (HW) and methyl jasmonate (MJ) as postharvest treatment dips to mitigate CI; and thereby, enhance ‘Hass’ avocado fruit peel colour during ripening. Fruit were harvested randomly from 5 selected trees treated alike during early season (April 2018); and thereafter, transported to the laboratory. At the laboratory, experiments of this study were divided into 2: experiment (1) fruit were dipped into HW (38, 42 and 46°C for 30, 25 and 20 min, respectively); and experiment (2) fruit were dipped into MJ (10 and 100 µmol/L for 2 min) treatments. In both experiments after these treatments, fruit were allowed to dry for 60 minutes at ambient (±25°C) temperature and untreated fruit were used as control. Thereafter, fruit were stored at commercial shipping temperature (5.5°C) for up to 28 d. After removal from cold storage, fruit were ripened at ambient temperature (±25°C) and evaluated every after 2 d for weight loss, firmness loss, objective colour parameters (lightness-L, chroma-C and hue angle-h), subjective colour (eye colour) and ripening percentage. However, chilling injury (CI) and electrolyte leakage (EL) were evaluated immediately after removal from cold storage. The results showed that HW significantly (P< 0.05) increased weight and firmness loss during ripening. Furthermore, HW reduced EL and external chilling injury (ECI) of ‘Hass’ avocado fruit during cold storage. In addition, the results showed that HW had significant effect (P< 0.05) on colour parameter L and eye colour rating, but did not affect (P> 0.05) C* and h. Avocado ‘Hass’ fruit subjected to HW at 42°C/25 and 46°C/20 min developed purple colour (eye colour rating 4.47 and 4.36, respectively) during ripening when compared with HW at 38°C/30 min and control fruit. Moreover, results showed that dipping fruit in 10 µmol/L had a significant effect (P< 0.05) on reducing weight loss during ripening. Methyl jasmonate (10 and 100 µmol/L) treatment reduced EL and alleviated external chilling injury (ECI) of ‘Hass’ fruit during cold storage. The results showed that MJ (10 and 100 µmol/L) treatments had significant effect (P< 0.05) on colour parameter L, h* and eye colour rating, but did not affect (P> 0.05) C*. Furthermore, ‘Hass’ fruit treated with 10 and 100 µmol/L MJ reached the purple skin colour (eye rating 5.39 and 5.19, respectively) during ripening. Fruit dipped in MJ (10 µmol/L) had low weight loss when compared with fruit treated with MJ (100 µmol/L). In conclusion, the results of this study indicated that HW (42°C/25 minutes) and MJ (10 µmol/L) effectively alleviated external chilling injury; and therefore, improved ‘Hass’ skin colour development during ripening / Agricultural Research Council-Institute (Agriseta) and University of Limpopo methyl jasmonate hot water treatment chilling injury skin colour ‘Hass’ avocado Avocado Hot water Salisbury treatment
3	Atividade antioxidante, compostos fenólicos totais e cor em abacate ‘hass’ submetido a diferentes tratamentos físicos Tremocoldi, Maria Augusta [UNESP] 03 March 2011 (has links) (PDF) Made available in DSpace on 2014-06-11T19:26:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-03-03Bitstream added on 2014-06-13T20:34:24Z : No. of bitstreams: 1 tremocoldi_ma_me_botfca.pdf: 616438 bytes, checksum: 67f1da03c193fb8aca4f0e4cbb1ebdac (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O presente trabalho teve por objetivo determinar a atividade antioxidante, compostos fenólicos totais e cor em abacate ‘Hass’ submetido ao tratamento térmico, radiação gama e ultravioleta. Após a colheita, os frutos foram selecionados para tornar o lote homogêneo. Foi realizada a caracterização do fruto verde e amadurecido quanto a acidez titulável, pH, umidade, teor de lipídios, cinzas (minerais), proteína (nitrogênio bruto), açúcar total e coloração. Foram realizados 3 experimentos com frutos recém colhidos. Experimento I: imersão dos frutos em água a 45ºC por 5, 10, 15 e 20 minutos; Experimento II: radiação gama nas doses 0,2; 0,4; 0,6 e 1,0kGy e Experimento III: radiação ultravioleta (UVC) por 5, 10, 15 e 20 minutos. Após os tratamentos, os frutos foram armazenados em temperatura ambiente (21ºC±1 e 70±5% de UR) e refrigerado (10ºC±1 e 90±5% de UR). Os frutos foram analisados quanto à capacidade antioxidante pelo método DPPH e compostos fenólicos totais aos 0, 3, 9 e 12 dias. A coloração foi avaliada aos 0, 3, 6, 9, 12 e 15 dias. Os resultados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey ao nível de 1% de probabilidade. Nas condições em que os experimentos foram realizados, pode-se concluir que os frutos do tratamento testemunha e mantidos sob refrigeração apresentaram maior capacidade antioxidante e teor de compostos fenólicos totais ao longo do período de armazenamento; o tratamento térmico por 5 e 10 minutos foi efetivo na manutenção da capacidade antioxidante e dos compostos fenólicos; a dose de 0,6kGy não foi efetiva na manutenção da capacidade antioxidante; a radiação ultravioleta (UV-C) não manteve a capacidade antioxidante dos frutos, no entanto ocasionou aumento na quantidade de compostos fenólicos; o tratamento térmico e a radiação ultravioleta não afetaram a coloração da polpa / This study aimed to determine the antioxidant activity, total phenolic compounds and color in avocado 'Hass' submitted to heat treatment, gamma and ultraviolet radiation. After harvest, fruits were selected to make the homogeneous portion. The characterization was performed of the green fruit and mature as acidity, pH, moisture, lipids, ash (minerals), protein (nitrogen gross), total sugar and coloring. 3 experiments were performed with freshly harvested fruits. Experiment I: immersion of fruits in water at 45 ° C for 5, 10, 15 and 20 minutes; Experiment II: gamma radiation doses 0.2, 0.4, 0.6 and 1.0 kGy and Experiment III: ultraviolet radiation (UV-C) for 5, 10, 15 and 20 minutes. After treatments, fruits were stored at room temperature (21±1ºC and 70±5% HR) and refrigeration (10ºC±1 and 90±5% HR). The fruits were analyzed for their antioxidant capacity by DPPH method and phenolic compounds at 0, 3, 9 and 12 days. The color was measured at 0, 3, 6, 9, 12 and 15 days. Data were subjected to analysis of variance and mean comparison using Tukey’s test at 1% probability. In conditions where the experiments were performed, one can conclude that the fruits of control treatment and kept under refrigeration had higher antioxidant capacity and content of phenolic compounds during the storage period, the heat treatment for 5 and 10 minutes was effective the maintenance of antioxidant capacity and phenolic compounds, the dose of 0.6 kGy was not effective in maintenance the antioxidant capacity, ultraviolet radiation (UV-C) did not maintain the antioxidant capacity of fruits, however caused an increase in the content of phenolic compounds, heat treatment and ultraviolet radiation did not affect the pulp color Abacate - efeito da radiação Radiação ultravioleta Persea americana Mill Hot water treatment Gamma radiation Ultraviolet radiation (UV-C)
4	Atividade antioxidante, compostos fenólicos totais e cor em abacate 'hass' submetido a diferentes tratamentos físicos / Tremocoldi, Maria Augusta, 1983- January 2011 (has links) Orientador: Rogério Lopes Vieites / Banca: Erica Regina Daiuto / Banca: Severino Matias de Alencar / Resumo: O presente trabalho teve por objetivo determinar a atividade antioxidante, compostos fenólicos totais e cor em abacate 'Hass' submetido ao tratamento térmico, radiação gama e ultravioleta. Após a colheita, os frutos foram selecionados para tornar o lote homogêneo. Foi realizada a caracterização do fruto verde e amadurecido quanto a acidez titulável, pH, umidade, teor de lipídios, cinzas (minerais), proteína (nitrogênio bruto), açúcar total e coloração. Foram realizados 3 experimentos com frutos recém colhidos. Experimento I: imersão dos frutos em água a 45ºC por 5, 10, 15 e 20 minutos; Experimento II: radiação gama nas doses 0,2; 0,4; 0,6 e 1,0kGy e Experimento III: radiação ultravioleta (UVC) por 5, 10, 15 e 20 minutos. Após os tratamentos, os frutos foram armazenados em temperatura ambiente (21ºC±1 e 70±5% de UR) e refrigerado (10ºC±1 e 90±5% de UR). Os frutos foram analisados quanto à capacidade antioxidante pelo método DPPH e compostos fenólicos totais aos 0, 3, 9 e 12 dias. A coloração foi avaliada aos 0, 3, 6, 9, 12 e 15 dias. Os resultados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey ao nível de 1% de probabilidade. Nas condições em que os experimentos foram realizados, pode-se concluir que os frutos do tratamento testemunha e mantidos sob refrigeração apresentaram maior capacidade antioxidante e teor de compostos fenólicos totais ao longo do período de armazenamento; o tratamento térmico por 5 e 10 minutos foi efetivo na manutenção da capacidade antioxidante e dos compostos fenólicos; a dose de 0,6kGy não foi efetiva na manutenção da capacidade antioxidante; a radiação ultravioleta (UV-C) não manteve a capacidade antioxidante dos frutos, no entanto ocasionou aumento na quantidade de compostos fenólicos; o tratamento térmico e a radiação ultravioleta não afetaram a coloração da polpa / Abstract: This study aimed to determine the antioxidant activity, total phenolic compounds and color in avocado 'Hass' submitted to heat treatment, gamma and ultraviolet radiation. After harvest, fruits were selected to make the homogeneous portion. The characterization was performed of the green fruit and mature as acidity, pH, moisture, lipids, ash (minerals), protein (nitrogen gross), total sugar and coloring. 3 experiments were performed with freshly harvested fruits. Experiment I: immersion of fruits in water at 45 ° C for 5, 10, 15 and 20 minutes; Experiment II: gamma radiation doses 0.2, 0.4, 0.6 and 1.0 kGy and Experiment III: ultraviolet radiation (UV-C) for 5, 10, 15 and 20 minutes. After treatments, fruits were stored at room temperature (21±1ºC and 70±5% HR) and refrigeration (10ºC±1 and 90±5% HR). The fruits were analyzed for their antioxidant capacity by DPPH method and phenolic compounds at 0, 3, 9 and 12 days. The color was measured at 0, 3, 6, 9, 12 and 15 days. Data were subjected to analysis of variance and mean comparison using Tukey's test at 1% probability. In conditions where the experiments were performed, one can conclude that the fruits of control treatment and kept under refrigeration had higher antioxidant capacity and content of phenolic compounds during the storage period, the heat treatment for 5 and 10 minutes was effective the maintenance of antioxidant capacity and phenolic compounds, the dose of 0.6 kGy was not effective in maintenance the antioxidant capacity, ultraviolet radiation (UV-C) did not maintain the antioxidant capacity of fruits, however caused an increase in the content of phenolic compounds, heat treatment and ultraviolet radiation did not affect the pulp color / Mestre Abacate - efeito da radiação. Radiação ultravioleta. Persea americana Mill. eng Hot water treatment. eng Gamma radiation. eng Ultraviolet radiation (UV-C) eng
5	Mekanisk uppgrävning: ett effektivt verktyg mot den invasiva främmande arten gul skunkkalla (Lysichiton americanus) : En utredning av behandlingsmetoder Kekäle, Oscar January 2023 (has links) Den biologiska mångfalden minskar globalt och ett av de största hoten utgörs av invasiva främmande arter. Natura-2000 området Fylleån, Halland, huserar en av de största svenska populationerna av gul skunkkalla (Lysichiton americanus). Arten utgör ett hot mot de naturvärden som finns i Fylleån och är subjekt för extensiva behandlingsarbeten i området för att motarbeta växtens effekt på ekosystemet. Det finns i dagsläget ingen evidens för att behandlingsmetoderna som presenteras av Naturvårdsverket och Havs- och vattenmyndighetens metodkatalog har effektivitet i svenska vattendrag. Målet med min studie är att undersöka effektiviteten av mekanisk uppgrävning samt ytlig hetvattensbehandling som behandlingsmetoder för gul skunkkalla. Jag undersöker även lämpligheten för användandet av övriga metoder presenterade av metodkatalogen och metoderna hetvattensbehandling och fröställningsborttagning som inte listats i metodkatalogen men som testas av myndigheter i viss utsträckning. Den första delen av studien genomförs som jämförelsestudie mellan områden som behandlats i olika grad med mekanisk grävning och hetvattenbehandling för att bestämma metodernas effektivitet. Den andra delen av min studie var att genom en litteraturgenomgång med metodkatalogen som utgångspunkt avgöra lämpligheten på och reflektera över metoderna samt reflektera över metodernas lämplighet att användas civilt. Min slutsats är att mekanisk grävning ger minskande populationer och signifikanta skillnader i individantal, förutsatt att behandlingen utförs rätt och konsekvent. Jag resonerar att andra behandlingsmetoder kan påverka mer organismer än vad man avsett och att de därför är olämpliga att bruka i Fylleån. Jag diskuterar vad jag anser är rimligt idéellt arbete i nuläget samt framtida potential och behovet av information i rätt kanaler. / Biodiversity is decreasing globally and one of the biggest threats is invasive alien species. The Natura-2000 area Fylleån, Halland, houses one of the largest Swedish populations of the American skunk cabbage (Lysichiton americanus). The species poses a threat to the natural values found in Fylleån and is subjected to extensive treatment to counteract the plant's effect on the ecosystem. There is currently no evidence for the effectiveness of the treatment methods presented by Naturvårdsverket and Havs- och vattenmyndighetens method catalog in Swedish watercourses. The goal of my study is to investigate the effectiveness of mechanical excavation and superficial hot water treatment as treatment methods for American skunk cabbage, along with hot water treatment and seed stand removal which are not listed in the method catalog but are tested by authorities to a certain extent. Through a comparative study between areas treated to varying degrees with mechanical digging and hot water treatment, I determine the effectiveness of the methods. The second part of my study was to try to determine the suitability of and reflect on the methods, as well as reflect on the suitability of the methods for civilian use through a literature review using the method catalog as a starting point. My conclusion is that mechanical digging produces declining populations and significant differences in found individuals, provided the treatment is carried out correctly and consistently. I reason that other treatment methods can affect more organisms than intended, and that they are therefore unsuitable for use in Fylleån. Invasive species Yellow skunk cabbage American skunk cabbage Lysichiton americanus Ecology Botany IAS Halland Plants Nature Methodolgy Mechanical digging hot water treatment heatweed glyfosate climate Lysichiton Araceae inventory species description statistical analysis litterature review watercourse invasive plants Sustainability Biology Natural sciences Halmstad university Invasiva främmande arter Gul skunkkalla Lysichiton americanus Ekologi Botanik heatweed Araceae IAS Halland Växter Natur Behandlingsmetoder Mekanisk uppgrävning hetvattenbehandling glyfosat klimat kalleväxter inventering artbeskrivning statistisk analys metodkatalogen litteraturgenomgång vattendrag invasiva växter globala målen hållbarhet Biologi Naturvetenskap Högskolan i Halmstad Natural Sciences Naturvetenskap Biological Sciences Biologiska vetenskaper Ecology Ekologi Botany Botanik

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