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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.
91

Métodos de conservação de framboesa in natura / Conservation methods for fresh raspberry fruit

Tezotto-Uliana, Jaqueline Visioni 31 August 2012 (has links)
O desenvolvimento de métodos para a conservação pós-colheita de framboesa in natura é de grande importância para a expansão da cultura no país, considerando que o principal entrave deste fruto é o curto período de comercialização. O presente trabalho teve como objetivo avaliar o efeito da aplicação de técnicas pós-colheita na conservação da qualidade de framboesa in natura, através do uso do armazenamento refrigerado, atmosfera modificada, aplicação pós-colheita do 1-metilciclopropeno (1-MCP) e aplicação pré e póscolheita de quitosana. Para isso, foram realizados seis experimentos. No primeiro, avaliou-se a melhor temperatura para a refrigeração dos frutos, sendo estes armazenados a 0, 5, 10 ou 15ºC e 90±5% de UR, por 12 dias (a melhor temperatura foi usada nos experimentos seguintes). O segundo experimento constituiu-se da utilização da atmosfera modificada passiva, armazenando os frutos, por 15 dias, em cloreto de polivinila (PVC - 15 m), polietileno de baixa densidade (PEBD - 10 e 20 m), polietileno de alta densidade (PEAD), polipropileno (PP - 10 m), politereftalato de etileno (PET) não perfurados e perfurados (sem modificação de atmosfera). No terceiro experimento, os frutos foram expostos ao 1-MCP a 0, 100, 500, 1000 e 2000 nL L-1, por 12 horas e, então, armazenados por 12 dias. No quarto experimento foi avaliado o comportamento dos frutos em resposta a aplicação pós-colheita de diferentes concentrações de quitosana. Os frutos foram imersos em soluções a 0, 0,5, 1 e 2%, por cinco minutos e, então, armazenados por 15 dias. No quinto experimento estudou-se a aplicação pré-colheita de quitosana, sendo toda a planta aspergida semanalmente, durante três semanas, nas mesmas concentrações do experimento anterior. Depois de colhidos, os frutos foram armazenados por 12 dias. No sexto experimento foi testada a associação das melhores técnicas pós-colheita estudadas nos experimentos anteriores, sendo que a sua ordem de aplicação resultou em diferentes tratamentos. Os frutos foram armazenados por 20 dias. A temperatura de 0ºC foi a mais indicada para a conservação e ampliação da vida útil de framboesas. A modificação da atmosfera resultante do uso do PEBD 10 m trouxe os melhores resultados na pós-colheita desse fruto. A aplicação do 1-MCP aliada à refrigeração não aumentou o período de comercialização da framboesa, mas manteve os frutos tratados com qualidade superior, sendo concentrações entre 1000 a 2000 nL L-1 as mais indicadas. O uso da quitosana aliada à refrigeração foi eficiente na manutenção da qualidade da framboesa, no entanto, apenas a aplicação na pós-colheita ampliou o período de comercialização. As melhores concentrações para a pré e pós-colheita foram 2 e 1%, respectivamente. A aplicação conjunta da refrigeração, filme plástico, 1-MCP e quitosana em pós-colheita amplia a vida útil do fruto, não importando a ordem de aplicação dos tratamentos. / The development of methods for maintaining fresh raspberry quality has great importance for the berry crop growth in Brazil, considering that the main difficulty has been the short shelf-life of this fruit. The aim of this study was to evaluate the effect of postharvest techniques in quality conservation of fresh raspberry, using cold storage, modified atmosphere, 1-methylcyclopropene (1-MCP) application and chitosan application in pre and postharvest. For this purpose six experiments were performed. At first, fruits were stored at 0, 5, 10 or 15°C and 90±5% RH during 12 days, for evaluation of best storage temperature (that was used in all following experiments). The second experiment was the use of modified atmosphere, storing the raspberries for 15 days in polyvinyl chloride (PVC - 15 m), low density polyethylene (LDPE - 10 and 20 m), high density polyethylene (HDPE), polypropylene (PP - 10 m), polyethylene terephthalate (PET) without and with holes (this last one being unmodified atmosphere). For the third experiment, the fruits were exposed to 1-MCP at 0, 100, 500, 1000 and 2000 nL L-1 for 12 hours, and then stored during 12 days. The fourth experiment assessed the fruit behavior in response to postharvest application of different chitosan concentrations. The fruits were immersed in solutions of 0, 0.5, 1 and 2% during five minutes and then stored for 15 days. The pre-harvest chitosan application was studied in the fifth experiment, where whole plants were treated with three weekly spray applications, at the same concentrations of the previous experiment, and then the fruit were stored for 12 days. In the sixth experiment, the association of the best treatments from the previous experiments was evaluated. The application order of the techniques led to different treatments, and fruit were stored for 20 days. The 0ºC temperature is the most recommended for the preservation and extension of raspberry shelf-life. The use of LDPE - 10 m provides the best modified atmosphere treatment for raspberry. The 1-MCP application does not increase the raspberry marketing period, but it keeps the treated fruits with superior quality, and the concentrations ranging from 1000 to 2000 nL L-1 are the most indicated. The chitosan is efficient in maintaining the raspberry quality, however, only the postharvest application extends the shelf-life. The best concentration for pre and postharvest are 2 and 1%, respectively. The combined application of cold storage, plastic film, 1-MCP and postharvest chitosan extends the fruit shelf-life, independent of the order of the treatments.
92

Effect of cold storage temperature and silicon dips on physico-chemical properties of a new mandarin selection "M37" fruit

Shibambu, Rhulani Beauty January 2018 (has links)
Thesis (MSc. Agriculture (Horticulture)) -- University of Limpopo, 2018 / Newly developed mandarin selection ―M37‖ has the potential to become a future export soft citrus cultivar. However, the selection is highly susceptible to chilling injury, which normally reduces post-storage quality and marketability of citrus fruit. Silicon (Si), applied at post-harvest as potassium silicate (K2SiO3), has potential to mitigate against chilling injury. So far, the effect of Si on ―M37‖ mandarin chilling susceptibility is unknown. Therefore, the aim of the study was to investigate the effect of cold storage temperature and postharvest potassium silicate dips on the chilling susceptibility and physico-chemical properties of new mandarin selection ―M37‖ fruit. The experiment was carried out in a factorial, arranged in a completely randomised design (CRD) with three replicates. Treatment factors were: 2 x cold storage temperature (-0.6±1 and 4.5 ±1°C) and 4 x potassium silicate concentration (0, 50, 100 and 150 mL L-1 K2SiO3). Fruit were dipped in different potassium silicate solutions (0, 50, 100 and 150 mL L-1) for 30 minutes, air dried, waxed; and thereafter, stored for 28 days at -0.6 and 4.5°C with 85-90% relative humidity. After withdrawal from cold storage, fruit were held at ambient temperature (±23°C) for 7 days (shelf-life); during shelf-life fruit were evaluated for chilling injury, physical properties (weight loss and firmness loss) and biochemical properties (electrolyte leakage, total soluble acids (TSS), titratable acids (TA) and TSS: TA ratio). The results showed that fruit were highly susceptible to chilling injury after storage at 0.6°C when compared with 4.5°C. However, treating fruit with postharvest potassium silicate dips improved their chilling susceptibility, especially with 50 and 100 mL L-1 K2SiO3 concentrations. Electrolyte leakage was lower for fruit treated with K2SiO3 compared to the control across all the storage temperatures. Although, ―M37‖ fruit stored at 4.5°C showed higher weight loss, firmness loss, TSS and TSS: TA ratio when compared with -0.6°C storage. Fruit firmness increased with the increase in potassium silicate concentrations during storage at -0.6 and 4.5°C; with the highest firmness loss occurring on fruit treated with 150 mL L-1 than control. Similarly, TSS increased concomitant with K2SiO3 concentration. Although, TA decreased with increasing K2SiO3 concentrations for fruit stored at 4.5°C; resulting in higher TSS: TA ratio. In conclusion, postharvest silicon dips effectively improved the storability of ―M37‖ mandarin fruit, preserved quality and extended the cold storage period. xi Keywords: Biochemical properties; Chilling injury; Firmness loss; Potassium silicate dips; Weight loss / Agricultural Research Council (ARC-LNR) and National Research Fund (NRF)
93

Ultra-low temperature shipping and cold chain management of 'fuerte' avocados (Persea americana Mill.) grown in the KwaZulu-Natal Midlands.

Lutge, Andre. 15 November 2013 (has links)
‘Fuerte’ makes up 25% of the avocados exported from South Africa to European markets and requires shipping periods of up to 28 days and a correctly managed cold chain. A temperature of 5.5°C and expensive CA and 1-MCP treatments are currently used to delay ripening over this lengthy cold chain; however, fruit still appear on the European market showing signs of softening and physiological disorders. Increased competition on the global market and the disadvantage of a particularly long distance to the European market has challenged the South African export industry. These challenges have necessitated improved road and sea transport logistics, co-ordination with producing countries which supply fruit to European markets over similar periods as South Africa, and research into ultra-low temperature storage to possibly enable future access to new lucrative markets in the USA, China and Japan. It is also known that there are various ‘weak links’ in this cold chain and that cold chain breaks are detrimental to fruit quality, but further research into the negative effects of these cold chain breaks at ultra-low temperatures was needed. Thus, the objective of the study was to determine the potential for shipping ‘Fuerte’ avocados at temperatures of 2°C as well as determining the effects of cold chain breaks on fruit quality, throughout the growing season and possibly for an extended period of 56 days. ‘Fuerte’ avocados were harvested at three different maturity stages reflecting early-, mid- and late-season fruit, with moisture contents of 74%, 68% and 63%, respectively. Fruit were stored at 2°C or 5.5°C, treated with 1-MCP and waxed. Additionally cold chain breaks (24 hour delay and break at 14 days) were implemented. Fruit softening, mass loss, days-to-ripening, external and internal quality as well as antioxidant levels and total sugar levels were determined. The first aim was to determine whether a lower than currently used storage temperature could be a successful alternative to 1-MCP use. A storage temperature of 2°C provided good internal quality as well as reduced mass loss and fruit softening, which is related to the slightly reduced use of C7 sugars at 2°C compared with 5.5°C. Although the overall occurrence of external chilling injury was relatively low, 2°C storage caused a notably higher occurrence of external chilling injury than 5.5°C storage, particularly early in the season, but extended the days-to-ripening. Unfortunately, no correlation between the anti-oxidants in the exocarp and external damage was found. Waxing significantly reduced the external damage on fruit stored at 2°C, so much so, that the treatment combinations of ‘2°C, no 1-MCP, waxed’ showed no external chilling injury throughout the season. Further, waxing fruit at 2°C could eliminate the need for 1-MCP, delivering a product of the required shelf-life and quality. Best results were achieved for mid-season fruit stored at 2°C. Late-season fruit would potentially be the most profitable to store at this low temperature, however, body rots (anthracnose and stem-end rot) were more common in the late-season. Storage at 2°C can therefore maintain the internal quality over a storage period of 28 days and be a potential alternative to 1-MCP use as the season progresses. The effect of cold chain breaks on fruit quality was then investigated and showed that both a delay and a break in the cold chain increased mass loss and fruit softening, reduced days-to-ripening and increased external chilling injury, especially early in the season. Water loss was the main contributor to the decreased fruit quality which resulted from the delay in cooling, increasing external damage significantly, particularly early in the season. The break at 14 days had a marked effect on physiological activity of fruit during storage, seen mainly in the increased metabolic activity, resulting in increased fruit softening and water loss during storage and a decrease in C7 sugars and thus shelf-life, particularly for fruit stored at 5.5°C. Importantly, 1-MCP use and storage at 2°C reduced the effects of cold chain breaks with respect to fruit softening, however, lowering the storage temperature had a greater negating effect than 1-MCP and could be a successful alternative to the use of 1-MCP. The internal quality throughout the experiment was very good, with few internal disorders and no significant treatment effects on internal quality and C7 sugar concentrations. Overall, a break in the cold chain, before and during cold storage, resulted in a marked reduction in fruit quality. The storage temperature of 5.5°C should not be used for a 56 day storage period as it resulted in significant fruit softening during storage, even when 1-MCP was used, and resulted in significantly more external chilling injury in the mid- and late-season than at 2°C. Storage of 1-MCP treated, waxed fruit at 2°C, resulted in the best shelf-life and fruit quality, particularly mid-season fruit which had negligible external chilling injury and 100% sound fruit. Early-season fruit suffered significant external chilling injury at 2°C and late-season fruit had the highest body-rots and internal disorders at this storage temperature. Although mid-season fruit could be successfully stored at 2°C for 56 days, the use of a 56 day storage period is not recommended as a practical storage period, due to the high risk of external damage, particularly if maturity levels are not optimum and trees and fruit are not of the highest quality. Overall this thesis has shown that 1-MCP treatment can play an important role early in the season when fruit are susceptible to external damage, however, storage at 2°C results in good quality fruit and, when used in conjunction with waxing, appears to be a viable alternative to the use of 1-MCP, particularly later in the season. Further, the negative effects of cold chain breaks on fruit quality have been demonstrated and, importantly, the storage temperature of 2°C negates the fruit softening effects of these breaks, even if 1-MCP is not used. / Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.
94

Effect of methyl jasmonate and salicyclic acid on chilling injury of 'eureka' lemons.

Siboza, Xolani Irvin. January 2010 (has links)
South Africa is the second largest exporter of citrus fruit in the world. There has recently emerged a strong demand for lemons in the world market due to their nutritional value, culinary and non-culinary uses. During exportation, fruit are subjected to low temperature (-0.5°C) for varying periods of time as an obligatory quarantine treatment. However, lemons are sensitive to low temperatures and easily develop chilling injury during this obligatory quarantine treatment. This has become a major limitation to the expansion of South Africa’s lemon industry. Postharvest treatments with methyl jasmonate (MJ) and / or salicylic acid (SA) have been successfully used in horticultural crops to reduce chilling injury. A similar treatment was applied to ‘Eureka’ lemons. During the 2008 harvest season, postharvest fruit were either dipped in 10 or 50 μM MJ or 2 or 2.5 mM SA solutions. A control or no dip treatment was also applied. Three replicates of 15 fruits per treatment were used. During the 2009 harvest season the following postharvest treatments were applied as dips: 10 μM MJ, 2 mM SA, 10 μM MJ & 2 mM SA, 1 μM MJ & 0.2 mM SA, or 0.1 μM MJ & 0.02 mM SA solutions. A control or no dip treatment was also applied. Three replicates of 15 fruits per treatment were used. Subsequently fruit were stored at -0.5ºC for 0, 7, 14, 21, 28, 35, and 42 days, before being transferred to room temperature (25°C) for 7 days where after chilling injury was rated. Treatments with 10 μM MJ and / or 2 mM SA reduced chilling injury symptoms in lemons harvested during the 2009 season. Although no visual symptoms of chilling injury were observed during the 2008 harvest season, treatments with 10 μM MJ and / or 2 mM SA reduced fruit mass loss, delayed the occurrence of stress symptoms such as lipid peroxidation and suppressed accumulation of ROS in the rind. Treatments with 10 μM MJ and / or 2 mM SA were more effective in inducing antioxidant capacity and other defence compounds such as phenolics, ascorbic acid, carbohydrates and chilling injury responses such as accumulation of proline in the rind. This may have increased the chilling tolerance of fruit during the cold storage. Therefore, this study revealed that MJ and SA have the potential to reduce and delay symptoms of chilling injury in lemons. This lead to the suggestion that both, MJ and SA dips should be further tested as treatments to mitigate chilling injury in lemons. Future studies should focus more on preventing the injury itself or preventing the primary event of chilling injury. This could probably reduce the chances of secondary events to take place. / Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.
95

Root freezing tolerance and storability of Scots pine and Norway spruce seedlings /

Stattin, Eva, January 1900 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 4 uppsatser.
96

Cold storage of Leucospermum cutflowers and Leucadendron greens

Graham, Shelly 12 1900 (has links)
Thesis (MScAgric)--University of Stellenbosch, 2005. / ENGLISH ABSTRACT: Quality of certain Leucospermum and Leucadendron cultivars after approximately 21 days shipping has been reported to be substandard due to ‘drying out’ of leaves and, in the case of Leucadendrons, involucral leaves. The nature of the symptoms of this ‘drying out’ and the conditions under which they form, viz. long exposures to low temperatures, has led us to hypothesize that these are symptoms of chilling injury (CI). Chilling injury, as far as we are aware, has not been documented on Leucospermums or Leucadendrons. Typical CI symptomology is discussed and shown for Leucospermum ‘Gold Dust’, ‘High Gold’ and ‘Succession’ and for Leucadendron ‘Chameleon’, ‘Laurel Yellow’ and ‘Safari Sunset’. The nature of CI symptoms for Leucospermums and Leucadendrons was generally membranous breakdown that manifested in some cases as a ‘water soaked’ appearance which, at a more advanced stage, was generally visible as ‘dried out’ patches on the leaves. In the case of the Leucadendrons CI was also visible on the immature involucral leaves which are more sensitive to chilling conditions than mature leaves. Dark discoloration of especially immature involucral leaves is also a symptom of CI. As water uptake of shoots with chilling injury is hindered the styles of the Leucospermums wilt. As can be expected, the lower the temperature below the threshold temperature and the longer the exposure the more severe the symptoms. CI was recorded on cut flower shoots of Leucospermum ‘Gold Dust’, ‘High Gold’, ‘Rigoletto’, ‘Succession’ and ‘Vlam’ after 21 and 24 days storage at 1ºC. After 24 days storage the chilling injury was more severe than after 21 days storage in most cases. Each cultivar was pulsed with 5 ml per stem of a 2% (w/v) sugar solution of either lactulose, sucrose, glucose, fructose or mannose before storage. After storage, CI was recorded on day 0, 3, 7 and 10 of the vase phase. Of the cultivars tested ‘Vlam’ and especially ‘Rigoletto’ were more prone to chilling injury development. ‘High Gold’ and ‘Vlam’ shoots were pulsed with 0 (control), 1.5, 3 or 4% (w/v) solutions of either mannose or fructose. The best control of CI for both cultivars was achieved with 1.5% (w/v) solution. Lower concentrations of mannose and fructose were tested on ‘High Gold’ shoots, with a 1% (w/v) solution giving the best control for both. At high concentrations signs of toxicity became evident directly after pulsing. ‘High Gold’ shoots were pulsed with 1% (w/v) solutions of mannose and fructose and sugar analyses were performed on shoots at different stages of storage and after 10 days in the vase. A slight increase in mannose and fructose was detectable in the stems of the shoots directly after pulsing but not in the leaves or the inflorescences. This is due to the low concentrations being used. The levels of all the carbohydrates decreased during the 21 days storage and more so during the vase phase of the flowering shoots. The fact that such low concentrations were effective in controlling chilling injury suggests that the sugars may have an effect other than on the osmotic potential. Cut ‘flower’ shoots of Leucadendron ‘Chameleon’, ‘Laurel Yellow’ and ‘Safari Sunset’ were stored for 14, 21 and 28 days, at 1º, 3º and 5ºC and CI development recorded during the subsequent 10 day vase phase. ‘Laurel Yellow’ and ‘Safari Sunset’ showed signs of chilling injury on the leaves after 28 days storage at 3ºC or lower and ‘Safari Sunset’ stored for 21 days developed chilling injury during the vase phase. Immature involucral leaves were more sensitive to chilling injury than leaves. CI increased with longer exposure times and lower storage temperatures for all three cultivars evaluated. ‘Chameleon’ was the most chilling tolerant of the cultivars up to 21 days. At 5ºC chilling injury was low irrespective of cold storage duration but longer exposures to 1º and 3ºC resulted in increased chilling injury development during the vase phase. All three cultivars were pulsed with 5 ml per stem of a 1% (w/v) solution of lactulose, sucrose, glucose, fructose or mannose and stored for 14, 21 and 28 days at 1ºC. The sugars reduced chilling injury on the leaves for ‘Safari Sunset’ when stored for 28 days and, to a lesser extent, in ‘Chameleon’. The sugars failed to reduce chilling injury of the involucral leaves of ‘Chameleon’ and ‘Laurel Yellow’ whereas there was some control especially after 28 days for ‘Safari Sunset’. In some cases the sugar pulse exacerbated chilling injury. Chilling injury generally increased rapidly after storage during the first three days in the vase and then at a lower rate for the next seven days. Leucadendron ‘Chameleon’, ‘Laurel Yellow’ and ‘Safari Sunset’ ‘cut flower’ shoots were pulsed with a 1% (w/v) glucose solution. Expressed on a dry weight basis, an increase in glucose concentration was not detected. The reduction in chilling injury of leaves by a sugar pulse is speculated, as for the Leucospermums, to be as a result of their presence in the apoplast and not the symplast and that their presence there protects the membranes against chilling conditions in some way. / AFRIKAANSE OPSOMMING: Die kwaliteit van sekere Leucospermum en Leucadendron kultivars na ongeveer 21 dae verskeping is waargeneem as substandaard as gevolg van die uitdroog van blare en, in die geval van Leucadendrons, die ‘involucral’ blare. Die aard van die simptome van hierdie uitdroging en die toestande waaronder dit plaasvind nl. lang periodes van blootstelling aan lae temperature, het ons tot die hipotese gebring dat hierdie simptome van koueskade is. Sover as wat ons bewus is, is koueskade nog nie gedokumenteer op Leucospermums of Leucadendrons nie. Tipiese koueskade simptomologie word bespreek en gewys vir Leucospermum ‘Gold Dust’, ‘High Gold’ en ‘Succession’ en vir Leucadendron ‘Chameleon’, ‘Laurel Yellow’ en ‘Safari Sunset’. Die koueskade simptome vir Leucospermums en Leucadendrons was oor die algemeen membraan afbraak wat ‘n water deurdrenkte voorkoms tot gevolg gehad het wat in ‘n meer gevorderde stadium sigbaar was as uitgedroogde kolle op die blare. In die geval van Leucadendrons was koueskade ook sigbaar op die onvolwasse ‘involucral’ blare wat meer sensitief is vir koue toestande as volwasse blare. Donker verkleuring van veral onvolwasse ‘involucral’ blare is ook ‘n simptoom van koueskade. Aangesien wateropname van stele met koueskade verhinder word, verwelk die ‘styles’ van die Leucospermums. Soos verwag kan word hoe laer die temperature onder die drempel temperatuur en hoe langer die blootstelling, hoe meer ernstig die simptome. Koueskade is aangeteken op gesnyde blomstele van Leucospermum ‘Gold Dust’, ‘High Gold’, ‘Rigoletto’, ‘Succession’ en ‘Vlam’ na 21 en 24 dae opberging by 1°C. Na 24 dae opberging was die koueskade meer ernstig as na 21 dae opberging in meeste gevalle. Elke kultivar het 5ml per steel van ‘n 2% (g/v) suiker oplossing van laktolose, sucrose, glucose, fruktose of mannose voor opberging opgeneem. Na opberging is koueskade aangeteken op dag 0, 3, 7 en 10. Van die kultivars wat getoets is, was ‘Vlam’ en veral ‘Rigoletto’ meer geneig tot koueskade ontwikkeling. ‘High Gold’ en ‘Vlam’ stele is geplaas in oplossings van 0 (kontrole), 1.5, 3 of 4 % (g/v) oplossings van mannose of fruktose. Die beste beheer van koueskade vir beide kultivars is deur die 1.5 (g/v) oplossing behaal. Laer konsentrasies van mannose en fruktose is getoets op ‘High Gold’ stele met ‘n 1% (g/v) mannose oplossing wat die beste beheer gegee het. Met hoë konsentrasies het tekens van toksisiteit sigbaar geword direk na opneem van die oplossing. ‘High Gold’ stele is geplaas in 1% (g/v) oplossings van mannose of fruktose en suiker analises is uitgevoer op stele by verskillende stadiums van opberging en na 10 dae in die vaas. ‘n Effense toename in mannose en fruktose is waargeneem in die stele van die blomme direk na opname van die oplossing, maar nie in die blare of die blomme nie. Dit is as gevolg van die lae konsentrasies wat gebruik is. Die vlakke van al die koolhidrate het afgeneem gedurende die 21 dae opberging en nog meer so gedurende die vaas periode van die blommende stele. Die feit dat sulke lae konsentrasies effektief is in die beheer van koueskade dui daarop dat die suikers ‘n effek het anders as op die osmotiese potensiaal. Snyblomme van Leucadendron ‘Chameleon’, ‘Laurel Yellow’ en ‘Safari Sunset’ is opgeberg vir 14, 21 en 28 dae, by 1º, 3º en 5°C en koueskade ontwikkeling is aangeteken gedurende die opvolgende 10 dae vaas periode. ‘Laurel Yellow’ en ‘Safari Sunset’ het tekens gewys van koueskade op die blare na 28 dae opberging by 3°C of laer en ‘Safari Sunset’ opgeberg vir 21 dae het koueskade ontwikkel gedurende die vaas periode. Onvolwasse ‘involucral’ blare was meer sensitief vir koueskade as die blare. Koueskade het toegeneem met langer blootstellingstye en laer opbergins temperature vir al drie kultivars geëvalueer. ‘Chameleon’ was die mees koueverdraagsaam van die drie kultivars tot op 21 dae. By 5°C was laag ongeag van die koue opberging tydperk, maar langer blootstellings aan 1º en 3°C het gelei tot toename in koueskade ontwikkeling gedurende die vaas periode. Al drie kultivars is voorsien met 5ml per steel van ‘n 1% (g/v) oplossing van lactulose, sucrose, glucose, fruktose of mannose en opgeberg vir 14, 21 en 28 dae by 1°C. Die suikers het koueskade verminder op die blare van ‘Safari Sunset’ wanneer opgeberg vir 28 dae en, tot ‘n mindere mate, in ‘Chameleon’. Die suikers het egter nie koueskade verminder van die ‘involucral’ blare van ‘Chameleon’ en ‘Laurel Yellow’ nie, waar daar egter wel in ‘n mate beheer was veral na 28 dae vir ‘Safari Sunset’. In sommige gevalle het die voorsiening van suiker die koueskade vererger. Koueskade het oor die algemeen vinnig toegeneem na opberging gedurende die eerste drie dae in die vaas en dan teen ‘n laer tempo vir die volgende sewe dae. Leucadendron ‘Chameleon’, ‘Laurel Yellow’ en ‘Safari Sunset’ snyblom stele is voorsien van ‘n 1% (g/v) glukose oplossing. Uitgedruk op ‘n droëmassa basis is ‘n toename in glukose konsentrasie nie waargeneem nie. Die afname in koueskade van blare deur die voorsiening van ‘n suiker oplossing is gespekuleer vir die Leucospermums, om ‘n resultaat te wees van hulle teenwoordigheid in die apoplas en nie die simplas nie, en dat die teenwoordigheid daar die membrane op ‘n manier beskerm teen koue toestande.
97

Retrofit em baldios industriais urbanos e o complexo Matarazzo, Jaguariaíva – PR

Correia, Beatriz Silva 15 September 2015 (has links)
CAPES / Esta tese versa sobre práticas de retrofit, termo originário da engenharia de produtos, convocado pela Arquitetura e Urbanismo na premência de reabilitar, renovar, restaurar, reestruturar, regenerar, recompor, remodelar protegendo aspectos históricos de um edifício e incorporando-lhe tecnologia adequada aos tempos contemporâneos. O objetivo do trabalho foi percorrer e explorar aspectos relevantes destas técnicas projetuais em baldios industriais urbanos, no entendimento da diversidade socioeconômica e do desenvolvimento durável local. Apreciaram-se conceitos, modelos e conjunturas de consumo e apropriação destes recursos transformadores para a tipologia arquitetônica industrial. São retomadas as ideias de Eduardo Lozano e Amartya Sen, que destacam a diversidade sensorial e socioeconômica como motores do desenvolvimento com qualidade de vida. A pesquisa é de natureza qualitativa e elabora uma proposta de retrofit para um baldio industrial subutilizado, inserido na municipalidade de Jaguariaíva – PR. Para isso, relações singulares nas intervenções realizadas em objetos arquitetônicos semelhantes foram conectadas, seja por meio da exibição do espaço ou da heterogeneidade na apropriação individualizada destas realidades. Posteriormente, para o caso do antigo Frigorífico Matarazzo, interferências de retrofit exequíveis foram recomendadas. Elas permitiriam retomar o passado histórico em uma linguagem contemporânea. Nesse sentido, recursos técnicos propostos procuraram readequar as instalações da edificação de modo que viessem a estimular a integração entre a sustentabilidade socioeconômica e o desenvolvimento como liberdade. Recomenda-se para o conjunto edificado, a redistribuição dos espaços para outras atividades, atribuindo-lhes novas vocações que podem circular entre a transitoriedade e a permanência. Conclui-se que a proposta de retrofit para o Complexo Matarazzo formulada com base nos estudos teóricos e exemplos selecionados e analisados, permite resgatar a história, favorecer os setores de comércio e serviços, e reanimar a vida urbana ao outorgar-lhe qualidade. / This thesis addresses practices of retrofit, a term originating in product engineering, convened by the Architecture and Urbanism in the urgent need to rehabilitate, renovate, restore, restructure, remodel, regenerate, protecting historical aspects of a building, incorporating appropriate technology to present days. The objective was to explore relevant aspects of these projective techniques in urban industrial brownfields, according to the socioeconomic diversity and sustainable local development. For this, concepts, models and situations of consumption and appropriation of these resources were prized to industrial architectural typologies. They are taken up by the ideas of Eduardo E. Lozano and Amartya Sen, highlighting the sensorial and socioeconomic diversity as drivers of development with quality of life. The research is qualitative and elaborates a proposal for a retrofit to an underused industrial brownfield, inserted in the municipality of Jaguariaíva - PR. For that, unique relationships in interventions to similar architectural objects were connected, either by displaying space or heterogeneity in individual appropriation of these realities. Thereafter, for the case of the ancient Slaughterhouse Matarazzo, feasible interferences by retrofit were recommended. They would permit reclaim the historical past in a contemporary language. In this sense, the proposed technical resources were pursued to readjust the facilities, so that they might encourage the integration of the socio-economic sustainability and development as freedom. It is recommended for the built set, the redistribution of spaces for other activities, assigning them new vocations that can move between transience and permanence. It is concluded that the proposed retrofit for Matarazzo Complex formulated based on theoretical studies and on the selected and analyzed examples, allows rescue the history, favoring the sectors of trade and services, reviving urban life by granting it quality.
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Controle da qualidade sanitária em frigorífico de suínos do Paraná / Sanitary quality control within pork abattoirs in Parana

Barreto, Edith Huampa 17 November 2017 (has links)
Capes; CNPq / A manutenção das condições higiênicas na produção de alimentos é considerada peça chave na obtenção de alimentos seguros. Os ambientes dos frigoríficos apresentam uma grande quantidade de matéria orgânica rica em nutrientes que podem favorecer ao crescimento de micro-organismos A presente pesquisa objetivou a elaboração de critérios para aumentar o controle da qualidade sanitária em equipamentos e utensílios de um frigorífico de suínos do Paraná. O desenvolvimento do trabalho iniciou com as análises dos resultados microbiológicos de coleta de swabs em equipamentos e utensílios do processo após a higienização seguindo os padrões das empresas habilitadas à exportação. Com base nos conceitos das normativas que dizem respeito às condições sanitárias nos ambientes produtivos, assim com a bibliografia existente, foi elaborada e aplicada uma escala de avaliação das condições favoráveis à higiene em equipamentos e utensílios do processo. Os resultados das avaliações microbiológicas mostraram um percentual de conformidade de 75,54% para micro-organismos aeróbios mesófilos e 88,96% para as enterobactérias e uma prevalência de resultados inaceitáveis, ao longo dos períodos analisados, especificamente nas esteiras transportadoras, as quais podem representar focos de contaminação e risco no controle microbiológico das carnes. A escala desenvolvida está composta por nove critérios que avaliam as características favoráveis a higiene e as características operacionais do processo. A aplicação da escala indica que os grupos das esteiras transportadoras e os equipamentos de corte foram as que apresentaram os maiores percentuais de inadequação aos critérios. Finalmente, a prevalência de enterobactérias foi significativa (p<0,01) (ao nível de significância de 5%) para o grupo das esteiras quando comparada com os outros grupos de equipamentos, pelo que as diferenças das características nos equipamentos podem estar relacionadas com a eficiência da higienização. / Maintaining hygienic conditions in food production is considered a key part of obtaining safety food. The aim of the present work was to elaborate the criteria to increase the control of the sanitary quality in equipment and utensils of a pork abattoir in Paraná. The development of the work began with the analysis of the microbiological results of the collection of swabs in equipment and tools of the process after the hygiene, following the standards of the companies authorized to export. Based on the concepts of the standards that concern the sanitary conditions in the productive environments, as well as the existing bibliography, a scale of evaluation of the conditions favorable to hygiene in equipment and utensils of the process was elaborated and applied. The results of the microbiological evaluations showed a 75.54% compliance rate for aerobic mesophilic microorganisms and 88.96% for enterobacteria and a prevalence of unacceptable results during the analyzed periods, specifically on conveyors. represent pockets of contamination and risk in the microbiological control of meat. The scale developed is composed of nine criteria that evaluate the characteristics favorable to hygiene and the operational characteristics of the process. The application of the scale indicates that the groups of conveyors and cutting equipment were those that presented the highest percentage of inadequacy to the criteria. Finally, the prevalence of enterobacteria was significant (p <0.01) (at the significance level of 5%) for the group of conveyors when compared to the other groups of equipment, so the differences in characteristics in the equipment can be related to the hygiene efficiency.
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Fisiologia e conservação pós-colheita de flores cortadas de gérbera /

Durigan, Maria Fernanda Berlingieri. January 2009 (has links)
Resumo: Gerbera jamesonii Bolus é uma espécie da família Compositae. O capítulo, com diâmetro de 8 - 14 cm, possui flores liguladas de cores vivas organizadas ao redor do centro, que contém os botões florais. Esta inflorescência é sustentada por uma haste longa e sem folhas. Atualmente é uma das dez flores mais comercializadas no Brasil e está entre as três principais flores de corte. A utilização de soluções conservantes, tratamentos de "pulsing", ou fortalecimento, e baixas temperaturas de armazenamento visa prolongar a vida e manter por mais tempo a qualidade das flores cortadas. Neste contexto, este trabalho teve por objetivos avaliar o efeito de diferentes práticas de manejo na pós-colheita sobre a fisiologia e conservação de inflorescências de gérberas. Para os quatro primeiro experimentos foi utilizada a gérbera cv. Suzanne, de coloração laranja. Os experimentos foram conduzidos em delineamento inteiramente casualizado, em esquema fatorial. No primeiro experimento, as inflorescências permaneceram nas seguintes soluções de manutenção: 1) Água destilada; 2) Cloro a 100 mg.L-1; 3) 8-hidroxiquinolina (8-HQC) a 100 mg.L-1; 4) 8-HQC a 200 mg.L-1; e 5) 8- HQC a 400 mg.L-1, cujas hastes foram mantidas em condição controlada de laboratório (20°C; 70% UR). Este experimento possibilitou observar danos nas bases das hastes, causados pelos tratamentos com cloro a 100 mg.L-1 e com as doses mais elevadas de 8-HQC. A manutenção da boa qualidade foi observada no tratamento com 8-HQC a 200 mg.L-1. A longevidade média foi de 12 dias em vaso. No segundo experimento foram utilizadas, durante o armazenamento a 20°C e 70% UR, as soluções: 1) Água destilada; 2) Ácido cítrico a 64 g.L-1; 3) Cloro a 25 mg.L-1 4) Cloro a 50 mg.L-1 5) 8-HQC a 25 mg.L- 1 e 6) 8-HQC a 50 mg.L-1. Com os resultados verificou-se a baixa eficiência do... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Gerbera jamesonii belongs to the Compositae family. The inflorescence, with diameter of 8 - 14 cm, is a capitulum with ligules with vivid color organized around de center, that contain flower buds, which can be in a variety of colors. This colorful flower is supported by a long stem, without leaves. Nowadays it is one of the ten most commercialized flowers in Brazil and is one of the three main cut flowers. The use of keeping-quality solutions, pulsing treatments and low temperature during the vase life seeks to prolong vase life and to maintain the quality of cut flowers. In this context, this research was conducted, at FCAV-UNESP, Jaboticabal, SP, Brazil, to evaluate the effects of several handling techniques on postharvest physiology gerbera cut flowers. The experiments followed complete randomized design, in factorial arrangement. On the first one, the inflorescences remained in the following solutions: 1) Distilled water; 2) Chlorine at 100 mg.L-1; 3) 8-hydroxyquinolin (8-HQC) at 100 mg.L-1; 4) 8-HQC at 200 mg.L-1; and 5) 8-HQC at 400 mg.L-1, which the stems remained in environmental conditions (20°C; 70% RH). On this experiment, it was possible to observe the damage caused by the treatments using chlorine at 100 mg.L-1 and high dosage of 8-HQC. The good quality where kept by using 8-HQC at 200 mg.L-1 and the average longevity of the experiment was 12 days. On the second experiment, the gerberas remained, during storage, in the following solutions: 1) Distilled water; 2) Citric acid at 64 g.L-1; 3) Chlorine at 25 mg.L-14) Chlorine at 50 mg.L-1; 5) 8-HQC at 25 mg.L-1 ; and 6) 8-HQC at 50 mg.L-1. With the results it was possible to verify the low efficiency of the citric acid at the used concentration and the lower damage by lower concentrations of chlorine and 8-HQC than the usually recommended, which kept the good quality of the flowers for... (Complete abstract, click electronic access below) / Orientador: Ben-Hur Mattiuz / Coorientadora: Teresinha de Jesus Deléo Rodrigues / Banca: Regina Maria Monteiro de Castilho / Banca: Carlos Eduardo Ferreira de Castro / Banca: Káthia Fernandes Lopes Pivetta / Banca: Pedro Luís da Costa Aguiar Alves / Doutor
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Produção e qualidade de alho nobre submetido a diferentes períodos de vernalização e épocas de plantio em Baraúna, RN / Production and quality of noble garlic under different vernalization periods and planting dates in Baraúna, RN

Lopes, Welder de Araújo Rangel 26 February 2014 (has links)
Made available in DSpace on 2016-08-12T19:18:28Z (GMT). No. of bitstreams: 1 WelderARL_TESE.pdf: 839929 bytes, checksum: 680ea70cdd6f864f25ed1c5ce70efe50 (MD5) Previous issue date: 2014-02-26 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / In recent years, the use of vernalization enabled the cultivation of noble garlic (most valuable garlic in the Brazilian market) in regions where photoperiod and temperature do not meet the requirements of the crop. Given this, in order to evaluate effects of different vernalization periods and planting dates on the production and quality of the garlic Roxo Pérola de Caçador, an experiment was conducted in Baraúna, RN, between May and October 2012. The experimental design was a randomized complete block design with three replications. The treatments were arranged in splitplots with the plots by planting dates: May 22, June 5 and June 23, and the splitplots by vernalization periods garlic seed at 4 ± 1 °C: 50, 55, 60, 65 and 70 days, and 65-70% of relative humidity. Plant height, leaf number, cycle, bulb final stand, average bulb weight, percentage of bulbs differentiation of cloves, percentage of oversprouting plants, total yield of bulbs, classification of bulbs, number of cloves per bulb, classification of cloves, bulb diameter, soluble solids, total soluble sugars, tritable acidity, pH, SS/AT ratio, pungency, total solids and industrial index were evaluated. The planting on May 22 gave higher plant height, leaf number, final stand and average bulb weight; the cycle decreased with increasing time of vernalization; were formed bulbs with differentiation of cloves in all treatments, and absence of oversprouting of plants; total bulb yield increased with time until 63 days of vernalization during at plantations of May 22 and June 23, with averages of 5.20 and 3.85 t ha-1; by combining the planting on May 22 time and 65 days of vernalization, showed the highest number of cloves per bulb (7.51) and the highest percentage of commercial bulbs, which are distributed in classes 3 (32 to 37 mm diameter), 4 (37 to 42 mm diameter) and 5 (42 to 47 mm diameter). For attributes of quality, the increased length of vernalization up to 64 days allowed in increments bulb diameter and soluble solids, with maximum of 34.5 mm and 33.65%, respectively; the highest levels of total soluble sugars, bulb diameter and soluble solids were obtained at planting on May 22; the tritable acidity increased with time vernalization during plantations of 5 and 23 June, when there was a reduction in SS/AT ratio; and in general, all treatments allowed high total solids and simultaneous pungency, with good prospects for industrialization. Thus, we recommend planting the cultivar Roxo Pérola de Caçador on Baraúna/RN, in the second half of May, using 65 days of vernalization / Nos últimos anos, o uso da vernalização possibilitou o cultivo de alho nobre em regiões nas quais as condições de fotoperíodo e temperatura não satisfazem as exigências da cultura. Diante disso, a fim de avaliar os efeitos de diferentes períodos de vernalização e épocas de plantio sobre a produção e qualidade do alho Roxo Pérola de Caçador, realizou-se um experimento em Baraúna, RN, de maio a outubro de 2012. O delineamento experimental adotado foi o de blocos casualizados completos, com três repetições. Os tratamentos foram dispostos em parcelas subdivididas, sendo as parcelas repre¬sentadas pelas épocas de plantio: 22 de maio, 5 de junho e 23 de junho, e as subparcelas pelos períodos de vernalização pré-plantio do alho-semente a 4 ± 1°C: 50, 55, 60, 65 e 70 dias, e umidade relativa de 65-70%. Foram avaliados: altura de plantas, número de folhas, ciclo, estande final, massa média de bulbos, percentagem de bulbos com diferenciação de bulbilhos, percentagem de superbrotamento de plantas, produtividade total de bulbos, classificação dos bulbos, número de bulbilhos por bulbo, classificação dos bulbilhos, diâmetro de bulbo, sólidos solúveis, açúcares solúveis totais, acidez titulável, pH, relação SS/AT, pungência, sólidos totais e índice industrial. O plantio em 22 de maio proporcionou altura de planta, número de folhas, estande final e massa média de bulbos superior às demais épocas de plantio; o ciclo decresceu com o aumento do tempo de vernalização; houve formação de bulbos com diferenciação de bulbilhos em todos os tratamentos e ausência de superbrotamento de plantas; a produtividade total de bulbos aumentou com o tempo de vernalização até 63 dias para os plantios em 22 de maio e 23 de junho, com médias de 5,20 e 3,85 t ha-1; por meio da combinação entre o plantio em 22 de maio e 65 dias de vernalização, foi obtido o maior número de bulbilhos por bulbo (7,51) e o maior percentual de bulbos comerciais, sendo estes distribuídos nas classes 3 (maior que 32 até 37 mm), 4 (maior que 37 até 42 mm) e 5 (maior que 42 até 47 mm). Para os atributos de qualidade, o aumento do tempo de vernalização até 64 dias possibilitou incrementos no diâmetro de bulbos e sólidos solúveis, com máximos de 34,5 mm e 33,65%, respectivamente; os maiores teores de açúcares solúveis totais, diâmetro de bulbos e sólidos solúveis foram obtidos no plantio em 22 de maio; a acidez titulável aumentou com o tempo de vernalização nos plantios de 5 e 23 de junho, quando houve redução na relação SS/AT. De modo geral, todos os tratamentos possibilitaram elevados teores de sólidos totais e pungência simultâneos, com boas perspectivas para a industrialização. Desta forma, recomenda-se o plantio da cultivar Roxo Pérola de Caçador em Baraúna/RN, na segunda quinzena de maio, utilizando-se 65 dias de vernalização

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