Made available in DSpace on 2016-12-08T16:44:44Z (GMT). No. of bitstreams: 1 PGPV11MA024.pdf: 427943 bytes, checksum: 58b5ba9bfed00545754a51ffa79cc684 (MD5) Previous issue date: 2011-09-23 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The objective of this work was to evaluate the effect of maturity stage of fruits in harvest, different storage temperatures and techniques complementary to controlled atmosphere (induction of fresh mass loss, 1-methylcyclopropene and ethylene absorption) on the ripening and quality of Laetitia plums. Two different and independent experiments were performed in 2010, with fruits harvested in commercial orchard from Vacaria-RS in the second experiment. The first experiment evaluated the following treatments: 35 days storage temperature (-0,5°C; 0,0°C; 0,5°C) combined with two maturity stages of fruits at harvest (M1: 25-30% red; M2: 50-80% red). In the second experiment the storage was for 55 days and were evaluated the treatments cold storage (CS; 21 kPa O2 + < 0,03 kPa CO2), controlled atmosphere (CA), CA + 1-MCP (1,0 &#956;L L-1), CA + induction of fresh mass loss (IFML) and CA + ethylene absorption. In both experiments variables assessed were: flesh firmness, texture attributes (strength to rupture of the skin, strength to pulp penetration and strength for compression of fruit), red color index, color of skin (h0), incidence and severity of flesh browning, soluble solids (SS), titratable acidity (TA), respiratory rate and rot and cracking incidence. The evaluations were realized after the storage and after three days for simulation of comercialization. Plums harvested at stage M1 showed less red skin and larger values of titratable acidity, flesh firmness and forcesto skin rupture, penetration of the pulp and fruit compression, after 35 days of storage and more 3 days of shelf life. After storage, fruits of the stage M1 and stored at 0°C exhibited lower flesh browning intensity than the fruits of stage M2 and -0,5°C e 0,5°C, respectively.. Temperature of -0.5°C provided less red skin and larger values of flesh firmness and texture attributes. CA delay the fruit ripening and reduce the rot and cracking incidence and, at removal from cold storage, flesh browning incidence and severity. The IFML, ethylene absorption and 1-MCP, as a complement to controlled atmosphere, contributed to better maintenance of flesh firmness and texture attributes, after 3 days of shelf life. The IFML and 1-MCP provided fruit with lower flesh browning severity. Plums harvested with 25-30% of the surface of red fruits and stored at 0,0°C shows better maintenance of physicochemical quality and smaller flesh browning severity. Complementary to CA, IFML and 1-MCP, contributes to better maintenance the fruit consistency and lower flesh browning severity / O objetivo deste trabalho foi avaliar o efeito do estádio de maturação dos frutos no momento da colheita, diferentes temperaturas de armazenamento e de técnicas complementares a atmosfera controlada (indução de perda de massa fresca, 1 metilciclopropeno e absorção de etileno) sobre o amadurecimento e a qualidade de ameixas Laetitia . Foram realizados dois experimentos distintos e independentes, durante o ano de 2010 com frutos colhidos em pomar comercial de Vacaria-RS. O primeiro experimento avaliou temperatura de armazenamento por 35 dias (-0,5ºC; 0,0ºC; 0,5ºC) combinado com dois estádios de maturação dos frutos no momento da colheita (M1 com 25 a 30% da epiderme com cor vermelha e M2 com 50 a 80% da epiderme com cor vermelha). No segundo experimento o armazenamento foi por 55 dias e foram avaliados os tratamentos atmosfera refrigerada (AR; 21 kPa de O2 + <0,03 kPa de CO2), atmosfera controlada (AC), AC com aplicação de 1-metilciclopropeno (1-MCP; 1,0 &#956;L L-1), AC com indução de perda de massa fresca (IPMF) e AC com absorção de etileno. Em ambos experimentos as variáveis avaliadas foram: firmeza de polpa, atributos de textura (forças para ruptura da epiderme, penetração da polpa e compressão do fruto), índice de cor vermelha (ICV), cor da epiderme (ho), incidência e severidade de escurecimento da polpa (L), sólidos solúveis (SS), acidez titulável (AT), taxa respiratória e incidência de podridões e rachaduras. As avaliações foram realizadas após o armazenamento e novamente depois de três dias para simulação da comercialização. No experimento 1, as ameixas colhidas no estádio M1 apresentaram epiderme menos vermelha e maiores valores de acidez titulável, firmeza de polpa e de forças para ruptura da casca, penetração da polpa e compressão do fruto, após 35 dias de armazenamento e mais três dias em condições ambientes. Após o armazenamento, os frutos do estádio M1 apresentaram menor intensidade de escurecimento da polpa que os frutos do estádio M2. De maneira geral, a temperatura de -0,5ºC proporcionou frutos menos vermelhos e com maiores valores de firmeza de polpa e atributos de textura. A AC retardou o amadurecimento dos frutos e reduziu a incidência de podridões e rachaduras e, na saída da câmara, a incidência e severidade de escurecimento da polpa. A IPMF, absorção de etileno e o 1-MCP, como complemento à atmosfera controlada, contribuíram para melhor manutenção da firmeza de polpa e atributos de textura, após três dias de exposição dos frutos em condições ambiente. A IPMF e o 1-MCP proporcionaram frutos com menor severidade de escurecimento da polpa. Conclui-se que frutos colhidos em estádio M1 e armazenados na temperatura de 0,0oC apresentam melhor manutenção das qualidades físico-químicas e menor severidade de escurecimento da polpa. O uso complementar a atmosfera controlada, da IPMF e 1-MCP, contribui para melhor manutenção da consistência do fruto e reduz a severidade do escurecimento da polpa

A ameixeira Gulfblaze, também conhecida como FLA 87-7, é uma cultivar de ameixa japonesa que se destaca pelo tamanho do fruto, precocidade de produção e resistência a escaldadura das folhas, doença que tem sido entrava a produção de ameixas no Brasil. Essa cultivar foi incorporada ao Banco Ativo de Germoplasma (BAG) do IAC por volta das décadas de 60 e 70, mas ainda há poucos trabalhos no tocante a informações sobre sua a fisiologia, conservação e armazenamento pós-colheita. As ameixas apresentam, geralmente, um curto período pós-colheita, sendo necessárias tecnologias para aumentar seu tempo de armazenamento e a manutenção da qualidade, as quais visam, sobretudo, a minimização dos efeitos deletérios causados pelo etileno, desde a maturação até o momento da chegada ao consumidor. Para sugerir melhorias no manejo e conservação da qualidade pós-colheita e promover maior longevidade da ameixa \"Gulfblaze\", alguns experimentos foram realizados. Desses experimentos, surgiram três trabalhos. O primeiro trabalho investigou o ponto de colheita ideal baseado no estado de maturação. No segundo, foi investigado o uso da refrigeração associado ao 1-MCP para prolongar o tempo de armazenamento. E no terceiro, foi testada a hipótese de que a aplicação do etileno poderia reiniciar o processo regular de amadurecimento de frutos refrigerados, interrompido pelo 1-MCP, e uniformizar o amadurecimento. A ameixa \"Gulfblaze\" apresenta padrão climatérico de amadurecimento, e quando colhida com casca apresentando 50 a 75% da coloração característica da cultivar apresentam maturação regular e maior potencial para comercialização e consumo, com longevidade comercial de 10 dias em temperatura ambiente (25°C). Sob essas condições, a firmeza dos frutos no momento da colheita é adequada ao transporte e são visualizados melhores resultados para os índices de qualidade, tais como sólidos solúveis e relação sólidos solúveis/acidez titulável, ao longo do período de armazenamento. A aplicação de 1-MCP retarda o pico climatérico em ameixa \"Gulfblaze\". Aplicação de 450 nL L-1 de 1-MCP seguido do armazenamento a 1°C mantém a qualidade desses frutos durante 36 dias de armazenamento refrigerado, proporcionando firmeza, cor e sabor adequados a comercialização e consumo mesmo após seis dias de armazenamento a 25°C. A aplicação de etileno em ameixa \"Gulfblaze\" tratada com 1-MCP não provocou aumento na atividade respiratória e na produção de etileno, tampouco antecipou o climatérico. Embora a perda de massa e a acidez titulável nos frutos tratados com 1-MCP e etileno tenha sido maior que nos demais tratamentos, essa combinação permitiu a manutenção da coloração da casca mais próxima daquela observada na colheita e proporcionou maiores valores para o teor de sólidos solúveis e atividade antioxidante. A aplicação de 1-MCP e etileno aos 18 dias proporcionou maior conteúdo de antocianina na casca e maior teor de vitamina C na polpa. A aplicação do 1-MCP inibiu o surgimento de injúrias por frio, mesmo em frutos tratados com etileno. / The Gulfblaze plum, also known as FLA 87-7, is a Japanese plum cultivar that stands out for fruit size, earliness and resistance to the leaf scald disease, which has been hindering the production of plums in Brazil. This cultivar was incorporated into the Active Germplasm Bank of IAC around the \'60s and \'70s, but there are few papers related to information about their physiology, conservation and post-harvest storage. Plums have a short post-harvest period, and further technology is necessary to increase their shelf life and maintain quality, primarily by minimizing the deleterious effects of ethylene from ripening until the time of arrival to the consumer. In order to suggest improvements in the management and conservation of postharvest quality and promote longevity plum \'Gulfblaze\', some experiments were carried out. Three studies resulted from these experiments: The first study investigated the point of ideal harvest based on ripeness, the second one investigated refrigeration associated with 1-MCP to extend the storage time, and the third paper tested the hypothesis that the application of ethylene could restart the regular process of maturation of chilled fruit, interrupted by 1-MCP, and uniform ripening. \'Gulfblaze\' plums exhibit a climacteric ripening pattern, and when harvested within 50-75% of a cultivar\'s characteristic color, they have regular maturation with an brand longevity of 10 days at room temperature (25°C). In that condition, the fruit has greater potential for marketing and consumption, with a proper firmness transport at harvest and better results for the quality indexes such as soluble solids and soluble solids / titratable acidity during the storage period. The application of 1-MCP slows the climacteric peak in \'Gulfblaze\' plums. Application 450 nL L-1 1-MCP followed by storage at 1°C maintains the quality of the fruit during 36 days of cold storage, providing firmness, color and flavor suitable for marketing and consumption even after six days of storage at 25°C. The application of ethylene in \'Gulfblaze\' plums treated with 1-MCP did not cause an increase in respiratory activity and ethylene production, nor did it anticipate the climacteric. Although weight loss and titratable acidity in fruit treated with 1-MCP and ethylene was higher than other treatments, this combination allowed the maintenance of the peel color closer to that observed at harvest, and it gave higher values for the solids and soluble antioxidant activity. The application of 1-MCP and ethylene in the 18th day showed higher content of anthocyanin in the skin and higher content of vitamin C in the pulp. The application of 1-MCP inhibited the incidence of chilling injuries, even in ethylene treated fruit.

Made available in DSpace on 2014-08-20T13:59:15Z (GMT). No. of bitstreams: 1 dissertacao_daniela_de_conti.pdf: 1033668 bytes, checksum: 84993fae9dbf6d00292f67eaacda30fb (MD5) Previous issue date: 2012-02-15 / The Japanese plum (Prunus salicina Lindl.) is a fruit of great prominence worldwide. In Brazil, one of the most widely cultivated species of plum, because it presents climatic conditions favorable to its cultivation. However, some factors limit the increase in domestic production of plum trees, among them stands out the gametophytic self-incompatibility, due to the presence of a multiallelic codominant locus, containing the so-called S-alleles. Thus, the objective of this study was to identify physiologically and molecularly S-alleles of Japanese plum cultivars related to gametophytic self-incompatibility. For physiological characterization were carried out controlled pollination experiments in the experimental field of Embrapa, Clima Temperado (Pelotas/RS) and the pollination in vivo in laboratory, three cultivars of Japanese plum (América, Gulf Rubi and Gulf Blaze) which were evaluated fruit set and pollen tube growth (CTP), respectively. For molecular characterization, experiments were performed in the Laboratory of Plant Tissue Culture and Molecular Characterization, (UFPel / RS). To this end, we analyzed 19 Japanese plum cultivars by Polymerase Chain Reaction (PCR) with two pairs of specific primers for amplification of S-alleles. Crossings 'Gulf Blaze' x Gulf Rubi' Gulf Rubi x 'Gulf Rubi' and 'Gulf Rubi' x 'Gulf Blaze' had a fruit set of 11.36%, 3.84% and 9.94% respectively. In vivo pollination CTP reached the egg or ovarian in these crosses, with the exception of self-pollination of 'Gulf Rubi'. There was no fruit set in the field, self-pollination in 'América' and 'Gulf Blaze' and crossing 'América x' Pluma 7 '. The CTP in these crosses did not reach the egg, with the exception of self-pollination of 'Gulf Blaze'. Only the cross between 'América' x 'Pluma 7' are incompatible, and America is a self-incompatible cultivar. In amplification of S-alleles was possible to obtain the effective characterization of alleles-S of cultivars studies, as well as, the choice of pollinating more compatible with the cultivars producing. The cultivars América and Santa Rosa; Blood Plum, Wickson, Rosa Mineira, Estrela Púrpura and Planta 21 showed incompatibility between them. / A ameixeira japonesa (Prunus salicina Lindl.) é uma frutífera de grande destaque mundialmente. No Brasil, é a espécie de ameixeira mais cultivada, pois apresenta grande número de cultivares adaptadas as diferentes condições climáticas das regiões onde é cultivada. Porém, alguns fatores limitam o aumento da produção nacional de ameixeiras, entre eles destaca-se a autoincompatibilidade gametofítica, devido à presença de um loco multialélico, contendo os denominados alelos-S. Diante disso, o objetivo deste trabalho foi identificar fisiologicamente e molecularmente os alelos-S de cultivares de ameixeira japonesa relacionados à autoincompatibilidade gametofítica. Para a caracterização fisiológica, realizaram-se experimentos de polinização controlada no campo experimental da Embrapa Clima Temperado (Pelotas/RS) e polinização in vivo, em laboratório, de três cultivares de ameixeira japonesa (América, Gulf Blaze e Gulf Rubi) onde foram avaliados a frutificação efetiva e o crescimento do tubo polínico (CTP), respectivamente. Para a caracterização molecular, os experimentos foram realizados no Laboratório de Cultura de Tecidos de Plantas Caracterização Molecular, (UFPEL/RS). Para tal fim, foram analisadas 19 cultivares de ameixeira japonesa, por meio de Reação em Cadeia da Polimerase (PCR) com dois pares de primers específicos para amplificação de alelos-S. Nos estudos de compatibilidade reprodutiva, a cv. América apresentou alto fruit set quando polinizada com as cvs. Rosa Mineira (26,7%), Amarelinha (8,7%) e Reubennel (12,7%). Os cruzamentos Gulf Blaze x Gulf Rubi , Gulf Rubi x Gulf Rubi e Gulf Rubi x Gulf Blaze obtiveram um fruit set de 11,36%, 3,84% e 9,94%, respectivamente. Na polinização in vivo o CTP atingiu o óvulo ou ovário nesses cruzamentos, com exceção da autopolinização da Gulf Rubi . Não houve frutificação efetiva, no campo, na autopolinização América e Gulf Blaze e no cruzamento América x Pluma 7 . O CTP nesses cruzamentos não chegou a atingir o óvulo, com exceção da autopolinização da Gulf Blaze . Apenas os cruzamentos América x Pluma 7 são incompatíveis e a cultivar América é autoincompatível. Na amplificação de alelos-S, foi possível obter a efetiva caracterização de alelos-S das cultivares estudadas, bem como, a escolha das polinizadoras mais compatíveis com as cultivares produtoras. Verificou-se que as cultivares América e Santa Rosa; Blood Plum, Wickson, Rosa Mineira, Estrela Púrpura e Planta 21, apresentaram incompatibilidade entre si.

Thesis (MSc Food Sc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Phenolic compounds of the types present in plums have been found to exhibit health-promoting properties associated with their antioxidant capacity. Fruits with red peel and/or flesh are thus sought-after for their high antioxidant levels. In the current study South African plum (Prunus salicina Lindl.) cultivars and selections, harvested during two consecutive fruit seasons, were compared in terms of general fruit attributes (colour, firmness, °Brix, pH, titratable acidity), phenolic composition and antioxidant capacity. The effect of season and a commercial cold storage and ripening regime was also investigated. A reversed-phase high-performance liquid chromatography-diode-array-fluorescence detection (HPLC-DAD-FLD) method suitable for use with mass spectrometry (MS) detection, was optimised for separation and identification of phenolic compounds from four phenolic groups (phenolic acids, anthocyanins, flavan-3-ols and flavonols) in six South African plum cultivars and five selections. Parameters that were optimised include the mobile phases, analysis temperature and gradient program. Good stability, linearity and inter- and intra-day precision were obtained. Identification of compounds was based on comparison of retention times, UV-Vis spectra and mass fragments with available authentic phenolic standards and/or literature data. The optimised method allowed identification or tentative identification of twenty-four phenolic compounds, including cyanidin-3-O-glycosides, quercetin glycosides, monomeric, dimeric and trimeric flavan-3-ols, and hydroxycinnamic acids. An on-line ABTS•+ (2,2ʹ-azinobis-(3-ethyl-benzothiazoline-6-sulfonic acid)) antioxidant assay, performed for qualitative evaluation of the antioxidant response of individual phenolic compounds, indicated the flavan-3-ols as major antioxidants in plums. Eighteen phenolic compounds were quantified, including anthocyanins and flavonol glycosides, flavan-3-ols (monomers and dimers) and hydroxycinnamic acids. Phenolic composition differed greatly between cultivars and selections. Cyanidin-3-O-glucoside was the predominant anthocyanin in plums with red peel and/or flesh, followed by cyanidin-3-O-rutinoside. Cyanidin-3-O-galactoside was present only in the cultivar Laetitia (red peel, yellow flesh). The ripe fruit of Ruby Red and PR04-19, both with red peel and flesh, had the highest anthocyanin content for the first and second harvest season, respectively. Neochlorogenic acid and quercetin-3-O-glucoside were the major phenolic acid and flavonol, respectively. Chlorogenic acid, 3-O-p-coumaroylquinic acid and several quercetin-glycosides and -diglycosides were also present in some cultivars and selections. Procyanidin B1 was the flavan-3-ol present in the highest concentration in the majority of cultivars and selections and its content correlated with the (+)-catechin content, while the same was observed for procyanidin B2 and (-)-epicatechin. The effect of cold storage and ripening on fruit attributes differed greatly between cultivars and selections. The increase and decrease in pH and titratable acidity, respectively, were as expected for ripe fruit as opposed to unripe fruit. Ripe fruit had higher a*-values and lower L*-values. The cold storage and ripening regime had no significant effect on total polyphenol and total flavan-3-ol content of the cultivars and selections, but the anthocyanin content increased in some cases. In terms of in vitro antioxidant capacity, the selections PR04-32 and PR04-35, both with red peel and flesh, had the highest antioxidant capacity, irrespective of assay. Sapphire (red peel, yellow flesh), with the lowest total polyphenol content, also had the lowest antioxidant capacity in the ORAC and FRAP assays. Both the total polyphenol and flavan-3-ol contents correlated significantly to antioxidant capacity, irrespective of assay. / AFRIKAANSE OPSOMMING: Fenoliese verbindings, soos teenwoordig in pruime, is bekend vir hul gesondheidsbevorderende eienskappe wat geassosieer word met antioksidant kapasiteit. Vrugte met ‘n rooi skil en/of vleis is veral gesog as gevolg van hul hoë antioksidant aktiwiteit. Met hierdie studie is Suid-Afrikaanse pruim (Prunus salicina Lindl.) kultivars en seleksies, geoes tydens twee opeenvolgende seisoene, vergelyk in terme van algemene vrug einskappe (kleur, fermheid, °Brix, pH en titreerbare suurheid), fenoliese samestelling en antioksidant kapasiteit. Die effek van ‘n kommersiële koelopberging en rypwording prosedure is ook ondersoek. ‘n Omgekeerde-fase hoë-druk vloeistof chromatografie (HPLC) metode met diode-opstelling en fluoressensie deteksie, maar wat ook geskik is vir massa spektrometrie (MS), is geoptimiseer om fenoliese verbindings te skei en te identifiseer in Suid-Afrikaanse pruime. Verbindings van vier fenoliese groepe (fenoliese sure, antosianiene, flavan-3-ole en flavonole) wat in ses kultivars en vyf seleksies voorgekom het, is ondersoek. Die vloeistof fases, skeidingstemperatuur en gradiënt van die metode is geoptimiseer. Goeie resultate vir stabiliteit, lineariteit en inter- en intra-dag akkuraatheid is verkry. Verbindings is geïdentifiseer deur vergelyking van retensie tye, UV-Vis spektra en massa fragmente met dié van egte fenoliese standaarde en/of met literatuur data. Vier-en-twintig fenoliese verbindings is geïdentifiseer of voorlopig geïdentifiseer, insluitende sianidien- en kwersetien glikosiede, flavan-3-ol monomere, dimere en trimere, en hidroksikaneelsure. ‘n Aanlyn ABTS•+ (2,2 ʹ-azino-di-(3-etielbensotialosien-sulfoon suur) radikaal katioon blussingstoets is gebruik om die antioksidant reaksie van individuele polifenole op ‘n kwalitatiewe wyse te evalueer en flavan-3-ole is as hoof antioksidante in pruime aangetoon. Kwantifisering van agtien verbindings, insluitende antosianiene, flavonol glikosiede, flavan-3-ole (monomere en dimere) en hidroksikaneelsure, was moontlik met hierdie geoptimiseerde metode. Die fenoliese samestelling het aansienlik verskil tussen kultivars en seleksies. Sianidien-3-O-glukosied was die hoof antosianien in pruime met ‘n rooi skil en/of vleis, gevolg deur sianidien-3-O-rutinosied. Sianidien-3-O-galaktosied het slegs in Laetitia (rooi skil en geel vleis) voorgekom. Ryp vrugte van Ruby Red en PR04-19, beide met rooi skil en vleis, het onderskeidelik die hoogste antosianieninhoud gehad met die eerste en tweede seisoen se oeste. Neochlorogeniese suur en kwersetien-3-O-glukosied was die hoof fenoliese suur en flavon-3-ol, onderskeidelik. Chlorogeniese suur, 3-O-p-kumarienkwiniensuur en verskeie kwersetien glikosiede en diglikosiede was teenwoordig in sekere kultivars/seleksies. Die flavan-3-ol, prosianidien B1, was teenwoordig in die hoogste konsentrasie in die meerderheid kultivars/seleksies. Die prosianidien B1 inhoud het met die (+)-katekien inhoud gekorreleer, terwyl dieselfde gevind is vir prosianidien B2 en (-)-epikatekien. Die effek van koelopberging en rypwording op die algemene vrug einskappe het tussen kultivars en seleksies verskil. Die pH en titreerbare suurheid het onderskeidelik toegeneem en afgeneem, soos verwag is vir ryp vrugte teenoor onryp vrugte. Ryp vrugte het hoër a*-waardes en laer L*-waardes getoon. Koelopberging en rypwording het geen beduidende effek op die totale polifenol- en totale flavan-3-ol inhoud gehad nie, maar die antosianieninhoud het vir sommige kultivars en seleksies toegeneem. In terme van in vitro antioksidant kapasiteit het die seleksies PR04-32 en PR04-35, beide met rooi skil en vleis, die hoogste antioksidant kapasiteit getoon, ongeag die antioksidant toets wat gebruik is. Sapphire (rooi skil en geel vleis) het die laagste totale polifenolinhoud gehad, asook die laagste antioksidant kapasiteit soos bepaal deur die ORAC en FRAP toetse. Beide die totale polifenol- en flavan-3-ol inhoud het beduidend met die antioksidant kapasiteit korreleer, ongeag van die toets wat gebruik is.

Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: In order to export South African plums to overseas markets strict quality standards must be maintained. Among these quality classifications are specifications about the presence of cavities and pieces of broken stone/pit within the flesh of the fruit. If more than 10% of the fruit in a carton are affected by severely broken stones or large flesh cavities, the fruit have to be marketed as Class 2. A substantial amount of plums destined for export from South Africa is affected by broken stones and thus have to be marketed as Class 2. Lower prices are attained for Class 2 fruit, therefore, the presence of broken stones has a detrimental effect on the income generated from these fruit. The main aim of this study was to gain a better understanding of broken stone development and compare the growth characteristics of Japanese plum cultivars differing in their susceptibility to broken stones. Stone breakage in ‘Laetitia’ was observed as soon as stone hardening was initiated. At the start of stone hardening the parts of the stone that are still ‘soft’ are not strong enough to resist the pulling forces of the growing mesocarp and the stone is subsequently pulled apart. Regression analysis indicated that lengthwise growth of the fruit, fresh weight of the endo- and mesocarp, minimum orchard temperature and orchard night temperature, and relative humidity (RH) early in the growing season could possibly be used to predict the incidence of broken stones at harvest. Differences in the incidence of broken stones were observed between ‘Laetitia’, ‘Sapphire’ and ‘Songold’ plums and between seasons. Furthermore, significant differences were observed in the density of the endocarp in different parts of the stone. For ‘Laetitia’ and ‘Songold’, stone breakage was observed when rapid increases in stone density coincided with rapid increases in fruit growth. The stones broke in positions where an interface exists between high and low density parts in the stone and when rapid radial growth takes place in the direction where the stone is least dense. In contrast, in ‘Sapphire’, stone breakage was observed before the stones had started to lignify, indicating that the endocarp was pulled apart by the expanding flesh because it was too soft to withstand the strong pulling forces created by the flesh. The incidence of broken stones was influenced by environmental factors, as higher temperatures during the stone development and hardening period could lead to more complete endocarp formation (more stone cells are formed under such conditions). Such fruit would thus have higher endocarp density, which, if coupled with rapid radial growth, could lead to a higher incidence of broken stones. Foliar and/or root applications of calcium nitrate and potassium silicate were applied to ‘Laetitia’ plums to determine whether the incidence of broken stones could be reduced by increasing the strength of the endocarp cell walls. However, no such effect was observed. Hence, neither calcium nor silicate treatments can be recommended for reducing broken stones in plums. / AFRIKAANSE OPSOMMING: Om Suid-Afrikaanse pruime na oorsese markte uit te voer moet vrugte aan streng kwaliteitstandaarde voldoen. Daar is ondermeer spesifikasies in verband met die teenwoordigheid van holtes en stukkies gebreekte pit binne die vrug. Indien meer as 10% van die vrugte in ʼn karton deur ernstige gebreekte pit of groot vrugholtes geaffekteer word, moet die vrugte as Klas 2 bemark word. Aangesien ʼn groot hoeveelheid van die pruime wat vir uitvoer bestem is, geaffekteer word deur gebreekte pit en gevolglik as Klas 2 bemark moet word, word aansienlike finansiële verliese gelei. Laer pryse word behaal vir Klas 2 vrugte, en dus het die teenwoordigheid van gebreekte pitte ʼn negatiewe effek op die wins wat deur die uitvoer van hierdie vrugte gegenereer kan word. Die hoofdoel van hierdie studie was om die ontwikkeling van gebreekte pit in Japannese pruime te ondersoek en om die groei-patrone van kultivars wat geneig is tot gebreekte pit te vergelyk met ʼn nie-sensitiewe kultivar. Gebreekte pit in ‘Laetitia’ is opgemerk sodra die pit begin verhard het. Met die aanvangs van pit- verharding is die gedeeltes van die pit wat nog nie volkome verhard het nie, nie sterk genoeg om die sterk trekkragte van die groeiende mesokarp te weerstaan nie en die pit word gevolglik uitmekaar- getrek. Regressie-analise het gewys dat lengtegroei van die vrugte, vars massa van die endo- en mesokarp, minimum boordtemperatuur en boord-nagtemperatuur, asook relatiewe humiditeit gedurende die vruggroei-periode moontlik gebruik kan word om die voorkoms van gebreekte pit by oes te voorspel. Verskille in die voorkoms van gebreekte pit is opgemerk tussen ‘Laetitia’, ‘Sapphire’ en ‘Songold’ pruime, en ook tussen seisoene. Verder is beduidende verskille opgemerk in die digtheid van die endokarp in verskillende dele van die pit. By beide ‘Laetitia’ en ‘Songold’ is gebreekte pit opgemerk wanneer vinnige toename in pit-digtheid saamgeval het met ʼn vinnige toename in vruggroei. Die pitte breek veral in die oorgang tussen dele van die pit met hoë en lae digtheid en as dit gekombineer is met vinnige radiale vruggroei in die rigting waar die pit die minste dig is. In teenstelling hiermee is gebreekte pit in ‘Sapphire’ opgemerk selfs voordat die pitte begin verhard het. Dit dui daarop dat die endokarp uitmekaargetrek is deur die vinnig groeiende mesokarp, omdat dit te sag was om die trekkragte van die groeiende vrugvlees te weerstaan. Die voorkoms van gebreekte pit word ook deur weerstoestande beïnvloed, want hoër temperature gedurende die pit-ontwikkeling en verhardingsperiode, kan lei tot die ontwikkeling van endokarpe met meer steenselle. Hierdie vrugte sal dus ʼn hoër digtheid hê, en as dit saamval met vinnige radiale groei, kan dit lei tot ʼn groter voorkoms van gebreekte pit. Blaar- en/of worteltoedienings van kalsiumnitraat en kaliumsilikaat is gemaak om te bepaal of die voorkoms van gebreekte pit in ‘Laetitia’ verminder kon word deur die versterking van die endokarp-selwande. Geen van hierdie behandelings het tot ʼn vermindering in gebreekte pit gelei nie en nie kalsiumnitraat of kaliumsilikaat kan dus aanbeveel word om gebreekte pit in pruime te verminder nie.

Made available in DSpace on 2014-06-11T19:32:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-06-17Bitstream added on 2014-06-13T19:22:04Z : No. of bitstreams: 1 costa_sm_dr_botfca.pdf: 644719 bytes, checksum: e6ca1b81aea205b531d4ed5454c33d82 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Este trabalho teve como objetivo prolongar a vida útil de ameixas cv. Gulfblaze, provenientes de Holambra II – SP, com o emprego da irradiação gama, embalagem e o uso de condicionamento térmico em frutos refrigerados. Foram realizados dois experimentos: Experimento 1 - frutos irradiados (0,0; 0,4; 0,6; 0,8; 1,0kGy) submetidos à atmosfera modificada passiva e Experimento 2 - frutos submetidos ao condicionamento térmico (10±2°C por 2 dias), irradiados (0,0; 0,4; 0,6; 0,8; 1,0kGy) submetidos à atmosfera modificada passiva. Os frutos foram selecionados e embalados para então serem irradiados no IPEN, localizado em São Paulo – SP. Logo após seguiram para o Laboratório de Frutas e Hortaliças, pertencente ao Departamento de Gestão e Tecnologia Agroindustrial, da Faculdade de Ciências Agronômicas – UNESP – Câmpus de Botucatu, SP. Nos dois experimentos, os frutos após os tratamentos, foram armazenados em B.O.D. a 0±2°C e com 90±5% de UR por 35 dias. As avaliações foram realizadas a cada cinco dias, durante 35 dias de armazenamento. As alterações na qualidade pós-colheita foram detectadas por meio das análises de perda de massa fresca, firmeza, pH, acidez titulável, sólidos solúveis, razão SS/AT “Ratio” açúcares redutores, açúcares totais, vitamina C total, pigmentos, compostos fenólicos totais e taxa de respiração. O delineamento estatístico empregado foi inteiramente casualizado com três repetições por tratamento para cada um dos oito tempos de avaliação, utilizando-se o Teste de Tukey a 5% de probabilidade. Nas condições em que os experimentos foram realizados, os resultados permitem concluir que, os frutos da ameixeira ‘Gulfblaze’ são resistentes à refrigeração (0±2°C), não apresentando sintomas de injúria até os 35 dias de armazenamento. O condicionamento levou a uma aceleração do amadurecimento, mostrando-se não recomendável para essa variedade de ameixas / The present work aims at protracting the lifespan of plums cv. Gulfblaze, originating from Holambra II, São Paulo, by application of gamma irradiation, packaging and the use of thermal conditioning on cold fruits. Two experiments were made: Experiment 1. irradiated fruits (0,0; 0,4; 0,6; 0,8; 1,0KGy) undergo a passive modified atmosphere and Experiment 2. fruits undergo thermal conditioning (10±2°C for 2 days), irradiation (0,0; 0,4; 0,6; 0,8; 1,0KGy), and are subjected to passive modified atmosphere. The fruits were selected and packed, and then irradiated at IPEN, located in São Paulo – SP. Thereupon, they were directed to the Laboratory of Fruit and Vegetables from the Department of Management and Agribusiness Technology of the Agronomic Sciences Faculty - UNESP - Botucatu, Brazil. In both experiments, after the treatment the fruits were stored in B.O.D at 0±2°C with 90±5% RH for 35 days. Evaluations were conducted every five days, for the 35 days of storage. Alterations on post-harvest quality were detected by means of analysis of fresh mass loss, consistency (firmness), pH, total titratable acidity, soluble solids, ‘Ratio’ (SS/TTA), reducing sugar content, total reducing sugar, vitamin C total, pigment, phenolic compounds and respiratory rates. The employed statistical design was thoroughly randomized with three replications per treatment for each of the eight evaluations using the Turkey’s Test to 5% of probability. Under the circumstances in which the experiments were performed, the results allow for the conclusion that ‘Gulfblaze’ plum fruits are resistant to refrigeration (0±2°C), with no symptoms of injury during the 35 days at storage. The conditioning led to ripening acceleration, proving to be not advisable for this sort of plum. The use of gamma radiation did not lead to improvement, regardless of the applied dose

Made available in DSpace on 2014-08-20T14:22:09Z (GMT). No. of bitstreams: 1 Tese_Juliana_Magalhaes_Bandeira.pdf: 1698906 bytes, checksum: 40fa28ef99ce7cee9d0955c4f8688cdf (MD5) Previous issue date: 2010-04-09 / The Japanese plum (Prunus salicina Lindl.) has an important role in the horticulture worldwide. It has great importance in Brazilian market and is gaining fans for its production, especially in Rio Grande do Sul and Santa Catarina where winter conditions are propicious to its cultivation. However, there are some problems faced by farmers and breeders, which limit the increase in domestic production of plum trees, among these, there are the gametophytic self-incompatibility, due to the presence of a codominant multi-site (containing the so-called S-alleles) and susceptibility to Xillela fastidiosa Wells, which affects quality of propagation material. In face of these problems, the objective of this work was to identify physiologically Salleles of six cultivars of Japanese plum and develop a micropropagation protocol for the cv. America. Thus, experiments of controlled pollination were carried out in experimental fields at Embrapa Clima Tempreado (Pelotas/RS) and the in vivo pollination were carried out in the laboratory of six cup cultivars of Japanese plum (America, Rosa Mineira, Pluma 7, Amarelinha, Reubennel and Santa Rosa), to evaluate the fruit set and pollen tube growth (CTP), respectively. Additionaly, were also performed experiments of micropropagation in the Laboratory of Plant Tissue Culture (UFPel/RS) to identify an appropriate protocol for micropropagation of cv. America. In studies of reproductive compatibility, the fruit set was very low for all crosses, with the larger value had occur in the autopollination of 'Reubennel' (8.41%). 'America' only formed fruit when pollinated with the cvs. Rosa Mineira, Amarelinha, Santa Rosa and Reubennel, these last one had mutual compatibility with cv. America. 'Amarelinha' and 'Rosa Mineira' proved to be compatible with the pollen of 'Rosa Mineira' and 'Reubennel'. There was significant interaction for CTP level and pollen used to pollinate each female parents, and the crosses between 'America' x 'Pluma 7' and 'Rosa Mineira' x 'Santa Rosa' were incompatible while cv. America is self-incompatible. Some crosses that showed no pollination and fruiting in the field, hit the egg (level 6) or ovary (level 5) during in vivo pollination, such as 'Reubennel' x 'Rosa Mineira', 'Rosa Mineira' and 'Amarelinha' x 'America' and 'Amarelinha' and 'Pluma 7', and 'Santa Rosa' x 'America'. These results, together with the molecular data of S-alleles, allow a better understanding of the reproductive biology of P. salicina. In the micropropagation experiments we found that the in vitro establishment of basal 11 explants of cv. America in MS medium is higher than the apical explants. BAP concentrations between 0.25 and 0.50mg dm-3 are more appropriate for the multiplication while MS medium supplemented with 1.0mg dm-3 GA3 and 2.0g dm-3 of vegetal charcoal is the most appropriate to in vitro elongation of their shoots. Half of concentration of salts and vitamins of MS medium with the addition of 1.0mg dm-3 of IBA is the most efficient for the in vitro rooting of Japanese plum, cv. America, during periods of less than 20 days, reaching 88% survival after 30 days of acclimatization. / A ameixeira japonesa (Prunus salicina Lindl.) tem papel de destaque na fruticultura mundial. Possui grande importância no mercado brasileiro e vem ganhando adeptos à sua produção, principalmente no Rio Grande do Sul e Santa Catarina onde as condições de inverno favorecem o seu cultivo. Porém, existem alguns problemas enfrentados pelos produtores e melhoristas que limitam o aumento da produção nacional de ameixeiras, entre esses, destacam-se a autoincompatibilidade gametofítica, devido à presença de um loco multialélico (contendo os denominados alelos-S) e a suscetibilidade à Xillela fastidiosa Wells, que afeta a qualidade do material propagativo. Frente a esses problemas, o objetivo da realização deste trabalho foi identificar fisiologicamente os alelos-S de seis cultivares de ameixeira japonesa e desenvolver um protocolo de micropropagação para a cv. América. Desta forma, foram realizados experimentos de polinização controlada nos campos experimentais da Embrapa Clima Temperado (Pelotas/RS) e polinização in vivo, em laboratório, de seis cultivares copa de ameixeira japonesa (América, Rosa Mineira, Pluma 7, Amarelinha, Reubennel e Santa Rosa), onde foram avaliados a frutificação efetiva e o crescimento do tubo polínico (CTP), respectivamente. Também foram realizados experimentos no Laboratório de Cultura de Tecidos de Plantas (UFPel/RS), visando identificar um protocolo adequado para a micropropagação da cv. América. Nos estudos de compatibilidade reprodutiva, a frutificação efetiva foi muito baixa para todos os cruzamentos, sendo observado maior valor na autopolinização da Reubennel (8,41%). América somente apresentou frutificação quando polinizada com as cvs. Rosa Mineira, Amarelinha, Santa Rosa e Reubennel, sendo que essa última apresentou compatibilidade mútua com a cv. América. Amarelinha e Rosa Mineira mostraram-se compatíveis com o pólen da Rosa Mineira e Reubennel . Houve interação significativa para o grau de CTP e o pólen utilizado para polinizar cada um dos genitores femininos, sendo que os cruzamentos entre América x Pluma 7 e Rosa Mineira x Santa Rosa foram incompatíveis enquanto que a cv. América apresentou-se autoincompatível. Alguns cruzamentos que não apresentaram polinização e frutificação no campo, atingiram o óvulo (grau 6) ou o ovário (grau 5) durante a polinização in vivo, tais como Reubennel x Rosa Mineira ; 9 Rosa Mineira e Amarelinha x América e Amarelinha e Pluma 7 , e Santa Rosa x América . Estes resultados, juntamente com os dados moleculares dos alelos-S, permitem um melhor entendimento a respeito da biologia reprodutiva de P. salicina. Nos experimentos de micropropagação verificou-se que o estabelecimento in vitro de explantes basais da cv. América em meio MS, é superior ao de explantes apicais. Concentrações de BAP entre 0,25 e 0,50mg dm-3 são mais adequadas para sua multiplicação enquanto que o meio MS suplementado com 1,0mg dm-3 de AG3 e 2,0g dm-3 de carvão vegetal é o mais adequado para o alongamento in vitro de suas brotações. A metade da concentração dos sais e vitaminas do meio MS com a adição de 1,0mg dm-3 de AIB é o mais eficiente para o enraizamento in vitro de brotações de ameixeira japonesa, cv. América, por períodos inferiores a 20 dias, atingindo 88% de sobrevivência após 30 dias de aclimatização.

Thesis (PhD(Agric) (Horticulture))--University of Stellenbosch, 2011. / Includes bibliography. / ENGLISH ABSTRACT: Plums with good taste, aroma and eating quality lead to repeat purchases and sustained demand. Taste includes non-volatile compounds, e.g. sugars and acids, and has been well researched to meet the consumers’ preferences. Plum aroma, however, has not enjoyed the same attention. Limited literature is available on the aroma of Japanese plums and none could be found on the effects of relatively long cold storage on the profiles. The main aim of this study is to investigate the changes in aroma compounds of Japanese plums throughout maturation and ripening and the effects of commercial cold storage regimes. Near infra-red (NIR) spectroscopy was also evaluated as a non-destructive method to determine plum quality parameters aimed at minimising sample variability. In Paper 1, NIR spectroscopy was used to develop prediction models for total soluble solid (TSS), total acidity (TA), sugar-to-acid ratio, firmness and weight in three cultivars (Pioneer, Laetitia and Angeleno) and a multi-cultivar model. Samples were collected for seven consecutive weeks and repeated over two seasons. TSS results showed excellent predictability (R2 = 0.817-0.955; RMSEP= 0.453-0.610 % Brix) but the TA models did not perform well. The sugar-to-acid ratio models had results comparable to that of TSS. Both the firmness and weight models had acceptable results. The models of ‘Pioneer’ and ‘Laetitia’ had a better predictability capacity than the ‘Angeleno’ model. Although the multi-cultivar models outperformed the single cultivar models on R2 values it had higher prediction errors. The robustness of all the TSS, TA and firmness models is high in terms of seasonality, range and cultivar. Papers 2 and 3, the main focus of the study, are concerned with the aroma profile dynamics of Japanese plums. HS-SPME was used in both papers to extract the aroma compounds followed by GC-TOFMS for separation and identification. In Paper 2, the aroma volatile compounds of three cultivars (Pioneer, Laetitia and Angeleno) were determined for a seven week period including samples from three maturity stages (immature, harvest and tree-ripe). A total of 35 compounds were identified of which ten were generic. Each cultivar had five unique compounds resulting in different aroma profiles for each of the maturity stages and distinct separation patterns using discriminant analysis. The study was extended in Paper 3 where the aroma volatile compounds of six cultivars (Pioneer, Sapphire, Laetitia, Songold, Larry Anne and Angeleno) and one plumcot (Flavor King) were determined at three functional stages (commercial harvest, tree-ripe fruit and cold stored fruit). A total of 62 compounds were identified and classified into three groups (‘unique’ (31), ‘generic’ (11) and ‘frequent’ (20)) based on their frequency of occurrence. The aroma profiles of ‘Larry Anne’ and ‘Flavor King’ are the most affected by cold storage conditions and ‘Pioneer’ appears to be the least affected. All the cultivars have significantly different aroma profiles at all three of the functional stages with ‘Sapphire’, ‘Larry Anne’ and ‘Flavor King’ showing the largest differences. ‘Flavor King’, a plumcot, presented a ripe aroma profile that was much diverged from that of the true plums. / AFRIKAANSE OPSOMMING: Pruime met ‘n goeie smaak, aroma en eetkwaliteit lei tot herhaalde verkope en volhoubare aanvraag. Smaak sluit die nie-vlugtige stowwe (suikers en sure) in en is goed nagevors om die verbruikersvoorkeure te bevredig. Pruim aroma het egter nie dieselfde aandag geniet nie. Daar is beperkte literatuur beskikbaar wat handel oor die aroma van Japanese pruime en geen kon gevind word oor die effekte van lang koelopberging op die aromaprofiele nie. Die hoof doel van hierdie studie is om die veranderinge in die aromatiese komponente van Japanese pruime te ondersoek tydens die volwassewording- en rypwordingsprosesse asook die effekte van kommersiele koelopberging. Naby infrarooi (NIR) spektroskopie is ook geevalueer as ‘n nie-destruktiewe manier om pruim kwaliteitsparameters te bepaal met die doel om monstervariasie te beperk. In Artikel 1 is NIR spektroskopie gebruik om voorspellingsmodelle vir totale oplosbare suikers (TOS), totale suur (TS), suiker-tot-suur verhouding, fermheid en gewig te bepaal in drie kultivars (Pioneer, Laetitia en Angeleno) asook ‘n multi-kultivar model. Monsters is vir sewe opeenvolgende weke versamel en herhaal oor twee seisoene. TOS resultate toon uitstekende voorspelbaarheid (R2 = 0.817-0.955; RMSEP= 0.453-0.610 % Brix) maar TS modelle het egter nie so goed gevaar nie. Die suiker-tot-suur verhoudingsmodelle se resultate was vergelykbaar met die van TOS. Beide die fermheid- en gewigsmodelle het aanvaarbare resultate opgelewer. Die modelle vir ‘Pioneer’ en ‘Laetitia’ het ‘n beter voorspelbaarheidskapasiteit getoon as die van ‘Angeleno’. Alhoewel die multi-kultivar model beter presteer het as die enkel kultivar modelle op die R2-waardes was daar meer voorspellingsfoute. Hoe robuustheid is gevind i.t.v. seisoene, datagrense en kultivar vir al die TOS, TA en fermheidsmodelle. Artikels 2 en 3, die fokuspunt van die studie, handel oor die dinamika van die aromaprofiel van Japanese pruime. HS-SPME is in beide artikels gebruik on die aromatiese verbindings te ekstraeer gevolg deur GCTOFMS vir skeiding en identifikasie. In Artikel 2 is die aromatiese stowwe van drie kultivars (Pioneer, Laetitia en Angeleno) bepaal vir sewe opeenvolgende weke en sluit monsters van drie volwassenheidsstadiums in (onvolwasse, oes en boom-rypgemaakte pruime). ‘n Totaal van 35 verbindings is geidentifiseer waarvan tien as generies beskou kan word. Elke kultivar het vyf unieke komponente gehad en het gelei tot verskillende aromaprofiele vir elk van die volwassenheidsstadiums en diverse skeidingspatrone tydens die gebruik van diskriminant analise. Die studie is uitgebrei in Artikel 3 waartydens die aromatiese vlugtige stowwe van ses kultivars (Pioneer, Sapphire, Laetitia, Songold, Larry Anne en Angeleno) en een plumcot (Flavor King) bepaal is tydens drie funksionele stadiums (oes, boom-rypgemaak en koelopgebergde pruime). ‘n Totaal van 62 verbindings is geidentifiseer en in drie groepe geklassifiseer (‘uniek’ (31), ‘generies’(11) en ‘gereeld’ (20)) gebaseer op voorkomsfrekwensie. Die aromaprofiele van ‘Larry Anne’ en ‘Flavor King’ is die meeste deur die koelopberging geaffekteer en ‘Pioneer’ die minste. Al die kultivars het kenmerkend verskil t.o.v. hul aromaprofiele in al drie die funksionele groepe en ‘Sapphire’, ‘Larry Anne’ en ‘Flavor King’ het die grootste verskille getoon. ‘Flavor King’, die plumcot, het ook ‘n ryp aromaprofiel gehad wat baie van die van die egte pruime verskil het.

Thesis (MSc Food Sc)--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: Nectar formulations containing red-fleshed plum pulp and varying amounts of red-fleshed plum skin extract were developed. Red-fleshed plum nectar formulations containing 0, 8, 16, 24, and 32% skin extract were benchmarked against twenty-two commercial beverages containing red, violet and blue fruits. The total soluble solid content, pH, titratable acidity, colour, total polyphenolic, individual polyphenolic, total anthocyanin, and ascorbic acid contents, as well as antioxidant activity (oxygen radical antioxidant capacity (ORAC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, and ferric reducing/antioxidant power (FRAP)) of the commercial beverages and plum formulations were determined. The plum nectar formulations had similar or higher total polyphenolic content, antioxidant activity, and colour values than the average for the commercial beverages. The individual polyphenolic compounds analysed in the nectar formulations were cyanidin-3-glucoside, cyanidin-3- rutinoside, quercetin-3-glucoside, quercetin-3-rutinoside, quercetin-3-xyloside, and neochlorogenic acid. Increasing polyphenolic content and antioxidant activity was observed with an increase in skin extract content of the formulations. The sensory attributes of the formulations were plum and plantlike aroma, plum and plantlike flavour, sweetness, acidity, and astringency. Increases in plantlike aroma and flavour, acidity, and astringency in conjunction with decreases in plum aroma, plum flavour, and sweetness extract were observed with an increase in skin extract. Consumer analysis indicated that all formulations were acceptable. The 0 and 16% skin extract formulations were most preferred, while the 32% skin extract formulation was least preferred. A shelf-life study was conducted in two phases. In Phase 1, the 0, 16 and 24% skin extract formulations were stored at 0 and 5°C (analysis time points: before pasteurisation, after pasteurisation (week 0), and after 1, 2, 4, 6, 8, 12, 16, 18, 20, and 24 weeks of storage). Chemical analyses conducted included colour, total polyphenolic, individual polyphenolic compound, and total anthocyanin contents, and antioxidant activity (DPPH• scavenging activity). Results from Phase 1 indicated close associations between the 16 and 24% skin extract formulations, and between these formulations and all chemical attributes. Regression analysis of results indicated significant (P 0.05) decreases in red colour, total anthocyanins, cyanidin-3-glucoside, cyanidin-3- rutinoside, DPPH• scavenging activity, total polyphenolic content, quercetin-3-rutinoside, and quercetin- 3-xyloside for formulations stored at 0°C. The total and red colour, total anthocyanins, cyanidin-3- glucoside, and cyanidin-3-rutinoside in formulations stored at 5°C showed similar results. During Phase 2 of the shelf life study, sensory analysis was conducted on the 0 and 24% skin extract formulations stored at 5°C (preparation time points: 0, 1, 2, and 3 months). Sensory attributes, including plum, plantlike, and raisin flavour, sweetness, acidity, and astringency, were stable during storage. Chemical results from Phase 2 were similar to those of Phase 1. The chemical and sensory stability of formulations after 24 weeks of storage in Phase 1 and Phase 2 indicated that, with the exception of the anthocyanin degradation, the formulations could be beneficial to juice industries. Thus, red-fleshed plum nectars have the potential to compete with high-antioxidant fruit beverages. / AFRIKAANSE OPSOMMING: Nektarformulasies wat rooivleis pruimpulp en varieërende hoeveelhede rooivleis pruimskilekstrak bevat, is ontwikkel en ondersoek. Rooivleis pruimnektarformulasies wat 0, 8, 16, 24, en 32% skilekstrak bevat, is vergelyk met twee-en-twintig kommersiële drankies wat rooi, violet en blou vrugte bevat. Die totale oplosbare vastestof, totale polifenoliese, individuele polifenoliese, totale antosianien- en askorbiensuur inhoude, sowel as die pH, titreerbare suurheid, kleur, antioksidant aktiwiteit (suurstofradikale antioksidantkapasiteit (ORAC), 2,2-difeniel-1-pikrielhidrasiel (DPPH) radikaal blussingsaktiwiteit, en ysterreduserende/antikoksidantkrag (FRAP)) van die kommersiële drankies en pruimnektarformulasies, is bepaal. Die pruimnektarformulasies het soortgelyke of hoër totale polifenoliese inhoud, antioksidantaktiwiteit, en kleurwaardes gehad in vergelyking met die gemiddelde vir die kommersiële drankies. Die individuele polifenoliese verbindings wat in die nektarformulasies geanaliseer is, was sianidien-3-glukosied, sianidien-3-rutinosied, kwersetien-3-glukosied, kwersetien-3-rutinosied, kwersetien-3-xylosied, en neochlorogeniese suur. ‘n Toenames in die kleurwaardes, polifenoliese inhoud, en antioksidantaktiwiteit is waargeneem met ‘n toename in skilekstrak is in die formulasies. Die sensoriese eienskappe van die formulasies was pruim- en plantagtige aroma, pruim- en plantagtige geur, soetheid, suurheid, en frankheid. Toenames in plantagtige aroma en geur, suurheid en frankheid, sowel as ‘n afname in pruimaroma, pruimgeur, en -soetheid, is met ‘n toename in skilekstrak waargeneem. Verbruikersanalise het aangedui dat al die formulasies aanvaarbaar was. Die 0 en 16% skilekstrakformulasies was die mees aanvaarbaarste, terwyl die 32% skilekstrakformulasie die minste aanvaarbaar geag is. ‘n Rakleeftydstudie is in twee fases gedoen. In Fase 1 is die 0, 16, en 24% skilekstrakformulasies by 0 en 5°C gestoor (analiseringstydpunte: voor pasturisasie, na pasturisasie (week 0), en na 1, 2, 4, 6, 8, 12, 16, 18, 20, en 24 weke van berging). Chemiese analise wat gedoen is, sluit totale polifenoliese, individuele polifenoliese verbinding, en totale antosianien inhoude, sowel as kleur en antioksidantaktiwiteit (DPPH• blussingsaktiwiteit) in. Resultate van Fase 1 het ‘n nou verband tussen die 16 en 24% skilekstrakformulasies, sowel as tussen hierdie formulasies en hul chemiese kenmerke aangedui. Regressie-analise van resultate het betekenisvolle (P 0.05) afnames geïllustreer in rooi kleurwaardes, DPPH• blussingsaktiwiteit, sowel as totale antosianiene, sianidien-3-glukosied, sianidien-3-rutinosied, totale polifenoliese, kwersetien-3-rutinosied, en kwersetien-3-xylosied inhoude van die formulasies wat by 0°C gestoor is. Die totale kleur-, rooi kleurwaardes, sowel as totale antosianien, sianidien-3-glukosied, en sianidien-3-rutinosied in die formulasies wat by 5°C gestoor is, het soortgelyke resultate gegee. Gedurend Fase 2 van die rakleeftydstudie is sensoriese analise op die 0 en 24% skilekstrakformulasies wat by 5°C gestoor is, gedoen (voorbereidingstydpunte: 0, 1, 2, en 3 maande). Sensoriese eienskappe, insluitend pruim-, plantagtige-, en rosyntjiesmake, soetheid, suurheid, en frankheid, was stabiel gedurende berging. Chemiese resultate van Fase 2 was soortgelyk aan dié van Fase 1. Die chemiese en sensoriese stabiliteit van die formulasies na 24 weke van opberging in Fase 1 en Fase 2 nieteenstaande antosianienafname, het aangedui dat die formulasies voordelig kan wees vir die vrugtedrankiebedryf. Dus het rooivleis pruimnektars die vermoeë om met hoë antioksidant vrugtedrankies mee te ding.

Orientador: Rogério Lopes Vieites / Banca: Regina Marta Evangelista / Banca: Ben Hur Mattiuz / Banca: Luciana Manoel / Banca : André José de Campos / Resumo: Este trabalho teve como objetivo prolongar a vida útil de ameixas cv. Gulfblaze, provenientes de Holambra II - SP, com o emprego da irradiação gama, embalagem e o uso de condicionamento térmico em frutos refrigerados. Foram realizados dois experimentos: Experimento 1 - frutos irradiados (0,0; 0,4; 0,6; 0,8; 1,0kGy) submetidos à atmosfera modificada passiva e Experimento 2 - frutos submetidos ao condicionamento térmico (10±2°C por 2 dias), irradiados (0,0; 0,4; 0,6; 0,8; 1,0kGy) submetidos à atmosfera modificada passiva. Os frutos foram selecionados e embalados para então serem irradiados no IPEN, localizado em São Paulo - SP. Logo após seguiram para o Laboratório de Frutas e Hortaliças, pertencente ao Departamento de Gestão e Tecnologia Agroindustrial, da Faculdade de Ciências Agronômicas - UNESP - Câmpus de Botucatu, SP. Nos dois experimentos, os frutos após os tratamentos, foram armazenados em B.O.D. a 0±2°C e com 90±5% de UR por 35 dias. As avaliações foram realizadas a cada cinco dias, durante 35 dias de armazenamento. As alterações na qualidade pós-colheita foram detectadas por meio das análises de perda de massa fresca, firmeza, pH, acidez titulável, sólidos solúveis, razão SS/AT "Ratio" açúcares redutores, açúcares totais, vitamina C total, pigmentos, compostos fenólicos totais e taxa de respiração. O delineamento estatístico empregado foi inteiramente casualizado com três repetições por tratamento para cada um dos oito tempos de avaliação, utilizando-se o Teste de Tukey a 5% de probabilidade. Nas condições em que os experimentos foram realizados, os resultados permitem concluir que, os frutos da ameixeira 'Gulfblaze' são resistentes à refrigeração (0±2°C), não apresentando sintomas de injúria até os 35 dias de armazenamento. O condicionamento levou a uma aceleração do amadurecimento, mostrando-se não recomendável para essa variedade de ameixas / Abstract: The present work aims at protracting the lifespan of plums cv. Gulfblaze, originating from Holambra II, São Paulo, by application of gamma irradiation, packaging and the use of thermal conditioning on cold fruits. Two experiments were made: Experiment 1. irradiated fruits (0,0; 0,4; 0,6; 0,8; 1,0KGy) undergo a passive modified atmosphere and Experiment 2. fruits undergo thermal conditioning (10±2°C for 2 days), irradiation (0,0; 0,4; 0,6; 0,8; 1,0KGy), and are subjected to passive modified atmosphere. The fruits were selected and packed, and then irradiated at IPEN, located in São Paulo - SP. Thereupon, they were directed to the Laboratory of Fruit and Vegetables from the Department of Management and Agribusiness Technology of the Agronomic Sciences Faculty - UNESP - Botucatu, Brazil. In both experiments, after the treatment the fruits were stored in B.O.D at 0±2°C with 90±5% RH for 35 days. Evaluations were conducted every five days, for the 35 days of storage. Alterations on post-harvest quality were detected by means of analysis of fresh mass loss, consistency (firmness), pH, total titratable acidity, soluble solids, 'Ratio' (SS/TTA), reducing sugar content, total reducing sugar, vitamin C total, pigment, phenolic compounds and respiratory rates. The employed statistical design was thoroughly randomized with three replications per treatment for each of the eight evaluations using the Turkey's Test to 5% of probability. Under the circumstances in which the experiments were performed, the results allow for the conclusion that 'Gulfblaze' plum fruits are resistant to refrigeration (0±2°C), with no symptoms of injury during the 35 days at storage. The conditioning led to ripening acceleration, proving to be not advisable for this sort of plum. The use of gamma radiation did not lead to improvement, regardless of the applied dose / Doutor