by Huanpu Jun. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1990. / Bibliography: leaves 122-136. / Acknowledgement --- p.iii / Abstract --- p.V / Introduction --- p.1 / Literatiure review --- p.3 / Chapter A. --- "The changes of fruit during development, maturation, senescence" --- p.3 / Chapter 1. --- Fruit --- p.3 / Chapter 2. --- Fruit cell --- p.6 / Chapter 3. --- Respiration and ethylene --- p.18 / Chapter 4. --- Other oxidative reaction --- p.21 / Chapter 5. --- Control of ripening --- p.22 / Chapter B. --- In period of harvest and storage --- p.23 / Chapter 1. --- After harvest --- p.24 / Chapter 2. --- Postharvest technology procedures --- p.25 / Chapter C. --- Litchi --- p.28 / Chapter 1. --- Morphology and embryology --- p.28 / Chapter 2. --- Composition --- p.30 / Material and methods --- p.33 / Chapter A. --- "Morphological , anatomical and physical studies" --- p.33 / Chapter B. --- Biochemi cal studiets --- p.34 / Chapter 1. --- Starch content --- p.34 / Chapter 2. --- Soluble protein content --- p.35 / Chapter 3. --- Sugar component separated by thin layer chromatography --- p.36 / Chapter 4. --- Reducing sugar content --- p.36 / Chapter 5. --- Total sugars --- p.37 / Chapter 6. --- Acid content --- p.37 / Chapter 7. --- Chlorophyll contents --- p.37 / Chapter 8. --- Anthocyanin contents --- p.38 / Chapter 9. --- Phenolic compound content --- p.33 / Chapter 10. --- Peroxidase activity --- p.39 / Chapter 11. --- Superoxide dismutase activity --- p.39 / Chapter 12. --- Vitamin C content --- p.40 / Chapter C. --- Preliminary study on storage --- p.41 / Results --- p.43 / Chapter A. --- Development period --- p.43 / Chapter 1. --- "Morphological , anatomical and physical changes" --- p.43 / Chapter i. --- Whole Fruit --- p.43 / Chapter ii. --- Seed --- p.43 / Chapter iii. --- Aril --- p.44 / Chapter 2. --- Rhysio1ogica1 and biochemical changes --- p.47 / Chapter i. --- Weight and water content --- p.47 / Chapter ii. --- Soluble protein content --- p.52 / Chapter iii. --- Starch content --- p.52 / Chapter iv. --- Acidity --- p.52 / Chapter v. --- Sugar content --- p.61 / Chapter vi. --- Change in pericarp --- p.68 / Chapter B. --- Storage period --- p.63 / Chapter 1. --- Fruit without any treatment stored at 5°C and 10°C --- p.63 / Chapter 2. --- Fruit was treated and packed with different methods and then stored at 10°C and room temperature respectively --- p.75 / Chapter i. --- Change in Fresh weight of stored Fruit --- p.75 / Chapter ii. --- Rate of rotting --- p.78 / Chapter iii. --- Rate of darkening --- p.78 / Chapter iv. --- Anthocyanin --- p.87 / Chapter v. --- Phenolic compound --- p.87 / Chapter vi. --- Chlorophyll --- p.88 / Chapter vii. --- Acidity --- p.88 / Chapter viii. --- Total sugar --- p.101 / Chapter ix. --- Reducing sugar --- p.101 / Chapter x. --- Ascorbic acid --- p.106 / Chapter xi. --- Peroxidase activity --- p.106 / Chapter xii. --- Superoxide dismutase --- p.107 / Discussion --- p.114 / Reference --- p.122

Thesis (MTech (Chemistry))--Cape Peninsula University of Technology, 2015. / It has recently been confirmed that people consuming 7+ portions of fruit and vegetables daily have a lower risk of mortality from any cause. With a fifth of the population of South Africa falling below the poverty line, it has been found that rural adults have a very low daily intake of fruit and vegetables; at the same time rural children are consuming a primarily maize-based diet. This low dietary diversity translates into a higher level of infectious diseases in children younger than five years. Interventions at national level included promoting the growing of underexploited traditional indigenous vegetables and fruits in home gardens, in the hope that rural households would help themselves in diversifying their cereal-based diet, while using crops they are accustomed to in their environment. Ten indigenous South African fruits found in the Western Cape were evaluated for their potential to make a positive contribution to the diet of rural communities and were compared with Blueberry and Cranberry, the North American ‘gold standards’. The following determinations were carried out on 12 samples: Total Phenolic Content, Total Flavanols and Total Monomeric Anthocyanins were analysed using the Folin-Ciocalteu, Mazza and pH Differential methods. Total Antioxidant Capacity was assessed using the Trolox Equivalent Antioxidant Capacity (TEAC), DPPH and Molybdenum Reduction assays. The Oxygen Radical Absorbance Capacity (ORACFL) was also determined. Iron Chelating Activity, one of the methods recommended to reflect other antioxidant mechanisms, was also investigated. The fruits possessing the highest concentration of Total Phenolic Content (Mazza) were Christmas berry, Bietou, Wild Olive and Wild Plum, at levels significantly higher than those of the two control berries, Blueberry and Cranberry. The fruits yielding the highest results for the TEAC assay were Wild Plum, Wild Olive, Tortoise berry, Christmas berry and Colpoon. The fruits giving the highest results for the DPPH assay were Wild Plum, Colpoon, Wild Olive, and Christmas berry. The fruits showing the highest results for the Molybdenum Reduction assay were Wild Olive, Wild Plum, Christmas berry, and Tortoise berry. The fruits yielding the highest results for the ORAC Total Antioxidant Capacity assay were Colpoon, Christmas berry, Wild Olive, Crossberry, Wild Plum, Waterberry followed by Blueberry and Cranberry. The results from the Iron Chelating Activity assay revealed a ranking of Christmas berry, Blueberry, followed by Num-num. On combining the results of eight assays, namely TPC (Mazza), TF, TA, TEAC, DPPH, TAC, TPC (FCR), ICA to give an Antioxidant Potency Composite Index, the fruits with the highest iv rankings were (1) Wild Plum, (2) Wild Olive, (3) Colpoon, and (4) Christmas berry. By comparison the northern hemisphere control berries ranked (5) Blueberry and (9) Cranberry. These findings show that by introducing even small servings of indigenous fruits into the diet, an important and inexpensive source of natural antioxidants could be accessed and the mean daily ORAC intake could thereby be boosted significantly by about 4,000 µmol Trolox Equivalents to bring the Total ORAC consumed to within optimum levels (6,000 µmol Trolox Equivalents and above). These bioactive plant compounds have the potential to deliver immense benefits to health to impoverished South African adults, as well as rural children, well beyond basic nutrition.

Made available in DSpace on 2017-03-14T14:10:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-09-29. Added 1 bitstream(s) on 2017-03-14T14:42:49Z : No. of bitstreams: 1 000879253.pdf: 882792 bytes, checksum: 526f01031b70001b5f864bbca746d50d (MD5) / Objetivou-se avaliar a influência de diferentes doses de irradiação ionizante com o 60Co nas características física, físico-químicas, químicas e bioquímicas em pós-colheita de frutos de pitaia orgânica da espécie Hylocereus undatus, cultivada na região de Itajobí - SP. O experimento foi conduzido no Laboratório de Frutas e Hortaliças do Departamento de Gestão e Tecnologia Agroindustrial - FCA e Laboratório de Química e Bioquímica do Departamento de Botânica - IBB /UNESP - Botucatu - SP no período de março a abril de 2010. O processo de radiação foi realizado no Instituto de Pesquisas Energéticas e Nucleares (IPEN) localizado em São Paulo. Os frutos foram colhidos no terceiro dia após o início da coloração, selecionados, lavados em água corrente, secos em papel toalha. Destes foram considerados para fins de caracterização sem a interferência da radiação e tempode armazenamento, 20 frutos formando 10 repetições compostos por dois frutos cada. Para constituição dos tratamentos, os frutos foram embalados em bandejas poliestireno expandido, revestidas por filme de PVC, pré - resfriados (8oC por 24 horas) e submetidos as diferentes doses de irradiação gama (0,0; 0,2; 0,4; 0,6; 0,8 e 1,0 kGy de cobalto-60) sendo posteriormente armazenados em câmara fria a temperatura de 8 ± 1oC, com 90 ± 5% UR. Os frutos foram avaliados quanto ao pH, sólidos solúveis (SS), acidez titulável (AT), ratio (SS/AT), perda de massa, atividade respiratória, firmeza, umidade, relação polpa casca, açúcares redutores, açúcar não redutor e açúcar total, compostos fenólicos, flavonóides, proteína, fibra, lipídeos e minerais no dia da colheita, para caracterização dos frutos e os resultados obtidos foram considerados como padrão. Após a aplicação das doses de irradiação ionizante os frutos foram avaliados nos tempos 0, 5º, 10º, 15º e 20º dias de armazenamento ... / This work's objective was to evaluate the influence of different dosages of ionizing irradiation with 60Co in physical, physico-chemical, biochemical and chemical characteristics in post-harvest pitaya organic fruit of the Hylocereus undatus species, grown in the region of Itajobi - SP. The experiment was conducted in the Fruit and Vegetable Laboratory, Department of Agribusiness Management and Technology - FCA and Laboratory of Chemistry and Biochemistry, Department of Botany - IBB / UNESP - Botucatu - SP from March to April 2010. The radiation process was carried out at the Institute of Energy and Nuclear Research (IPEN) located in Sao Paulo. The fruits were harvested on the third day after the onset of color, selected, washed in running water and dried on paper towels. 20 fruits were, then, chosen, forming two replications of 10 fruits each, for characterization purposes without the interference of radiation and storage time. For treatments procedures, the fruits were packed in styrofoam trays, covered with PVC film, pre - cooled (8 ± oC for 24 hours) and subjected to different dosages of gamma irradiation (0.0, 0.2, 0.4; 0.6, 0.8 and 1.0 kGy of cobalt-60), and were subsequently stored in cold temperature of 8 ± 1 °C, with 90 ± 5% R U. The fruits were evaluated for their pH, soluble solids (SS), titratable acidity (TA), ratio (SS / TA), weight loss, respiratory activity, firmness, moisture, peel pulp relation, reducing sugars, non-reducing sugar, total sugars, phenolic compounds, flavonoid, protein, fiber, lipids and minerals on the day of the harvest for characterization and the results obtained were regarded as standard. After application of ionizing irradiation dosages, the fruits were evaluated after 0, 5, 10, 15 and 20 days of storage at a temperature of 8 ± 1 ºC for their pH, soluble solids (SS), titratable acidity (TA), ratio (SS / TA), weight loss, respiration rate, firmness ...

Orientador: Rogério Lopes Vieites / Banca: Giuseppina Pace Pereira Lima / Banca: José Maria Monteiro Sigrist / Banca: Andre Jose de Campos / Banca: Luciana Manoel de Oliveira / Resumo: Objetivou-se avaliar a influência de diferentes doses de irradiação ionizante com o 60Co nas características física, físico-químicas, químicas e bioquímicas em pós-colheita de frutos de pitaia orgânica da espécie Hylocereus undatus, cultivada na região de Itajobí - SP. O experimento foi conduzido no Laboratório de Frutas e Hortaliças do Departamento de Gestão e Tecnologia Agroindustrial - FCA e Laboratório de Química e Bioquímica do Departamento de Botânica - IBB /UNESP - Botucatu - SP no período de março a abril de 2010. O processo de radiação foi realizado no Instituto de Pesquisas Energéticas e Nucleares (IPEN) localizado em São Paulo. Os frutos foram colhidos no terceiro dia após o início da coloração, selecionados, lavados em água corrente, secos em papel toalha. Destes foram considerados para fins de caracterização sem a interferência da radiação e tempode armazenamento, 20 frutos formando 10 repetições compostos por dois frutos cada. Para constituição dos tratamentos, os frutos foram embalados em bandejas poliestireno expandido, revestidas por filme de PVC, pré - resfriados (8oC por 24 horas) e submetidos as diferentes doses de irradiação gama (0,0; 0,2; 0,4; 0,6; 0,8 e 1,0 kGy de cobalto-60) sendo posteriormente armazenados em câmara fria a temperatura de 8 ± 1oC, com 90 ± 5% UR. Os frutos foram avaliados quanto ao pH, sólidos solúveis (SS), acidez titulável (AT), ratio (SS/AT), perda de massa, atividade respiratória, firmeza, umidade, relação polpa casca, açúcares redutores, açúcar não redutor e açúcar total, compostos fenólicos, flavonóides, proteína, fibra, lipídeos e minerais no dia da colheita, para caracterização dos frutos e os resultados obtidos foram considerados como padrão. Após a aplicação das doses de irradiação ionizante os frutos foram avaliados nos tempos 0, 5º, 10º, 15º e 20º dias de armazenamento ... / Abstract: This work's objective was to evaluate the influence of different dosages of ionizing irradiation with 60Co in physical, physico-chemical, biochemical and chemical characteristics in post-harvest pitaya organic fruit of the Hylocereus undatus species, grown in the region of Itajobi - SP. The experiment was conducted in the Fruit and Vegetable Laboratory, Department of Agribusiness Management and Technology - FCA and Laboratory of Chemistry and Biochemistry, Department of Botany - IBB / UNESP - Botucatu - SP from March to April 2010. The radiation process was carried out at the Institute of Energy and Nuclear Research (IPEN) located in Sao Paulo. The fruits were harvested on the third day after the onset of color, selected, washed in running water and dried on paper towels. 20 fruits were, then, chosen, forming two replications of 10 fruits each, for characterization purposes without the interference of radiation and storage time. For treatments procedures, the fruits were packed in styrofoam trays, covered with PVC film, pre - cooled (8 ± oC for 24 hours) and subjected to different dosages of gamma irradiation (0.0, 0.2, 0.4; 0.6, 0.8 and 1.0 kGy of cobalt-60), and were subsequently stored in cold temperature of 8 ± 1 °C, with 90 ± 5% R U. The fruits were evaluated for their pH, soluble solids (SS), titratable acidity (TA), ratio (SS / TA), weight loss, respiratory activity, firmness, moisture, peel pulp relation, reducing sugars, non-reducing sugar, total sugars, phenolic compounds, flavonoid, protein, fiber, lipids and minerals on the day of the harvest for characterization and the results obtained were regarded as standard. After application of ionizing irradiation dosages, the fruits were evaluated after 0, 5, 10, 15 and 20 days of storage at a temperature of 8 ± 1 ºC for their pH, soluble solids (SS), titratable acidity (TA), ratio (SS / TA), weight loss, respiration rate, firmness ... / Doutor

Thesis (MSc)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: Successful export of South African fresh fruit requires fruit of a high quality. Variable fruit quality within a consignment is detrimental to effective marketing of the product. The light microclimate under which the fruit develops is one of the factors that affect within-tree and between-tree variation in quality, maturity and yield. Light exposure effects on fruit quality at harvest and after commercial storage and ripening periods, as well as the physiological mechanisms of these responses to light exposure were studied. Increased exposure to light resulted in the development of typical sun leaf characteristics, with the associated increase in leaf nitrogen concentration and photosynthetic rates. Size and mass of 'Laetitia' plums and 'Cripps' Pink' apples increased with increasing exposure to light. Shade treatments were only started after the initial phase of cell / division was complete. Increased size of the fruit was likely due to the improved carbon balance of the exposed foliage and fruit from the end of cell division until harvest. The transpiration stream was higher in the more exposed foliage compared to the shaded parts of the canopy. This was supported by increased transpiration rates and decreased midday water potentials of exposed leaves. 'Songold' plums and 'Rosemarie' pears were also investigated in the first season, but results were not conclusive. Increased exposure to light was associated with advanced maturity of 'Laetitia' plums at harvest. Shaded fruit were able to attain a similar level of maturity as exposed fruit during storage and ripening periods. At harvest and after the storage and ripening periods, exposed fruit had a higher total soluble solid (TSS) content and therefore an improved eating quality. At harvest, blush colour of 'Laetitia' plums increased with increased exposure to irradiance. Blush colour continued to develop during storage and ripening, and after the ripening period it was evident that blush colour development was associated with a dosage effect i.e. exposure to a cumulative level of irradiance gives the fruit the potential to develop a certain amount of blush colour. Fruit exposed to more than 70% photosynthetic photon flux density (PPFD) were .able to develop to a similar level of blush colour, whereas, fruit exposed to less than 50% PPFD were not able to attain the same level of blush colour. Increased exposure to light did not result in advanced maturity of 'Cripps' Pink' apples at harvest, but it did lead to improved blush colour and increased TSS levels. Blush colour of 'Rosemarie' pears was also dependent on exposure to light from four weeks before harvest. Exposed 'Laetitia' plums had a greater whole fruit content of Mn and B, but concentration on a dry mass basis of P, K, and B decreased with increasing light. Exposed 'Cripps' Pink' apples had increased whole fruit content of P, K, Ca, Mg, Mn, Fe, Cu and B, but concentration on a dry mass basis of K and Na decreased with increasing light. Nutrient content is often associated with the incidence of internal disorders of fruit after storage and further investigation of this effect is necessary as internal disorders were virtually absent in this study. The termination of irrigation shortly before harvest in order to advance the maturity of all the fruit to a similar level, and the subsequent strip harvest of the fruit on a single harvest date, is a practice commonly used by South African plum producers to reduce cost and ostensibly to improve fruit quality. The effect of this practice on 'Songold' plum quality at harvest, after storage and after ripening was also studied. Drip-irrigated plums and plums subjected to soil drying had a better eating quality and were more marketable than micro-irrigated and non-droughted fruit. Following commercial storage and ripening periods these fruit were firmer, had a higher TSS content and were of a similar size and mass to micro-irrigated and non-droughted fruit. The extended harvesting period, in contrast to a strip harvest, allowed the fruit that were smaller and less mature at the beginning of the period to attain a greater size and advanced maturity toward the end of the harvesting period. / AFRIKAANSE OPSOMMING: Suksesvolle uitvoer van Suid-Afrikaanse vars vrugte vereis volgehoue hoë gehalte. Wisselvallige vruggehalte binne 'n besending is nadelig vir die effektiewe bemarking van die produk. Die lig mikroklimaat waaronder die vrug ontwikkel is een van die faktore wat variasie in gehalte, rypheidsstadium en opbrengs binne die boom en tussen bome beïnvloed. Die effek van verhoogde ligblootstelling op vruggehalte by oes, na kommersiële opberging en na die rypwordingsperiode, sowel as die fisiologiese meganismes van die reaksie van verhoogde ligblootstelling is bestudeer. Verhoogde blootstelling aan lig lei tot die ontwikkeling van tipiese son-blaar karaktertrekke, met die gepaardgaande verhoging in blaar stikstof konsentrasie en fotosintetiese tempo. Grote en massa van 'Laetitia' pruime en 'Cripps' Pink' appels het toegeneem met verhoogde blootstelling aan lig. Skadu behandelings is eers begin na die einde van die periode van selverdeling. Toenemende grootte van die vrugte is as gevolg van die verbeterde koolstofbalans van die blootgestelde blare en vrugte vanaffase II van vruggroei tot oestyd. Die transpirasie stroom is geallokeer na die blootgestelde blare. Dit word ondersteun deur die verhoogde transpirasie tempo en verminderde middag waterpotensiaal van die blootgestelde blare. 'Songold' pruime en 'Rosemarie' pere is ook bestudeer, maar die uitslae is nie so oortuigend nie. Toenemende blootstelling aan lig is geassosieer met gevorderde rypheid van 'Laetitia' by oes. Dit was moontlik vir skadu vrugte om dieselfde rypheidsvlak as blootgestelde vrugte te bereik, tydens die opberging en rypwording periodes. Teen oestyd en na opberging en rypwording, het blootgestelde vrugte 'n hoër suiker inhoud gehad en dus 'n hoër eetgehalte. Teen oestyd, het die bioskleur van die pruime toegeneem met toenemende blootstelling aan lig. Ontwikkeling van bloskleur het aangehou gedurende opberging en rypwording, en na die die rypwordings periode was dit duidelik dat bioskleur ontwikkeling met 'n dosis-effek geassosieer word, m.a.w. blootstelling aan 'n sekere opgestapelde vlak van lig gee die vrug die potensiaal om 'n sekere hoeveelheid bioskleur te ontwikkel. Vrugte wat meer as 70% ligblootstelling gekry het, het dieselfde bioskleur ontwikkel, maar vrugte wat minder as 50% ligblootstelling gekry het, het minder bloskleur ontwikkel. Toenemende blootstelling aan lig het nie gelei tot gevorderde rypheid van 'Cripps' Pink' appels teen oestyd nie, maar dit het wel gelei tot verbeterde bioskleur en verhoogde suiker inhoud. Bloskleur van 'Rosemarie' pere is afhanklik van blootstelling aan lig kort voor oestyd. Blootgestelde 'Laetitia' pruime het 'n verhoogde vrug inhoud van Mn en B met verhoogde ligblootstelling gehad, maar die konsentrasie van P, K en B op 'n droë massa basis het afgeneem met verhoogde ligblootstelling. Blootgestelde 'Cripps' Pink' appels het 'n verhoogde vrug inhoud van P, K, Ca, Mg, Mn, Fe, Cu en B met verhoogde ligblootstelling gehad, maar die konsentrasie van K en Na op 'n droë massa basis het afgeneem met verhoogde ligblootstelling. Voedingstof inhoud is geassosieer met die voorkoms van interne probleme in vrugte na opberging en verdere navorsing oor hierdie effek is nodig. Die terminering van besproeiing kort voor oestyd met die doelom die rypheid van al die vrugte op dieselfde vlak te kry sowel as die gepaardgaande oes van al die vrugte op een dag, is 'n algemene praktyke wat gebruik word deur Suid-Afrikaanse pruim produsente om kostes te beperk en oënskynlik, om vruggehalte te verbeter. Die effek van hierdie praktyke op 'Songold' pruim gehalte teen oestyd, na opberging en na rypwording is ook bestudeer. Drup-besproeide pruime en pruime wat blootgestel is aan grond uitdroging het 'n beter eetgehalte en is meer bemarkbaar as mikro-besproeide en nie-droogte geïnduseerde vrugte. Na kommersiële opberging en rypwording periodes het hierdie vrugte 'n hoër fermheid en suiker inhoud gehad, en 'n gelyksoortige grootte en massa as mikrobesproeide en nie-droogte geïnduseerde vrugte. Die verlengde oesperiode het die kleiner en minder ryp vrugte aan die begin van die periode 'n kans gegee om toe te neem in grootte en 'n gevorderde vlak van rypheid te bereik aan die einde van die oesperiode.

The growth and yield response of strawberry (Fragaria X annassa Duch.) and cranberry (Vaccinium macrocarpon Ait) to various growth inhibitors, but especially to paclobutrazol (PP333), and fertilizers were investigated in glasshouse and field studies. PP333 decreased vegetative growth in a rate-dependent manner in both strawberry and cranberry. PP333 delayed fruit ripening in strawberry and decreased fruit set and fruit size in cranberry. PP333 decreased pollen germination of strawberry. Soil residues of PP333 were biologically active when measured 11 weeks after application in the strawberry study and when measured after 50 weeks in a cranberry study. In a field study with cranberry, PP333 caused a decrease in vegetative growth and an increase in flowering in the next season after treatment. Two-dimensional partitioning was used to account for yield variation from treatment effects on adjusted yield variates. The truss number was the most important contributor to yield variation in the strawberry, but was not affected by treatments. PP333 made a substantial contribution to yield variation in strawberry through its effect on fruit development and ripening. In the cranberry, fruit set was the major contributor to yield variation and PP333 influenced yield substantially through its effect on fruit set. In glasshouse studies, PP333 decreased shoot elongation in cranberry within 3 weeks of application, and increased the number of branches on primary shoots. Buds were formed within 7 weeks of treatment and some of the buds contained flowers. Shoot growth was greater with a high rate of NPK fertilizer than with the low fertilizer rate and was greater in peaty soil than in sandy soil. While bud set was not modified by soil type or fertilizer rate, high NPK fertilizer decreased floral induction. Some effects of PP333 treatment were decreased by gibberellic acid, but generally these effects here not reversed. In a field study with the cranberry, PP333 increased flower bud set for flowering and non-flowering uprights but slightly decreased floral induction for non-flowering uprights. / Land and Food Systems, Faculty of / Graduate

Made available in DSpace on 2016-12-08T16:44:52Z (GMT). No. of bitstreams: 1 Dissertacao CLARICE.pdf: 350421 bytes, checksum: a2dcc42e1ff13c1ca8967355f5c0db70 (MD5) Previous issue date: 2006-02-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The jelly palm tree ( butiazeiro ) belongs to the Arecaceae (=Palmae) family and produces fruits of small size, round shape, succulents and with yellow color at the maturity. However, the information about forms of fruit utilization and conservation for in natura consumption is scarce. This work was carried out to assess the effects of maturity stage at harvest, storage temperature, cooling delay, and modified atmosphere conditions on postharvest physiology and quality preservation of jelly palm fruits. The fruits were harvested at three maturity stages (green, yellow-green, and yellow) and stored at 0 and 20oC. Fruits stored at 0oC showed better retention of firmness, green color of the skin, total titratable acidity (TTA), and total soluble solids (TSS) than fruits stored at 20ºC. Fruits harvested at the green maturity stage showed the best benefit from cold storage, despite of its poorest sensorial quality, characterized by the higher values of TTA and lower values of TSS than fruits harvested at yellow-green and yellow maturity stages. Along the entire storage period, the fruits did not produce detectable levels of ethylene and they did not exhibit a climacteric respiratory pattern. Fruits harvested at different maturity stages did not show significant difference in terms of respiration rates. The respiration rates increased from 890 to 11,650 nmol of CO2 kg-1 s-1 with the increase of temperature from 0 to 30oC. This respiratory increase followed a sigmoid model, with a rapid increase between 0 and 10oC, and a more modest increase towards the temperature of 30oC. There was a positive effect of immediate cooling after harvest on fruit retention of firmness, skin green color, and TTA, but not on TSS. The results showed that jelly palm fruits are highly perishable, characterized by very high respiration rates. Therefore, fruit should be harvested at the yellow-green maturity stage and then immediately stored at 0oC to preserve its postharvest quality. Jelly palm fruits were harvested at the green (> 75% of skin surface with green color) and yellowgreen (with 25 to 75% of skin surface with green color) maturity stages and then stored at 0, 5, 10, 20, and 30oC. These fruits were subjectivelly assessed in terms of rot incidence, skin browning, shrinkage and total losses during the storage. The largest losses were recorded in fruits stored at 20 and 30oC, at both maturity stages. There was no significant difference in terms of fruit visual quality between the storage temperatures of 0, 5, and 10oC. Fruits harvested at the green maturity stage showed higher levels of skin browning and shrinkage, and lower levels rotting, than fruits harvested at the yellow-green maturity stage, specially when stored at 20 and 30oC. At the temperatures of 0 to 10oC, the fruits remained viable for consumption even at 31 days storage, showing the importance of fruit refrigeration. Jelly palm fruits harvested at the yellow-green maturity stage (with 25 to 75% of skin surface with green color) were packed under modified atmosphere condition with polyvinyl chloride (PVC), polyethylene (PE), and polyethylene sealed with vacuum (PE+vacuum), in addition to the control treatment (without film), and stored at 0-2ºC. Fruits packed in PE (with or without vacuum) showed the smallest fresh mass loss and the best postharvest quality preservation during cold storage, followed by fruits packed in PVC. The results show that jelly palm fruits should be harvested at the yellow-green maturity stage, and then cold stored (at about 0oC), under modified atmosphere conditions, by using PE films, to achieve the best preservation its postharvest quality. / O butiazeiro pertence à família Arecaceae (=Palmae), se caracteriza por apresentar frutos de tamanho reduzido, globosos, suculentos e epicarpo amarelado na maturidade. No entanto, pouco se conhece sobre as formas de utilização e conservação dos frutos de butiá para consumo in natura. O presente trabalho objetivou avaliar os efeitos do estádio de maturação, da temperatura de armazenamento, do tempo para o resfriamento e das condições de atmosfera modificada sobre a fisiologia e preservação da qualidade pós-colheita de frutos de butiá. Os frutos foram colhidos em três estádios de maturação (verde, verde-amarelo e amarelo) e armazenados a 0 e 20oC. Frutos armazenados a 0oC apresentaram melhor retenção de firmeza, de cor verde da epiderme, de acidez titulável total (ATT) e de sólidos solúveis totais (SST), em relação a frutos armazenados a 20oC. Os benefícios da refrigeração foram maiores para frutos colhidos em estádio verde, apesar da sua qualidade inferior, caracterizada pelos altos valores de ATT e baixos valores de SST em relação a frutos colhidos nos estádios verde-amarelo e amarelo. Durante todo o período de armazenamento não foi possível detectar etileno e observar a ocorrência de climatério respiratório. Não houve diferença significativa nas taxas respiratórias em pós-colheita entre os estádios de maturação dos frutos na colheita. Houve um aumento nas taxas respiratórias de 890 a 11.650 nmol de CO2 kg-1 s-1, com o incremento da temperatura de 0 a 30oC, segundo um modelo sigmoidal, ou seja, um rápido incremento nas temperaturas entre 0 a 10oC, seguido de um aumento gradual tendendo a um equilíbrio na temperatura de 30oC. Houve efeito positivo da redução do tempo para refrigeração na preservação da firmeza, da cor verde da epiderme e da ATT, mas não dos teores de SST. Os resultados obtidos mostram que frutos de butiá apresentam alta perecibilidade, caracterizada pelas elevadas taxas respiratórias, sendo necessário o imediato resfriamento a 0oC, de frutos colhidos no estádio de maturação verde-amarelo, visando preservar a sua qualidade pós-colheita. Butiás colhidos nos estádios de maturação verde (> 75% de cor verde da epiderme) e verde-amarelo (com 25 a 75% de cor verde da epiderme) foram armazenados a 0, 5, 10, 20 e 30oC e avaliados de maneira subjetiva quanto a incidência de podridões, escurecimento da epiderme, frutos desidratados e perdas totais durante o armazenamento. As maiores perdas ocorreram em frutos armazenados a 20 e 30oC, para os dois estádios de maturação, não sendo observadas diferenças significativas entre as temperaturas de 0, 5 e 10oC. Frutos colhidos no estádio de maturação verde apresentaram maior escurecimento e desidratação, porém menores níveis de podridões, em relação a frutos colhidos no estádio verde-amarelo, especialmente quando armazenados nas temperaturas de 20 e 30oC. Nas temperaturas de 0 a 10oC, os frutos permaneceram viáveis por até 31 dias, demonstrando a importância da refrigeração. Butiás colhidos no estádio de maturação verde-amarelo (com 25 a 75% de cor verde da epiderme) foram acondicionados em condições de atmosfera modificada, com embalagens de policloreto de vinila (PVC), de polietileno (PE) e de PE selado a vácuo (PE+vácuo), além do tratamento controle (sem embalagem), e armazenados a 0-2ºC. A menor perda de massa fresca e a maior preservação da qualidade pós-colheita de butiá durante o armazenamento refrigerado foi observada com a utilização de PE, com ou sem vácuo, seguido do PVC. Os resultados obtidos demonstram a importância da colheita dos frutos no estádio de maturação verde-amarelo, e do seu armazenamento refrigerado (a temperaturas próximas de 0oC), em condições de atmosfera modificada, através da utilização de filmes de PE, na preservação da qualidade pós-colheita de butiás.

The South African fresh fruit industry is a significant exporter, accounting for approximately 45% of the country’s agricultural exports. Of the total exported fruit in the 2005/06 season, 60% was subtropical fruit. However, certain physiological rind disorders such as mango lenticel damage and citrus rind pitting are frequently observed, reducing the commercial value of the fruit. This thesis deals with the epidemiology of these rind physiological disorders, in an attempt to obtain basic information that could serve as a guideline to predict and manage the fruit susceptibility to these disorders. The study further investigated the relative effects that certain pre-harvest factors have on the postharvest development of these disorders. Factors of particular interest were harvest maturity, climate and the mineral content of the fruit. Rind pitting is a physiological disorder of citrus that develops during storage. A study was conducted to investigate the relative effects that certain pre-harvest factors have on the post-harvest development of superficial rind pitting in ‘Benny Valencia’ oranges. Factors of particular interest were harvest maturity, climate and the mineral content of the fruit. In addition, trees were treated with two different formulations of nitrogen viz. limestone ammonium nitrate (LAN) and a slow release nitrogen fertilizer (Horticote®), during March 2006. The fruit were then sampled on a two-weekly basis over a period of three months. On each sampling date a set of quality related readings, such as juice sugar and titratable acid concentration were taken, after which the mineral concentration of the exocarp and mesocarp was measured. Fruit were also stored under export simulation conditions. The results indicate that fruit from trees that received additional N were more susceptible to rind pitting than those from control trees. Of the two N applications, fruit from trees that received slow release N were more susceptible to rind pitting than fruit from trees that received the LAN treatment. Another important observation made was that the nitrogen concentration of oranges from trees that received extra nitrogen fertilizer was lower than that from the controls. In addition, experimental fruit were smaller than control fruit. Fruit from trees that received the slow release nitrogen treatment were smallest. A sink/source hypothesis aimed at explaining this phenomenon has been formulated and is currently being investigated. A number of control mechanisms are also being explored. Mango lenticel damage is a serious defect that occurs on the rind of the fruit. This condition causes fruit to attain a speckled appearance and become unattractive to the buyer. Each season, the disorder reduces the packout of fresh fruit by about 16%. Several preharvest factors play a critical role in the postharvest development of lenticel damage. Preliminary studies have shown that the incidence of lenticel damage has some relationship to fruit moisture and fruit nutrient concentration, depending on which of these factors first achieve a critical threshold. A study was conducted to develop appropriate skin moisture content parameters to predict lenticel damage potential before harvest. The study further aimed to provide certain biological markers regarding appropriate nitrogen fertilization practices to reduce lenticel damage. To do this, two trials were conducted approximately a month before harvest. Firstly, a plastic ground cover to restrict water supply was laid under ‘Tommy Atkins’ trees at Numbi Estates in the Hazyview area of the Mpumalanga province, South Africa. Secondly, additional nitrogen was applied as three different formulations, viz. limestone ammonium nitrate (LAN), potassium nitrate (KNO3), and a slow release nitrogen fertilizer under trade name Horticote®, to two ‘Tommy Atkins’ and two ‘Keitt’ orchards at Bavaria Estates in the Hoedspruit area of the Limpopo province, South Africa. Fruit samples were harvested, packed and stored at different intervals after rain during January 2006. With regard to lenticel damage on ’Tommy Atkins’ fruit from Numbi, there was no significant difference between the control and plastic cover treatments. However, when compared to fruit from other localities, the Numbi fruit had the highest incidence of lenticel damage, followed by the conventional orchard at Bavaria. The Numbi fruit, which had the highest incidence of lenticel damage, also had the highest pulp and skin nitrogen concentration. Of the four treatments at Bavaria, the LAN treatment had the highest incidence of lenticel damage, but the pulp and skin nitrogen concentrations of this treatment were comparable with the other treatments. The organic fruit had significantly lower lenticel damage incidence and also had the lowest pulp and rind nitrogen concentrations. Similarly, ‘Keitt’ results showed that the intensity of lenticel damage was significantly higher in the orchard that received additional nitrogen in the form of LAN. From the results it was, however, not possible to formulate nitrogen-lenticel damage correlations. The study failed to prove the case for a direct relationship between the disorder and with nitrogen, as there were no significant or consistent correlations with nitrogen content. An interesting relationship was nevertheless observed between lenticel damage and the time of harvest before and after rainfall. The results indicated that both ‘Tommy Atkins’ and ‘Keitt’ fruit become more susceptible to lenticel damage when harvested a day after rainfall and this gradually reduces afterwards. The effect of rainfall in this regard and a sink-source hypothesis arising from these observations are also discussed. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.