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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Mango (Mangifera indica L.) kernel fat : fatty acid profile, oxidative stability and development of fourier transform near infrared (FT-NIR) spectroscopy calibration models

Schoeman, Mathilda Elizabeth 12 1900 (has links)
Thesis (MSc Food Sc )--Stellenbosch University, 2002. / ENGLISH ABSTRACT: The oxidative stability of crude, cold-pressed mango kernel fat (MKF) was determined over a period of 240 days using the peroxide value (PV), conjugated diene value (CD) and p-anisidine value (AV) tests. The changes in fatty acid profile were monitored with gas chromatography and the oxidative status of MKF effectively predicted by FT-NIR spectroscopy. Results obtained from the different methods complemented each other and indicated the stable character of mango kernel fat against oxidative deterioration. The fatty acid profile constituted palmitic acid (CI6:0; 8.43%), stearic acid (CI8:0; 34.98%), oleic acid (CI8:1 cis; 48.05%), linoleic acid (CI8:2; 6.60%) and arachidic acid (C20:0; 1.73%). Trace amounts of C16:1 (0.56%), C18:1 trans (0.25%), C18:3 (0.43%), C20:1 (0.25%) and C22:0 (0.40%) were also found. The freshly pressed MKF had a peroxide value of 2.7 meq.kg", CD value of 0.07% and an AV of 2.2 mmol.kg", After 40 days of storage, the peroxide values of MKF stored with and without exposure to a limited amount of oxygen at 5, 15,25 and 40°C increased to 5 meq.kg" and 4 meq.kg" respectively. Emulsification of MKF had a stabilising effect (maximum PV = 2.8 meq.kg'), while exposure to UV light had a catalysing effect (maximum PV = 5 meq.kg'). These maximum values, decreased after 40 days. The CD values of MKF samples stored with and without exposure to oxygen at 5, 15,25 and 40°C increased to 0.18% and 0.16%, respectively at day 40. The CD values of samples exposed to light increased to 0_20% and the emulsified samples showed similar values to that of the MKF samples not exposed to oxygen. The conjugated diene values remained stable after day 40. The p-anisidine values of the MKF samples both stored with and without exposure to oxygen at 5, 15, 25 and 40°C varied between 0.5 and 5 mmol.kg". The weak correlation to the measurement of nonanal, as well as the low levels of 2-alkenals produced by the MKF, resulted in these low and sometimes non-linear values. The peroxide, conjugated diene and p-anisidine values obtained for MKF stored at 25°C over 240 days were low due to the low content of polyunsaturated fatty acids in MKF. This compared favourably with the higher values attained for sunflower, canola and olive oil, which are all rich in polyunsaturated fatty acids. The minimal changes observed in the fatty acid profile of mango kernel fat indicated the stability of the saturated fatty acids (CI6:0 and CI8:0) and oleic acid. In addition, the instability of linoleic and linolenic acids was evident due to oxidative deterioration. A decrease of 7.41% and 12.80% was observed between day 0 and 240 for the C18:2/C16:0 and C18:2/C18:0 ratios respectively. The prediction of the oxidative status of the MKF samples by near infrared spectroscopy were possible after the development of calibration models from a total data set of 300 samples of which one-third was used for independent validation. Principle component analysis (PCA) indicated classification at 0, 40 and the remaining (80 - 240) days. The best calibration model for PV yielded a SEP (standard error of prediction) of 0.46 meq.kg", correlation coefficient (r) of 0.95, bias of 0.02 and a root mean square error of prediction (RMSEP) of 0.46 meq.kg". The CD calibration model had a correlation coefficient of 0.89, SEP of 0.01 %, bias of 0.001 and RMSEP of 0.01% when developed on a data set with no pre-processing applied. The AV calibration had a SEP of 0.32 mmol.kg", bias of 0.03, RMSEP of 0.32 mmol.kg" and rof 0.93. The C18:2 and C18:3 models were built using partial least squares (PLS) regression and the values obtained for SEP were 0.31% and 0.054%, RMSEP 0.32% and 0.05%, bias 0.05 and 0.01 and correlation coefficcients were 0.82 and 0.54 respectively. The calibrations for CI8:1, C18:0 and C16:0 yielded weaker correlations. Good correlations were obtained when calibrating the CI8:2/CI6:0 and C18:2/CI8:0 ratios. / AFRIKAANSE OPSOMMING: Die oksidatiewe stabiliteit van ru, koud-geperste mango kern vet (MKV) (Mangifera indica L.) is oor 'n periode van 240 dae bepaal deur gebruik te maak van die peroksiedwaarde (PV), gekonjugeerde dieen waarde (CD) en p-anisidien waarde (AV) toetse. Die veranderinge in die vetsuurprofiel is gemonitor deur gaschromatografie en die oksidatiewe status van MKV is akkuraat voorspel word deur Fourier transformasie naby infrarooi (FT-NIR) spektroskopie. Die resultate van die verskillende toetsmetodes komplementeer mekaar goed en dui die stabiliteit van mango kern vet teen oksidatiewe verval aan. Die vetsuurprofiel is saamgestel uit palimitiensuur (C16:0; 8.43%), steariensuur (C18:0; 34.98%), oleïensuur (C18:1 cis; 48.05%), linoleïensuur (C18:2; 6.60%) en aragiedsuur (20:0; 1.73%). Spoorhoeveelhede C16:1 (0.56%), C18:1 trans (0.25%), C18:3 (0.43%), C20:1 (0.25%) en C22:0 (0.40%) is ook geïdentifiseer. Die vars geperste MKF het 'n peroksiedwaarde van 2.7 meq.kg", 'n CD waarde van 0.07% en 'n AV waarde van 2.2 mmol.kg" getoon. Na afloop van 40 dae opbergingsperiode by 5, 15, 25 en 40°C het die PV van MKV met 'n beperkte blootstelling aan suurstof na 5 meq.kg" vermeerder, terwyl die waardes van monsters sonder suurstofblootstelling na 4 meq.kg" vermeerder het. Emulsifisering van MKV het 'n stabiliserende effek (maksimum PV = 2.8 meq.kg") terwyl blootstelling aan ultraviolet (UV) lig 'n kataliserende effek (maksimum PV = meq.kgl ) op oksidasie gehad het. Hierdie maksimum waardes het na 40 dae afgeneem. Die CD waardes van MKF monsters opgeberg by 5, 15, 25 en 40°C en met beperkte blootstelling aan suurstof het vermeerder tot 0.18% terwyl die monsters sonder suurstofblootstelling by bogenoemde temperature vermeerder het tot 0.16% na 40 dae. Die gekonjugeerde dieen waardes van die monsters blootgestel aan UV lig het vermeerder tot 0.20%; terwyl die geëmulsifiseerde monsters waardes soortgelyk aan die MKV monsters sonder blootstelling aan suurstof getoon het. Gekonjugeerde dieen waardes het gestabiliseer vanaf dag 40. Die p-anisidienwaardes van MKV monsters opgeberg by temperature van 5,15, 25 en 40°C, met en sonder blootstelling aan suurstof, het varieer tussen 0.5 en 5 mmol.kg". Die swak korrellasie tussen nonanal produksie en p-anisidienwaardes, sowel as die klein hoeveelhede 2-alkenale geproduseer, was verantwoordelik vir hierdie lae en nie linêere waardes. Die peroksied, gekonjugeerde dieen en p-anisidienwaardes wat verkry is nadat MKV by 25°C in 240 opgeberg is, was laag weens die klein persentasie poli-onversadigde vetsure teenwoordig in die vet. Dit vergelyk goed met die hoë waardes wat verkry is vir sonneblom-, canola- en olyfolie wat almal ryk aan poli-onversadigde vetsure is. Die minimale veranderinge in die vetsuurprofiel van MKF dui op die stabiliserende invloed van versadigde vetsure (C16:0 en C18:0) en oleïensuur. Die onstabiliteit van linoleïen- en lineensuur duidelik uit hierdie vetsure se oksidatiewe verval. 'n Afname van 7.41% en 12.80% is waargeneem tussen dae 0 en 240 vir die C18:2/C16:0 en C18:2/C18:0 verhoudings, onderskeidelik. Die voorspelling van die oksidatiewe status van die MKF monsters met behulp van FT-NIR spektroskopie was moontlik deur die ontwikkeling van kalibrasie modelle. 'n Totale datastel van 300 monsters, waarvan ongeveer 'n derde vir validasie aangewend is, is gebruik vir die kalibrasiemodelle. Met behulp van PCA (hoojkomponent analise) kon drie klassifiseerbare groepe by 0, 40 en 80-240 dae onderskei word. Die beste kalibrasiemodel vir PV het 'n standaardfout van voorspelling (SEP) van 0.46 meq.kg", 'n korrellasiekoëffisient (r) van 0.95, 'n oorhelling van 0.02 en 'n standaardfout van voorspelling (RMSEP) van 0.46 meq.kg" gehad. Die CD kalibrasiemodel (geen voorafverwerking) het 'n r van 0.89, SEP van 0.01% oorhelling van 0.001 en RMSEP van 0.01% gehad. Die AV kalibrasie het 'n SEP van 0.32 mmol.kg', oorhelling van 0.03, RMSEP van 0.32 mmol.kg" en r van 0.93 gehad. Die C18:2 en C18:3 modelle is saamgestel deur PLS (partial least squares) regressie. Waardes verkry vir C18:2 en C18:3 was onderskeidelik: SEP 0.32% en 0.05%, RMSEP, 0.32% en 0.05%, oorhelling 0.05 en 0.01 en r 0.82 en 0.54. In die geval van C18:1, C18:0 en C16:0, het die kalibrasies swakker statistiek korrellasies getoon. Goeie korrellasies is verkry tydens kalibrasie vir die C18:2/C16:0 en C18:2/C18:0 verhoudings.
42

Otimização das condições de armazenamento sob atmosfera controlada de mangas 'Palmer' destinadas à exportação /

Santos Neto, João Paixão dos. January 2018 (has links)
Orientador: Gustavo Henrique de Almeida Teixeira / Coorientadora: Priscila Lupino Gratão / Banca: José Fernando Durigan / Banca: Marcos David Ferreira / Banca: Luciana Maria Saran / Banca: Eduardo Purgatto / Resumo: O objetivo geral deste trabalho foi conservar a qualidade de mangas 'Palmer' exportadas para a Europa e por objetivos específicos: I. estabelecer o melhor estádio de maturação para o transporte marítimo refrigerado e sob condições de atmosfera controlada (CA) determinado usando técnicas não-destrutivas de espectroscopia de infravermelho próximo (NIRS); II. desenvolver modelos de calibração e predição de matéria-seca (MS) e sólidos solúveis (SSC); III. comparar se a abordagem proposta difere do manuseio tradicional de mangas em uma remessa de mangas por frete marítimo para a Europa. No trabalho sobre a determinação dos índices de maturidade de manga 'Palmer' utilizando espectrômetro portátil de infravermelho próximo (VIS-NIR) o melhor modelo de calibração para SSC foi obtido usando espectros pré-processados com variação normal padrão (SNV), primeira derivada de Savitizk-Golay e janela de 699-999 nm. Para os SSC, foi observado um RMSECV de 1,39 % com um R2CV de 0,87 e RPD de 2,77. Melhores resultados foram observados para o modelo de calibração de MS construído com espectros em bruto usando a janela de 699-981 nm (RMSECV de 8,81 g.kg-1, R2CV de 0,84 e RPD de 2,51) e os modelos de calibração para firmeza foram considerados ruins. No estudo sobre armazenamento refrigerado de mangas 'Palmer' classificadas com base no teor de MS usando espectrômetro portátil de infravermelho próximo (VIS-NIR) foi possível concluir que o modelo PLS desenvolvido com as mangas da safra 2015/2016 não f... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The main objective of this study was to preserve the quality of 'Palmer' mangoes exported for the supply chain in Europe, and the specific objectives were: I. establish the best maturity stage for sea freight transportation and under controlled atmosphere (CA) conditions, determined using non-destructive of techniques near infrared spectroscopy; II. develop calibration and prediction models for dry matter (DM) and soluble solids content (SSC), III. compare if the proposed approach differs from the traditional mango handling to sea freight to Europe. In the study about the determination of the 'Palmer' mangoes maturity stages using near portable infrared spectrometer (VIS-NIR), the best calibration model for SSC was obtained using NIR spectra pre-processed with standard normal variation (SNV), first derivative of Savitizk-Golay, and 699-999 nm window. For SSC, it was observed a RMSECV of 1.39 %, with a R2CV of 0.87, and a RPD of 2.77. Better results could be seen for the DM calibration model built with raw spectra using the 699-981 nm window (RMSECV of 8.81 g.kg-1, R2CV of 0.84 and RPD of 2.51), and poor calibration models were obtained for firmness. In the study about refrigerated storage of 'Palmer' mangos sorted based on their DM content using near portable infrared spectrometer (VIS-NIR), it could be seen that the PLS model developed during 2015/2016 mango season was not appropriate to predict the DM content of fruit from 2016/2017 season (R² not adjusted). Therefore, the ... (Complete abstract click electronic access below) / Doutor
43

Efeito de atmosferas hiperbáricas na pós-colheita de manga palmer /

Silva, Josiane Pereira da January 2016 (has links)
Orientador: Ben-Hur Mattiuz / Coorientador: Giuseppina Pace Pereira Lima / Banca: Clément Vigneault / Banca: Kelly Magalhães Marques / Banca: Renata Aparecida de Andrade / Banca: Teresinha de Jesus Deleo Rodrigues / Resumo: O objetivo do presente trabalho foi estudar o efeito de atmosfera hiperbárica na conservação pós-colheita de manga 'Palmer'. Os experimentos foram realizados no Laboratório de Pós-colheita da FCAV-UNESP, Câmpus de Jaboticabal. Foram utilizadas mangas 'Palmer' no estádio de maturação fisiológica, procedentes de pomares da empresa Ogata Citrus, no município de Taquaritinga-SP. Na primeira etapa os tratamentos consistiram em colocar os frutos em câmaras hiperbáricas e aplicar cinco níveis de pressão (1, 2, 4, 6 e 8 atm) à 22±1 °C e de 1 atm à 12°C. A umidade relativa (interior das câmaras) foi equilibrada a 98-100%. As mangas foram armazenadas por 2, 4 e 6 dias. Ao término de cada período de armazenamento, um lote dos frutos foi avaliado imediatamente e outro lote mantido em local com condição de ambiente (22 °C, 51-53%UR, a 1 atm) por mais 3 dias. Na segunda etapa os tratamentos consistiram em submeter as mangas às condições de pressão de 1, 2, 4, 6 e 8 atm e temperatura de 12±1 ºC. A umidade relativa do interior das câmaras foi equilibrada a 98-100% e o armazenamento foi realizado por 6 e 12 dias, nos diferentes níveis de pressão. Ao término de cada período hiperbárico, um lote dos frutos foi avaliado imediatamente e outro lote mantido em local com condição de ambiente (22 °C, 83-87% UR, a 1 atm) por mais 2 e 4 dias. Foram realizadas análises quanto a perda de massa fresca, firmeza, coloração da casca e da polpa, ácido ascórbico, teores de sólidos solúveis, acidez titulável, a... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The purpose of the present work was to study the effect of hyperbaric atmospheres in the postharvest conservation of 'Palmer' mango. The experiments were carried out in the Post-Harvest Laboratory of FCAV-UNESP, Jaboticabal Campus. Palmer' mangoes were used at the stage of physiological maturation, from orchards of the Ogata Citrus Company, in the city of Taquaritinga-SP. In the first stage the treatments consisted in placing the fruits in hyperbaric chambers and applying five pressure levels (1, 2, 4, 6 and 8 atm) at 22 ± 1 °C and 1 atm at 12 °C. The relative humidity (inside the chambers) was balanced at 98-100%. Mangoes were stored for 2, 4 and 6 days. At the end of each storage period, one batch of the fruits was evaluated immediately and another batch kept in a room with ambient condition (22 °C, 51-53% RH, 1 atm) for a further 3 days. In the second stage the treatments consisted in subjecting the mangoes to pressure conditions of 1, 2, 4, 6 and 8 atm and a temperature of 12 ± 1 ºC. The relative humidity inside the chambers was equilibrated to 98-100% and storage was performed for 6 and 12 days at different pressure levels. At the end of each hyperbaric period, one batch of the fruits was evaluated immediately and another batch kept in a room with ambient condition (22 °C, 83-87% RH, 1 atm) for another 2 and 4 days. Fresh mass loss, skin and pulp color, ascorbic acid, soluble solids content, titratable acidity, total antioxidant activity, phenols, total carotenoids, soluble sugars, polyamines, enzymatic activity and respiratory rate were analyzed. The pressure of 8 atm slowed the ripening of the fruits under ambient conditions and at 12 °C, with lower mass loss, lower SS content and higher AT, lower amount of β-carotene, lower sugar content and reduction of respiratory rate. / Doutor
44

The impact of value addition to fresh mangoes on the Socio-economic development of small scale mango farmers in Ghana

Jašková, Ivana January 2015 (has links)
This diploma thesis aims to analyse the possibilities of processing the mangoes that farmers in Ghana regularly discard. Furthermore, it demonstrates, that by adding a value to the mango processing industry, the income of a farmer in Ghana could be considerably increased, leading to higher standard of living. The practical part of the thesis is based on literature research and introduces a business plan for the mango jam production in the Eastern Region, using simple and technologically undemanding processes. The study also provides economic calculations and overall project assessment. The estimated socioeconomic impacts of processing the mango surplus on the farmer can be found at the end of the thesis.
45

Fenologia, produção e qualidade dos frutos de cultivares de mangueira em condições subtropicais

Souza, Jackson Mirellys Azevêdo [UNESP] 06 March 2014 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-03-06Bitstream added on 2014-06-13T19:34:19Z : No. of bitstreams: 1 000752817.pdf: 24498309 bytes, checksum: 8c224707e07a8f98b1acd3ba5114a25f (MD5) / Devido à enorme diversidade de cultivares e híbridos, assim como diferentes condições edafoclimáticas, o estudo do comportamento das cultivares de mangueira nas distintas regiões produtoras é de grande importância. Diante do exposto, objetivou-se neste trabalho avaliar a fenologia, a produção e a qualidade dos frutos de cultivares de mangueira em condições subtropicais do estado de São Paulo. O experimento foi realizado na Fazenda Experimental São Manuel da Faculdade de Ciências Agronômicas da UNESP em São Manuel-SP. Foram avaliadas as cultivares Espada Vermelha, Keitt e Palmer. O delineamento experimental adotado foi em blocos casualizados, utilizando-se uma planta por parcela e 10 repetições. A fenologia foi avaliada considerando-se o número de dias para formação da panícula e das fases de desenvolvimento dos frutos, além da curva de crescimento dos mesmos e a exigência térmica. As avaliações referentes à produção foram: número de frutos produzidos por planta e por panícula; porcentagem de abortamento, produção, produtividade, eficiência produtiva e sazonalidade de produção. Quanto à análise física dos frutos, foram avaliados os diâmetros longitudinal e transversal, o formato e a massa do fruto, o rendimento de polpa, casca e caroço, calibre e cor da casca e da polpa. Em relação às características químicas e bioquímicas, avaliou-se: acidez titulável, sólidos solúveis, “Ratio”, índice tecnológico, teor de ácido ascórbico, açucares redutor, não-redutor e total, carotenóides, atividade antioxidante, flavonóides e polifenóis. Com base nos resultados observou-se que as três cultivares avaliadas possuem duração dos estádios fenológicos distintas. A cultivar Keitt apresenta maior número de dias e maior exigência térmica para atingir a maturidade fisiológica dos frutos. As curvas de crescimento dos frutos de ‘Espada Vermelha’, Keitt’ e... / Due to the enormous diversity of cultivars and hybrids, as well as different environmental conditions, the study of the performance of mango cultivars in different regions is of great importance. Given the above, this study aimed to assess the phenology, production and fruit quality of mango cultivars in subtropical conditions of the state of São Paulo. The experiment was conducted at the Experimental Farm of San Manuel Faculty of Agricultural Sciences, UNESP in São Manuel-SP. The Espada Vermelha, Keitt and Palmer were evaluated. The experimental design was randomized blocks, with one plant per plot and 10 repetitions. Phenology was evaluated by considering the number of days and the panicle formation stage of fruit development, plus the growth of the same and the thermal demand curve. For the production was evaluated: number of fruits per plant and per panicle, percentage of abortion of fruits, production, productivity, production efficiency and seasonality of production. For the physical analysis of the fruits were evaluated: longitudinal and transverse diameters, the shape and weight of the fruit, the yield of pulp, peel and seed, size and color of the skin and pulp. Regarding the chemical and biochemical characteristics were assessed: titratable acidity, soluble solids, Ratio, technological index, ascorbic acid, reducing sugars, non-reducing sugars, total sugars, total carotenoids, antioxidant activity, flavonoids and polyphenols. Based on the results it was observed that the three cultivars have different duration of phenological stages. The cultivar Keitt had the greatest number of days and thermal requirement to reach physiological maturity of the fruit. The growth curves of the fruit of ‘Espada Vermelha’, ‘Keitt’ and ‘Palmer’ behave the same way as a function of days after anthesis, and follow sigmoidal model. The 'Palmer' is a cultivar with better performance, with the highest ...
46

Estratégias de gestão da cadeia de suprimento da manga brasileira destinada ao mercado externo. / Mango supply chain management strategy to external market.

Daniel Luís Pinheiro da Costa 15 September 2006 (has links)
O Brasil é um dos três maiores produtores mundiais de frutas tropicais, com uma produção que supera os 31 milhões de toneladas. Porém, apesar dessa potencialidade, as transações de comércio exterior de frutas frescas são deficitárias. Inicialmente esta pesquisa identificou os fatores relevantes para exportação de frutas relacionados às áreas de produção, processamento, distribuição, comercialização e consumo, a fim de se compreender melhor o gerenciamento da cadeia de suprimento da fruticultura destinada ao mercado externo. Alguns dos fatores efetivamente abordados foram as etapas operacionais da cadeia de suprimento internacional da manga brasileira (comércio exterior e logística), as peculiaridades operacionais, a garantia da segurança e da qualidade da manga, as melhores práticas dos fornecedores de frutas no mercado internacional e os fatores limitantes da exportação de manga brasileira nos principais mercados internacionais. Após identificação e análise dos fatores relevantes, focou-se a cadeia da manga especificamente e, com base nas teorias sobre estratégias e gestão de cadeia de suprimento, foi proposto um modelo para orientar a escolha de estratégias de gestão da cadeia de suprimento da manga brasileira destinada ao mercado externo. O modelo proposto leva em consideração a estratégia competitiva da empresa e a estratégia de cadeia de suprimento, a fim de obter o melhor alinhamento entre as duas, para atender coerentemente as expectativas do mercado-alvo. / Brazil is one of the largest producers of tropical fruit in the world, with a production of more than 31 million tones. However, in spite of its large capacity, Brazil runs a trade deficit in fresh fruit. First, this research identifies the factors relevant to the exportation of fruit in the areas of production, processing, distribution, commercialization and consumption with the objective of understanding better the supply chain management of fruit growing for the foreign market. Some of the factors which considered are the operational stages of the international supply chain of Brazilian mango (foreign trade and logistics), operational peculiarities, the safety and quality of the mango, the best practices of fruit suppliers of the international market and the factors limiting the export of Brazilian mango to the principal international markets. After identification and analysis of the relevant factors, the focus becomes specifically the mango chain and, based on strategy and supply chain management theory, a model is proposed to guide the choice of management strategy of the supply chain of Brazilian mango for the foreign market. The model which is proposed takes into account the competitive strategy of the firm and the supply chain strategy to obtain the best alignment of the two for serving coherently the expectations of the target-market.
47

Processamento descontínuo de purê de manga (Mangífera indica Linn.), variedade Haden: estudo da viabilidade do produto para pronto consumo. / Batch processing of mango puree, Haden variety: study of the viability of ready-to-serve product.

Aurea Yuki Sugai 27 September 2002 (has links)
No presente projeto, foi estudada a viabilidade do purê de manga (Mangifera indica Linn.), variedade 'Haden', para pronto consumo. Inicialmente foi feito o acompanhamento do processo de amadurecimento das mangas para determinar o estágio de maturação adequado para o processamento do purê. Foram feitas análises de firmeza, pH, acidez titulável expressa em porcentagem de ácido cítrico, sólidos solúveis e teor de pectina da polpa das frutas. Os resultados mostraram que a coloração da casca foi um bom indicador do estágio de maturação das mangas. Após acidificação, foram alicados no purê quatro tratamento térmicos diferentes: 25,5 minutos a 65°C; 16,0 minutos a 75°C; 4,0 minutos a 80°C e 2,5 minutos a 95°C. Purê tratado e não tratado termicamente foi mantido sob refrigeração durante 36 dias e análises de pH e acidez titulável, além da contagem de bolores e leveduras, foram realizadas no purê na freqüência de 7 dias. Apesar da análise estatística indicar diferenças significativas entre os valores de pH e acidez titulável em função do tempo de armazenamento e do tratamento térmico, o purê apresentou valores dentro dos limites estabelecidos pela legislação para purê de manga destinado ao consumo como bebida (valor de pH entre 3,3 e 4,5 e acidez titulável mínima de 0,32% de ácido cítrico). Em relação à contagem de bolores e leveduras, o purê tratado termicamente mostrou-se estável, apresentado contagem zero dos microrganismos citados durante todo o período de armazenamento. Estudo do comportamento reológico do purê tratado e não tratado termicamente indicou o seu caráter não-newtoniano, de natureza pseudoplástica. Apesar dos tratamentos térmicos apresentarem valores de F bem distintos, as análises físico-químicas, a contagem de bolores e leveduras e o estudo reológico mostraram que não houve diferença entre os produtos finais. Isso indica que a estabilidade físico-química e microbiológica do purê pode ser alcançada com o tratamento térmico que apresentou o menor valor de F, no caso, o tratamento conduzido a 65ºC durante 25,5 minutos. Em um teste de aceitação do consumidor, o purê tratado nestas condições apresentou um alto indice de aceitação, o que reforça a viabilidade do produto pronto para consumo. / In this research project, the viability of 'Haden' mango puree (Mangifera indica Linn.) as a ready-to-serve product was studied. The ripening process of the fruti was studied to determine the adequate stage for the puree production. Firmness, pH, total acidity expressed as citric acid percentage, soluble solids and pectin content of the fruti pulps were analyzed. results showed that color of skin is a good parameter to indicate the mangoes ripening stage. Four different heat treatments were applied to the acidified puree: 25.5 minutes at 65°C; 16.0 minutes at 75°C; 4.0 minutes at 80°C and 2.5 minutes at 95°C. Non treated and treated puree were maintained under refrigeration for 36 days. pH, titrable acidity, molds and yeast analyses were carried out weekly. Although statistical analyses indicate significant difference among pH and acidity values in relation to storage time and heat treatment, the puree presented acceptable values by Brazilian legislation for mango puree consumed as beverage (pH between 3,3 and 4,5 and mininum total acidity of 0,32% of citric acid). Heat treated puree showed microbiological stability, presenting zero count of these microorganisms during the storage time. The study of rheological behavior of treated and non treated purees revealed non Newtonian character of shear thinning nature. Even though the heat treatments presented very distinct F values, the physical chemical analyses, the mold and yeast counts and the rheological behavior showed that there was difference among the final products. This indicates that the stability os the puree can be achieved applying the heat treatment with the smallest F value, that is 25.5 minutes at 65°C. Consumer acceptance test of puree treated in these conditions presented high level of acceptance, which reinforces the viability of this puree as a ready-to-serve product.
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Desenvolvimento de tecnologia alternativa para concentração de polpa de manga / Development of alternative technology for concentration of mango pulp

Oliveira, Silvana Belem 04 January 2011 (has links)
Orientador: Roberto Hermínio Moretti / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-17T20:38:53Z (GMT). No. of bitstreams: 1 Oliveira_SilvanaBelem_M.pdf: 957114 bytes, checksum: e00ba608f56d8c72b48fb72550e50759 (MD5) Previous issue date: 2011 / Resumo: O presente trabalho teve como objetivo o desenvolvimento de uma tecnologia mais simples para concentração de produtos viscosos e obtenção de polpa concentrada de manga com maior retenção das características sensoriais e nutricionais e boa aceitação do produto por parte dos consumidores. A polpa integral de manga sofreu tratamento enzimático e centrifugação variando-se o número de gravidades e o tempo na centrífuga. Foram separadas duas frações, a polpa precipitada e o suco clarificado de manga. A melhor condição para separação das frações da polpa de manga integral escolhida foi tempo de centrifugação de 15 minutos, número de gravidades 5000G e concentração de pectinase de 16ppm, para obtenção de um rendimento ao redor de 75% de suco clarificado. O suco clarificado foi concentrado por 2,5h quando atingiu 60°Brix. Após isto, o mesmo foi reconstituído com proporções diferentes de polpa precipitada (1= 30%, 2= 67% e 3= 0% de polpa precipitada adicionada), sendo a formulação que obedeceu às frações originais das partes separadas (67% de polpa precipitada) obteve menor brix (29,8°Brix) e diferença total de cor e melhores resultados para teor de carotenóides e fibras. Foram elaborados néctares a partir dos concentrados obtidos e submetidos a análise sensorial. A formulação B (maior teor de polpa precipitada) apresentou os melhores resultados para todos os atributos / Abstract: This study aimed to develop a simpler technology for concentration of viscous products and obtaining concentrated mango pulp with better retention of nutritional and sensory characteristics and good product acceptance by consumers. The whole pulp mango enzyme treatment and centrifugation suffered varying the number of severity and duration of the centrifuge. Two fractions were separated, the pulp and precipitated clarified juice of mango. The best condition for separation of fractions of mango pulp was chosen integral centrifugation time of 15 minutes, number and severity 5000G pectinase concentration of 16ppm, to obtain a yield around 75% of clear juice. The clarified juice was concentrated by 2.5 h when it reached 60 ° Brix. After that, it was reconstituted with different ratios of precipitated pulp (a = 30%, 67% and 2 = 3 = 0% pulp precipitated added), and the formulation that followed the original fractions of the separate parts (67% pulp precipitated) had lower Brix (29.8 ° Brix) and total color difference and better results for carotenoids and fiber. Nectars were prepared from the concentrates obtained and subjected to sensory analysis. Formulation B (higher pulp content hasty) showed the best results for all attributes / Mestrado / Engenharia de Alimentos / Mestre em Tecnologia de Alimentos
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Mango butter financial feasibility analysis: value added in the Chittoor District, Andhra Pradesh, India

Pendurthi, Sita Mahalakshmi January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Allen M. Featherstone / Mango butter is one of the byproducts from mangos that is mostly used in the cosmetic and soap industry. Hydraulic pressing is one way to extract the oil from the mango kernel. Hydraulic pressing is more cost effective for small scale processors due to both a relatively lower initial and operating cost. Moreover, the processing produces uncontaminated oil and a pure cake residue when compared to screw press or solvent extraction method. This thesis was undertaken to study the financial feasibility of value added to the mango by manufacturing mango butter in the Chittoor district, Andhra Pradesh India. The Totapuri mango variety is studied. A number of locations in India were evaluated for the manufacturing unit location considering the area of production, mango productivity and the presence of pulp factories for raw material sourcing. The analysis indicated that the Chittoor district in Andhra Pradesh, India has a cluster of mango pulp factories that are reliable sources of raw material. Indian consumers are generally quick to adopt new products with better experiences and more convenience. This study identifies additional uses for mango butter in countries that consume mango butter, and highlights products with which mango butter would be in competition. The advantages and limitations of competitors producing in the Indian market are discussed. The recommendation of this study is that entrepreneurs should study the sector thoroughly before investing in mango butter production. Project size and outlay of the depend upon the market size, the type of technology that will be used and how automated the project will be. New entrepreneurs may partner with existing merchant exporters initially to gain entry into international markets. Once entry is obtained, vast export potential for such products can be slowly tapped.
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Seasonal growth patterns and water relations in response to reduced irrigation regimes in mango (Mangifera indica L.)

De Villiers, Adriaan Jacobus 17 February 2006 (has links)
Please read the abstract in the section 00front of this document / Dissertation (MSc Agric (Horticulture))--University of Pretoria, 2006. / Plant Production and Soil Science / unrestricted

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