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Ascophyllm nodosum Extracts Improve Shelf Life and Nutritional Quality of Spinach (Spinacia oleracea L.)Fan, Di 29 September 2010 (has links)
In order to develop an environmentally friendly seaweed extract treatment which will benefit both pre- and post-harvest qualities of vegetables, the effects of pre-harvest application of the brown algae Ascophyllum nodosum extracts on the nutritional quality and post-harvest storability of spinach (Spinacia oleracea L.) was investigated. Plants treated with A. nodosum extracts accumulated higher concentrations of iron, potassium, total soluble protein, and total phenolics as compared to untreated controls. 1H NMR and LC-MS analysis revealed a roughly 50% enhanced accumulation of the 9 flavonoids identified, which is partially confirmed by the elevated chalcone isomerase activity. A. nodosum extract treatment caused an increase in transcription of the genes related to plant growth, osmolyte accumulation, and antioxidative activities. Post-harvest analysis revealed that A. nodosum extract treatment caused an enhanced storability of spinach leaves in terms of visual quality, weight loss, and senescence. Lipid peroxidation and ascorbate content were correlated with visual quality during storage. Animal experiments using the Caenorhabditis elegans nematode model revealed that spinach extracts prolonged the life span of C. elegans, and A. nodosum extract-enhanced polyphenols exerted improved beneficial effects in C. elegans against oxidative and heat stresses. Taken together, the results suggest that A. nodosum extracts enhance both pre- and post-harvest quality of spinach through stimulation of flavonoid pathways, thus leading to accumulation of flavonoids and promotion of anti-radical capacity in spinach leaves, which may protect the plant tissue against reactive oxygen species and subsequent decay. Furthermore, the increased flavonoid content in spinach exerted beneficial effects in C. elegans against oxidative and heat stresses via different mechanisms.
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Consumers' attitudes regarding the link between frozen and fresh vegetables and health / Emdri Maria van der WaltVan der Walt, Emdri Maria January 2003 (has links)
Vegetables and fruit appear to confer protection against various diseases, but most adults in South Africa eat substantially less than the recommended amounts. Many barriers and factors that influence vegetable consumption have been identified in the literature. One major barrier is the perishability of vegetables. Frozen vegetables can be a useful way in encouraging greater intakes. Some consumers are, however, of the opinion that processing destroy nutrients to a large extent. There is, therefore, a lack of understanding of the freezing process. Research on the attitudes of consumers towards frozen vegetables in South Africa is limited.
Objective: The purpose of this study was to determine the attitudes of consumers regarding the link between frozen and fresh vegetables and health and the attributes of frozen vegetables. Subjects/Setting: One thousand nine hundred and ninety seven South African respondents, representative of the four major race groups of South Africa (whites, blacks, coloureds and Indians) were randomly chosen from metropolitan areas from the nine provinces in South Africa. Questionnaires, existing of 17 food-related sections, including subsections on vegetables and health, were designed by researchers in co-operation with business partners. MARKINOR, a market research company, was contracted to collect the data. Respondents were questioned regarding their attitudes towards the link between frozen and fresh vegetables and health. Statistical analysis performed: The quantitative data produced by the survey was analysed by using the StatisticaⓇ-programme in order to generate the relevant tabulations, descriptive statistics and statistical tests.
Results: Overall, the attitudes of consumers towards frozen vegetables were found to be negative. Practical and statistically significant attitude differences towards frozen vegetables were found between most variables. Results from this study revealed that different levels of education, age and gender do not have a big influence on consumer's attitudes towards frozen vegetables. However, practical and statistically significant differences were found between the various LSM (Living Standards Measure) groups, especially with regard to the convenience of frozen vegetables. Results also indicated that Indians, the age group 61+ and males were the most negative towards frozen vegetables. Almost 75% of all consumers indicated that they never eat frozen vegetables. Only 1% of consumers in the LSM group 2 own a fridge/freezer. An alarmingly 26% of all consumers indicated that they are not convinced that vegetables are healthy.
Application/Conclusions: Nutrition professionals should use these findings to target messages in health-promotion programmes to increase the overall consumption of vegetables. The use of frozen vegetables by consumers with frozen storage facilities should be promoted aggressively. Consumers also need practical advice on how to overcome the barriers to dietary change. Nutrition counseling efforts should also be aimed specifically at increasing frozen vegetable consumption among targeted subgroups, particularly Indians, males and the age group 61+. It is strongly recommended that suitable measuring instruments be developed for assessing the knowledge and attitude of South Africans
towards vegetable and fruit consumption and the ability of individuals to improve their health. The results of this study may prove to be very useful in this regard. / Thesis (M.Sc. (Dietetics))--North-West University, Potchefstroom Campus, 2004.
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Perforation-mediated modified atmosphere packaging (PM-MAP) and shelf-life of pomegranate fruit arils (cv. ACCO)Hussein, Zaharan 12 1900 (has links)
Thesis (MScFoodSc)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Perforation-mediated modified atmosphere packaging (PM-MAP) offers the possibility of optimising polymeric films in order to compensate for barrier limitations of conventional modified atmosphere packaging (MAP). The aim of this study was to investigate the effects of PM-MAP and storage duration on the physico-chemical quality attributes, microbial quality, phytochemicals (anthocyanins, phenolics and ascorbic acid) and antioxidant activities of arils from fresh minimally processed pomegranate (cv. Acco). The effects of number of perforations (0, 3, 6 and 9; Ø = 0.8 mm) and storage temperature (5, 10 and 15 ºC) on water vapour transmission rate (WVTR, g/m2.day) of synthetic ‘Polylid’ and biodegradable (Nature flexTM) polymeric films were investigated. The results showed that non-perforated biodegradable film had higher WVTR at all storage temperatures, and irrespective of film type, increasing the number of perforations (from P-3 to P-9) had higher impact on WVTR than increasing storage temperature (from 5 to 15 ºC).
Furthermore, this study investigated the effects of PM-MAP on the physico-chemical properties, phytochemicals components and antioxidant activities of fresh minimally processed arils. Arils (100 g) were packaged in polypropylene trays (10.6 x 15.1 cm2) and heat-sealed with a polymeric film POLYLID®. Perforations (0, 3, 6 and 9; Ø = 0.8 mm) were made on the top of the film and all samples were stored at 5 ± 1 ºC and 95 ± 2% relative humidity for 14 days. Samples were analysed at intervals of 3, 6, 9, 12 and 15 days. Microbial analysis included tests for Escherichia coli, aerobic mesophilic bacteria, yeast and moulds at days 0, 6, 10 and 14. The results showed that headspace gas composition was significantly influenced by the number of perforations, which helped balance the decrease in O2 with corresponding increase in CO2 levels, thus preventing anoxic conditions. Total soluble solids, titratable acidity and firmness of arils were slightly reduced by PM-MAP compared to clamshell trays. Colour attributes was generally maintained across all treatments and throughout the storage duration. The highest counts of aerobic mesophilic bacteria (5.5 log CFU/g), yeast and moulds (5.3 log CFU/g) were observed in P-0 and P-9 packages, respectively. Overall, P-3 and P-6 better maintained the physico-chemical properties and microbial quality of arils. Total phenolics and anthocyanin contents were higher in arils packaged in PM-MAP while ascorbic acid was slightly reduced. Antioxidant activities tested against FRAP and DPPH radical-scavenging activity increased across all types of MAP over storage duration. However, antioxidant activities were significantly higher in pomegranate arils packaged in PM-MAP due to O2-promoted biosynthesis of phenolics and anthocyanins which constitute the antioxidant properties.
Overall, the results reported in this study showed that the use of PM-MAP in cold chain could be suitable for the preservation of physico-chemical quality, phytochemical contents and antioxidant properties of arils packaged in passive PM-MAP compared to clamshell and non-perforated packages during postharvest handling and storage. Perforating MAP films showed potential in preventing the incidence of in-package moisture condensation which is a common problem during postharvest handling and storage of fresh produce packaged inside non-perforated MAP. The results also showed the importance of keeping PM-MAP packs in closed refrigerated shelves to avoid cross contamination or ingress of foodborne pathogens. / AFRIKAANSE OPSOMMING: Perforasie-bemiddelde gewysigde-verpakking (PM-MAP) maak dit moontlik om polimeer films te optimiseer en om sodoende te kompenseer vir die versperring beperkings van die konvensioneel-gewysigde atmosfeer verpakking (MAP). Die doelwit is om die effek van PM-MAP en die duur van stoor op die fisioko-chemiese gehalte kenmerke, mikrobiale gehalte, fitochemikale (antisianien, fenolies en askorbiensuur) en antioksidant aktiwiteite van granaatarils van vars, minimaal geprosesseerde granate, te ondersoek (cv. Acco). Die effek van die aantal perforasies (0, 3, 6 en 9; Ø =0.8 mm) en stoortemperatuur (5, 10 en 15 ºC) op die waterdamp transmissie koers (WVTR, g/m2.day) van sintetiese ‘Polylid’ en biodegradeerbare (Nature flexTM) polymeriese films is ondersoek. Die resultate het bewys dat nie-perforeerde biodegradeerbare film by alle stoortemperature ’n hoër WVTR het, en dat by alle tipes film, ’n verhoogde aantal perforasies (van P-3 tot P-9) ’n hoër impak op WVTR het as ’n verhoogde stoortemperatuur (van 5 tot 15 ºC).
Verder is die effek van PM-MAP op die fisiko-chemiese kenmerke, fitochemikale komponente en antioksidant aktiwiteite van vars, minimaal-geprosesseerde granaatarils bestudeer. Die granaatarils (100 g) is verpak in in polipropilien (PP) platkissies (10.6 x 15.1 cm2) en verseël met polimeer film, POLYLID®. Perforasies (0, 3, 6 en 9; Ø =0.8 mm) is aan die bo-end van die film aangebring en alle voorbeelde is vir 14 dae teen 5 ± 1 ºC en 95 ± 2 % relatiewe humiditeit. Die voorbeelde is met tussenposes van 3, 6, 9, 12 en 15 dae ontleed. Die ontleding het toetse vir Escherichia coli, aerobiese mesofiliese bakterië, suurdeeg en skimmel op tussernposes van 0, 6, 10 en 14 dae ingesluit. Die resultate bewys dat die komposisie van die gas beïnvloed word deur die aantal perforasies. Dit help om die vermindering in O2 met ’n ooreenkomstige toename in CO2 vlakke te balanseer en om dus toestande wat deur ’n gebrek aan suurstof veroorsaak is, te verhoed. Die totaal van oplosbare vaste stowwe, titreerbare suurgehalte en fermheid van die granaatarils is deur die PM-MAP verminder veral as dit vergelyk word met “clamshell trays”. Die kleur kenmerke het oor die algemeen dieselfde gebly by al die behandelings en dwarsdeur die stoortydperk. Die hoogste aantal aerobiese mesofiliese bakterië (5.5 log CFU/g), gis en skimmel (5.3 log CFU/g) is in die P-0 en P-9 verpakkings onderskeidelik opgemerk. Oor die algemeen is P-3 en P-6 beter in staat om die fisioko-chemiese kenmerke en mikrobiale gehalte van die granaatarils te behou. Die totaal van die fenoliese and antosianiin inhoud was hoër in granaatarils wat verpak is in PM-MAP maar die askorbiensuur was effens laer. Antioksdant aktiwiteite is getoets teen FRAP en DPPH aktiwiteite het by al die tipes van MAP tydens stoor vermeerder. Antioksidant aktiwiteite was egter heelwat hoër in granate wat in PM-MAP verpak is. Dit is die gevolg van die biosintese van fenolies en antosianins wat deur O2 in die hand gewerk word en wat die basis van antioksidant kenmerke vorm.
Oor die algemeen toon die resultate van hierdie studie dat die gebruik van PM-MAP in die koue ketting geskik is vir die behoud van fisieko-chemiese gehalte, fitochemiese inhoud en antioksidant kenmerke van granaatarils wat in passiewe MAP verpak is, veral as dit vergelyk word met die vrugte wat in ‘clamshell’ en nie-geperforeerde verpakking tydens hantering na die oes en tydens stoor verpak is. Die perforeer van MAP films kan die voorkoms van die kondensasie in die verpakking verminder. Hierdie kondensasie is ’n algemene probleem tydens die hantering en stoor van vars vrugte wat in MAP sonder gaatjies verpak is. Die resultate toon ook hoe belangrik dit is om die PM-MAP verpakking in toe, verkoelde rakke te hou en om sodoende kruis-kontaminasie asook kontaminasie deur kieme wat in vrugte teenwoordig is, te voorkom.
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Utilização de filmes de quitosana contendo nisina e natamicina para cobertura de kiwis e morangos minimamente processados / Application of chitosan coatings nisin and natamicyn on kiwi and strawberry minimally processedCé, Nísia January 2009 (has links)
As frutas fornecem um aporte de vitaminas, de minerais e açúcares, além de terem substâncias com propriedades funcionais. Atualmente, por parte dos consumidores há uma crescente preocupação para encontrar no mercado alimentos que tenham sido minimamente processados, sendo que produtos com essa característica podem ser obtidos através de aplicações tecnológicas como emprego do frio, de sistemas de atmosferas controladas ou modificadas, e uso de embalagens comestíveis antimicrobianas. A perspectiva de conservação de alimentos busca a aplicação de sistemas antimicrobianos naturais onde se enfatiza a ação sinérgica de vários elementos. O objetivo geral deste trabalho foi avaliar o efeito de cobertura de quitosana em combinação com nisina e natamicina, sob refrigeração, na conservação de kiwi e morango minimamente processados. Foi avaliado o emprego de diferentes combinações de quitosana, nisina e natamicina durante o armazenamento das frutas sob refrigeração. Determinou-se a variação da atividade de água, vitamina C, pH, acidez titulável, perda de peso, sólidos solúveis, além da avaliação microbiológica das frutas, na condição de armazenamento em temperatura de refrigeração a 4 ± 2oC durante os intervalos de 1 (tempo 0), 7 e 14 dias. Os filmes com a combinação dos antimicrobianos foram eficientes para evitar a deterioração microbiológica nas frutas, mas não foram capazes de afetar positivamente os resultados das análises físico-químicas. Em kiwi, os índices de sólidos solúveis, vitamina C e pH foram os únicos afetados positivamente pelos filmes. E em morango, apenas a umidade e a vitamina C foram as variáveis que apresentaram menores perdas significativas com adição das coberturas. A aplicação dos filmes de quitosana para preservação de alimentos, além da estabilidade das frutas frente à deterioração microbiana, aumenta a garantia de obtenção de kiwis e morangos sadios minimamente processados por mais tempo. / Fruits are sources of vitamins, sugars and minerals, and contain substances with functional properties. Currently, for consumers there is a growing concern in the market to find foods that are minimally processed. The products with this feature can be obtained through technological applications such as: the use of refrigerated storage, use of or modified controlled atmospheres or applying edible antimicrobial packaging. The prospect of keeping food seeking the application of natural antimicrobial systems which emphasizes the synergistic action of several elements. This work intended to coatings of chitosan in combination with nisin and natamycin, under refrigeration in the conservation of kiwi ana strawberry minimally processed. The use of different combinations of chitosan, nisin and natamycin, in combination with temperatura refrigeration were as well evaluated. Ranges of water activity, vitamin C, pH, acidity, fresh weight loss, soluble solids, than the microbiological evaluation of fruit containing biofilms on the condition of storage temperature of refrigeration at 4 ± 2ºC, during the intervals of 0, 7, and 14 days. The biofilms in antibiotic combination were effective in reduction of microbial deterioration in the fruits, but they were not able to act positively on physical and chemical variables. In kiwi, the contents of soluble solids, vitamin C and pH were the only variables positively affected by films. And in strawberry, only the moisture and vitamin C were the variables that showed reduced losses when coatings were added. Furthermore, with the application of biofilms as food preservatives, and the stability of fruit in contrast to microbial deterioration, increase the guarantee of obtaining in minimally processed and healthy strawberries and kiwi fruit.
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Desenvolvimento e aceitabilidade de compota de figo convencional e diet / Development and acceptability of conventional fig compote and dietCaetano, Priscilla Karim [UNESP] 26 February 2016 (has links)
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Previous issue date: 2016-02-26 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Os figos são comercializados in natura ou processados na forma de doces. A preocupação com a saúde, especialmente à obesidade ou diabetes, tem feito o consumidor buscar opções menos calóricas para manter o prazer de ingerir alimentos doces. A elaboração de produtos com sabor idêntico ao convencional é de grande importância para aceitação destes produtos. O objetivo deste projeto foi desenvolver protocolos de fabricação de compota de figo diet visando o aproveitamento tecnológico e agregação de valor ao fruto respondendo aos interesses da Associação Agrícola de Valinhos e Região. Foram elaboradas compotas de figo verde avaliando diferentes edulcorantes. As formulações da calda foram: calda de açúcar (TA); Sorbitol (TS); Eritritol (TE); Sorbitol e Erititol (TSE); Steviosídeo (TST); Ciclamato de Sódio, Sucralose e Sacarina Sódica (TCSuSa); Ciclamato sódico e Sacarina sódica (TSC); Acessulfame-K e Sucralose (TAcSu); Steviosídeo, Sacarina Sódica e Ciclamato de Sódio (TSSC). Os figos in natura e as compotas foram avaliados quanto teores de sólidos solúveis oBrix, pH, acidez titulável, açúcar redutor-AR e açúcar redutor total-ART, umidade, proteínas, lipídeos e cinzas. Também foram avaliados quanto a cor instrumental, textura, análises microbiológicas e avaliação sensorial através dos testes de ordenação e teste afetivo. Para a qualidade das compotas foram determinados o peso bruto, peso líquido e peso drenado, vácuo e contagem de número de figos no pote. Os valores de todos os atributos físico-químicos avaliados estão de acordo com a literatura e legislação para este tipo de produto. A coloração do figo in natura e da compota mostraram que houve alteração na cor quando os mesmos sofreram tratamento térmico, causando modificação da cor natural dos frutos. Não ocorreu contaminação microbiológica nas compotas e se apresentaram em condições sanitárias satisfatórias. Na análise sensorial, as compotas dos tratamentos TA, TCSuSa e TSSC foram os selecionados no teste de ordenação quanto a doçura e no teste de afetivo apenas as compotas TA e TCSuSa obtiveram maiores notas para todos os escores e foram acompanhadas na vida de prateleira. No período de armazenamento (180 dias), as mesmas foram consideradas comercialmente estéreis e quanto as análises físico-químicas, a qualidade e sensorialmente, as compotas apresentaram-se estáveis durante todo o período avaliado, considerando assim um produto viável para fabricação. / Figs are marketed fresh or processed into sweets. Concern for health, especially with obesity or diabetes, have made consumers look for low-calorie options to keep the pleasure of eating sweet foods. The preparation of products identical to conventional taste is of great importance for acceptance of these products. The objective of this project was to develop diet fig compote manufacturing protocols to technological use and add value to fruit responding to the interests of the Agricultural Association of Valinhos and Region. green fig jam evaluating different sweeteners were prepared. The slurry formulations were: syrup (TA); Sorbitol (TS); Erythritol (TE); Sorbitol and Erititol (TSE); Steviosídeo (TST); Sodium cyclamate, sucralose and saccharin Sodium (TCSuSa); sodium cyclamate and Saccharin (TSC); Acesulfame-K and sucralose (TAcSu); Steviosídeo, Saccharin Sodium and Sodium cyclamate (TSSC). Figs fresh and the jams were evaluated for soluble solids ° Brix, pH, titratable acidity, reducing sugar and sugar-AR full-ART reducer, moisture, protein, lipids and ash. They were also evaluated for instrumental color, texture, microbiological analysis and sensory evaluation through the ordering and affective test tests. For the quality of jams were determined the gross weight, net weight and drained weight, vacuum and number of figs count the pot. The values of all evaluated physico-chemical attributes are consistent with literature and rules for this type of product. Staining fig fresh and compote showed that there was a change in color when they have undergone heat treatment, causing modification of the natural color of the fruit. There was no microbiological contamination in jams and presented in satisfactory sanitary conditions. In sensory analysis, the jams of TA treatments TCSuSa and TSSC were selected in order to test for sweetness and affective test only TA and TCSuSa jams obtained higher scores for all scores and were accompanied in shelf life. The storage period (180 days), they were considered commercially sterile and the physico-chemical analysis, quality and sensuously, the jams were stable throughout the study period, so considering a viable product for manufacturing. / FAPESP: 2012/15206-0
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Utilização de filmes de quitosana contendo nisina e natamicina para cobertura de kiwis e morangos minimamente processados / Application of chitosan coatings nisin and natamicyn on kiwi and strawberry minimally processedCé, Nísia January 2009 (has links)
As frutas fornecem um aporte de vitaminas, de minerais e açúcares, além de terem substâncias com propriedades funcionais. Atualmente, por parte dos consumidores há uma crescente preocupação para encontrar no mercado alimentos que tenham sido minimamente processados, sendo que produtos com essa característica podem ser obtidos através de aplicações tecnológicas como emprego do frio, de sistemas de atmosferas controladas ou modificadas, e uso de embalagens comestíveis antimicrobianas. A perspectiva de conservação de alimentos busca a aplicação de sistemas antimicrobianos naturais onde se enfatiza a ação sinérgica de vários elementos. O objetivo geral deste trabalho foi avaliar o efeito de cobertura de quitosana em combinação com nisina e natamicina, sob refrigeração, na conservação de kiwi e morango minimamente processados. Foi avaliado o emprego de diferentes combinações de quitosana, nisina e natamicina durante o armazenamento das frutas sob refrigeração. Determinou-se a variação da atividade de água, vitamina C, pH, acidez titulável, perda de peso, sólidos solúveis, além da avaliação microbiológica das frutas, na condição de armazenamento em temperatura de refrigeração a 4 ± 2oC durante os intervalos de 1 (tempo 0), 7 e 14 dias. Os filmes com a combinação dos antimicrobianos foram eficientes para evitar a deterioração microbiológica nas frutas, mas não foram capazes de afetar positivamente os resultados das análises físico-químicas. Em kiwi, os índices de sólidos solúveis, vitamina C e pH foram os únicos afetados positivamente pelos filmes. E em morango, apenas a umidade e a vitamina C foram as variáveis que apresentaram menores perdas significativas com adição das coberturas. A aplicação dos filmes de quitosana para preservação de alimentos, além da estabilidade das frutas frente à deterioração microbiana, aumenta a garantia de obtenção de kiwis e morangos sadios minimamente processados por mais tempo. / Fruits are sources of vitamins, sugars and minerals, and contain substances with functional properties. Currently, for consumers there is a growing concern in the market to find foods that are minimally processed. The products with this feature can be obtained through technological applications such as: the use of refrigerated storage, use of or modified controlled atmospheres or applying edible antimicrobial packaging. The prospect of keeping food seeking the application of natural antimicrobial systems which emphasizes the synergistic action of several elements. This work intended to coatings of chitosan in combination with nisin and natamycin, under refrigeration in the conservation of kiwi ana strawberry minimally processed. The use of different combinations of chitosan, nisin and natamycin, in combination with temperatura refrigeration were as well evaluated. Ranges of water activity, vitamin C, pH, acidity, fresh weight loss, soluble solids, than the microbiological evaluation of fruit containing biofilms on the condition of storage temperature of refrigeration at 4 ± 2ºC, during the intervals of 0, 7, and 14 days. The biofilms in antibiotic combination were effective in reduction of microbial deterioration in the fruits, but they were not able to act positively on physical and chemical variables. In kiwi, the contents of soluble solids, vitamin C and pH were the only variables positively affected by films. And in strawberry, only the moisture and vitamin C were the variables that showed reduced losses when coatings were added. Furthermore, with the application of biofilms as food preservatives, and the stability of fruit in contrast to microbial deterioration, increase the guarantee of obtaining in minimally processed and healthy strawberries and kiwi fruit.
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Desenvolvimento e caracterização de linguiça frescal de Tambaqui (Colossoma macropomum)Sleder, Fernando 10 March 2015 (has links)
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Previous issue date: 2015-03-10 / Geralmente a comercialização do pescado ainda é feita com o peixe inteiro resfriado ou congelado, sem que haja nenhum processamento para agregar valor e conveniência. Produtos processados possuem atributos sensoriais diferenciados além de facilidade no preparo. O objetivo deste trabalho foi elaborar e caracterizar, através de análises físicas e químicas, microbiológicas e sensoriais, um embutido a base de tambaqui (Colossoma macropomum). Foram desenvolvidas três formulações, que distinguiam entre si com relação ao percentual de gordura: 0%, 4,5% e 9%. Para determinação da vida de prateleira, amostras dos produtos foram armazenadas sob refrigeração 4°C por 12 dias e realizaram-se análises microbiológicas nos dias 0, 3, 7 e 12. Foram realizadas análises de composição centesimal, força de cisalhamento, perda de peso por cocção e capacidade de retenção de água. O prazo de validade dos embutidos foi estimado em 7 dias de estocagem refrigerada a 4°C. Os tratamentos apresentaram altos índices de aceitação, acima de 80%, porém, o tratamento com 9% de gordura apresentou as maiores médias nos atributos avaliados. A composição centesimal dos tratamentos apresentou as seguintes variações em g/100g: umidade 72,73 a 68,82; proteína 18,85 a 18,90; lipídeos 2,90 a 8,33 e cinza 3,86 a 4,20. A força de cisalhamento oscilou de 5,92 a 8,14 N; a capacidade de retenção de água variou de 71,83 a 74,71% e a perda de peso por cocção de 24,21 a 26,59%. / In general, fish is still sold in its entirety (whole body) cooled or frozen, with no previous processes included to add value and convenience. Processed products have different sensory attributes, in addition to ease of preparation. The objective of this study was to develop and characterize, through physicochemical, microbiological and sensory traits, a sausage based on tambaqui fish (Colossoma macropomum). Three formulations, different as to the percentage of fat — 0, 4.5, and 9% — were developed. To determine shelf life, samples of the products were stored refrigerated at 4 ºC for 12 days and microbiological analyses were performed on days 0, 3, 7, and 12. Analyses of centesimal composition, shear force, cooking weight loss and water-holding capacity were carried out. The expiration date of the sausages was estimated as seven days of storage. The treatments showed high acceptance rates, above 70%; however, the treatment with 9% fat showed the highest mean values in the evaluated attributes. The centesimal composition of the treatments showed the following variations in g/100 g: moisture, 72.73 to 68.82; protein, 18.85 to 18.90; lipids, 2.90 to 8.33; and ash, 3.86 to 4.20. Shear force varied from 5.92 to 8.14 N; water-holding capacity varied from 71.83 to 74.71%; and cooking weight loss, from 24.21 to 26.59%.
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Utilização do método de índice de qualidade (MIQ) para determinação do grau de frescor de pacu (Piaractus mesopotamicus) eviscerado e estocado em geloMartins, Marcelo Aparecido 27 February 2014 (has links)
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DISS_2014_Marcelo Aparecido Martins.pdf: 1705960 bytes, checksum: 9e9b8e77ad8f482dbf1ef2c0bea9b415 (MD5)
Previous issue date: 2014-02-27 / O objetivo deste trabalho foi desenvolver o método de índice de qualidade (MIQ) para espécie dulcícola pacu (Piaractus mesopotamicus) eviscerado, armazenado em gelo (0°C ± 0,5ºC) por 22 dias e aplicá-lo no estabelecimento da sua vida de prateleira. Para avaliar o frescor durante o armazenamento, realizaram-se análises sensoriais (MIQ) e físico-químicas (pH e Bases Voláteis Totais) nos dias 1, 4, 7, 10, 13, 16, 19 e 22 em triplicata. As corelações entre os resultados obtidos pelas análises foram utilizadas para determinar o ponto de rejeição. Os resultados indicam que o prazo de validade do pacu foi estimado em 11 dias de estocagem. O MIQ foi considerado eficiente na avaliação do frescor do pacu, já que a rejeição sensorial pelo MIQ foi determinante no estabelecimento da vida de prateleira. / This study aimed to develop the quality index method (QIM) for evaluating certain attributes of pacu, a fishwater (Piaractus mesopotamicus), gutted, stored under ice (0 °C ± 0.5 °C) for 22 days and apply the method to establish its shelf life. To assess the fish freshness during storage, sensory (QIM) and physicochemical (pH and total volatile bases) tests were performed on the first, fourth, seventh, tenth, thirteenth, sixteenth, nineteenth, and twenty-second days in triplicate. The correlations among the results obtained by the analyses were used to determine the rejection point. Results indicate that the expiration date for pacu storage was estimated in 11 storage days. The QIM was considered efficient for assessing the pacu freshness, since sensory rejection by QIM was determinative for establishing the shelf life.
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Conservação e qualidade pós-colheita em duas variedades de alface submetidas ao hidroresfriamento / Conservation and postharvest quality of two varieties of lettuce submitted to hydrocoolingFrança, Christiane de Fátima Martins 16 July 2011 (has links)
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Previous issue date: 2011-07-16 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Lettuce is a leafy vegetable highly susceptible to water loss, which reduces its shelf life and increases the final cost to the consumer. The aim of this study was to evaluate the effect of hydrocooling as the technique of pre-cooling, on the postharvest conservation of two cultivars of lettuce, ‘Vitória de Santo Antão’ type loose-smooth and the ‘Lucy Brown’ type curly cabbage, stored at 5 and 22° C, coated with polyethylene perforated plastic bags in boxes of harvest. The hydrocooling was performed by immersing the heads in a mixture of ice and water at 4°C (1:3v/v). It was evaluated the shelf life, the weight loss of fresh leaves, chlorophyll content, relative water content, total soluble sugars, reducing sugars, non-reducing sugars and starch. The hydrocooling was effective in slowing down the wilting of the leaves through storage at 5 and 22° C, promoting longer shelf life in both tested cultivars. The hydrocooling combined with storage at 5° C maintained the water balance of the leaves, keeping them hydrated during storage, and providing greater marketing period for the product. There was no effect of hydrocooling in levels of total soluble sugars, reducing, non-reducing and starch in any period of storage and temperatures for the varieties studied. In the ‘Lucy Brown’ the application of hydrocooling resulted in a dilution effect on total chlorophyll content of leaves in the analysis, but no visible changes in color was detected. In the ‘Vitória de Santo Antão’ there was no effect of treatments and storage time on the total chlorophyll content of the leaves. The hydrocooling at 4° C for 10 minutes in the type lettuce curly cabbage and for 5 minutes in the type lettuce loose-smooth, followed by storage of 5° C is an effective technique to maintain the water balance of leaves and to promoter longer shelf life of lettuce. / A alface é uma hortaliça folhosa altamente suscetível à perda de água, o que reduz sua vida de prateleira e aumenta o custo final para o consumidor. O objetivo desse trabalho foi avaliar o efeito do hidroresfriamento, como técnica de pré-resfriamento, na conservação pós-colheita de duas cultivares de alface, a ‘Vitoria-de-Santo-Antão’ do tipo solta lisa e a ‘Lucy Brown’ do tipo repolhuda crespa, armazenadas a 5 e 22°C, revestidas com sacos plásticos de polietileno perfurado em caixas de colheita. O hidroresfriamento foi realizado por imersão das cabeças em uma mistura de água com gelo a 4°C (1:3 v/v). Avaliou-se a vida de prateleira, a perda de massa das folhas frescas, teor de clorofila, teor relativo de água, teores de açúcares solúveis totais, açúcares redutores, açúcares não redutores e teor de amido. O hidroresfriamento foi efetivo em retardar o murchamento das folhas a 5 e 22°C, promovendo maior vida de prateleira nas duas cultivares testadas. O hidroresfriamento aliado ao armazenamento à temperatura de 5°C manteve o balanço hídrico das folhas, deixando-as hidratadas durante o armazenamento, promovendo maior período de comercialização do produto. Não houve efeito do hidroresfriamento nos teores de açúcares solúveis totais, redutores, não redutores e amido em nenhuma das temperaturas de armazenamento para as variedades estudadas. Nas ‘Lucy Brown’ a aplicação do hidroresfriamento resultou em um efeito de diluição no teor de clorofila total das folhas no período de análise, porém alterações visíveis na cor não foram detectadas. Na ‘Vitória de Santo Antão’ não houve efeito dos tratamentos e do tempo de armazenamento sob o teor de clorofila total das folhas. O hidroresfriamento a 4°C durante 10 minutos em alfaces do tipo repolhuda crespa, e durante 5 minutos em alfaces do tipo solta lisa, seguido de armazenamento a 5°C é uma técnica eficiente em manter o balanço hídrico das folhas e em promover maior vida de prateleira das alfaces.
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Suco desidratado de caju (Anacardium occidentale L.) por atomiza??o: caracteriza??o f?sico-qu?mica, bioativa e estudo da vida de prateleira do produtoMoraes, Francisca Pereira de 25 July 2014 (has links)
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Previous issue date: 2014-07-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Despite the relatively organized cashew (Anacardium occidentale L.) productive chain and the number of cashew derivatives found in the market, it is estimated that over 90% of the cashew peduncle is wasted. A possible strategy for a better commercial exploitation of this agroindustrial commodity would be the production of spray dried cashew pulp. Thus, this paper approaches the yellow cashew pulp spray drying process and the final product evaluation. Based on that, the shelf life of the spray dried cashew pulp packed in different packaging was evaluated. Drying was conducted in two drying temperatures (140 ?C to 150 ?C) and two concentrations of Arabic gum (AG, 15% and 25%), which summed four experimental groups. The drying performance was evaluated as well as the physicochemical characteristics (moisture, water activity, total soluble solids, pH, density, solubility, particle diameter, hygroscopicity, degree of caking, color, scanning electronic microscopy and X-ray diffraction), composition (protein, ash, fat and sugars) and bioactive and functional value (total phenolic compounds, carotenoids, ascorbic acid and antioxidant activity) of the final products. Results showed spray drying efficiency higher than 65% for all experiments, mainly for the C4 group (150 ?C and 25% AG) which reached efficiency of 93.4%. It was also observed high solubility (94.7% to 97.9%) and the groups with lower hygroscopicity (5.8% and 6.5%) were those with the highest proportion of drying coadjuvant. The particle diameters ranged between 14.7 μm and 30.2 μm and increased with the proportion of AG. When comparing the product before and after spray drying, the drying impact was evident. However, despite the observed losses, dried yellow cashew showed high phenolic concentration (from 235.9 to 380.4 mg GAE eq / 100 g DM), carotenoids between 0.22 and 0.49 mg/100 g DM and remarkable ascorbic acid levels (852.4 to 1346.2 mg/100 g DM), in addition to antioxidant activity ranging from 12.9 to 16.4 μmol TE/ g DM. The shelf life study revealed decreased phenolic content over time associated to a slight water activity increase. Overall, our results unveil the technological and bioactive potential of dried yellow cashew as a functional ingredient to be used in food formulations or as a ready-to-use product. The technological approach presented here can serve as an efficient strategy for a rational use of the cashew apple, avoiding its current underutilization / Apesar da cadeia do caju (Anacardium occidentale L.) relativamente organizada e da diversidade de derivados encontrados no mercado a partir dessa fruta tropical, estima-se que mais de 90% do ped?nculo seja desperdi?ado. Uma poss?vel estrat?gia de aproveitamento comercial do ped?nculo seria utiliz?-lo para a produ??o de polpa de caju desidratada, por meio da secagem em spray. Dessa forma, o presente trabalho aborda o processo de spray drying da polpa de caju amarelo e o estudo do produto final. A partir disso, a vida de prateleira do produto obtido acondicionado em diferentes embalagens foi avaliada. A secagem foi conduzida em duas temperaturas de secagem (140 oC e 150 ?C) e duas concentra??es de goma ar?bica (GA, 15% e 25%), constituindo assim, quatro grupos experimentais. O rendimento da secagem foi avaliado, bem como as caracter?sticas f?sico-qu?micas (umidade, atividade de ?gua, s?lidos sol?veis totais, pH, densidade, solubilidade, di?metro de part?cula, higroscopicidade, grau de caking, cor, microscopia eletr?nica de varredura (MEV) e difra??o de raios X (DRX)), composi??o (prote?na, cinzas, gordura e a??cares) e valor bioativo e funcional (compostos fen?licos totais, carotenoides, ?cido asc?rbico, e atividade antioxidante) dos produtos finais. Os resultados mostram que todos os ensaios apresentaram ?timo rendimento de secagem, com valores superiores a 65% em todos os ensaios, com destaque para o grupo C4 (150 ?C e 25% GA) que alcan?ou 93,4%. Observou-se tamb?m que os p?s apresentaram alta solubilidade (94,7% a 97,9%) e os grupos com menor higroscopicidade (5,8% e 6,5%) foram aqueles com maior propor??o de coadjuvante. O di?metro das part?culas variou entre 14,7 μm e 30,2 μm, aumentando com a propor??o de GA. Ao se comparar o produto antes e ap?s a secagem por spray, ficou claro o impacto da secagem. No entanto, apesar das perdas observadas, os p?s de caju apresentaram elevada concentra??o fen?lica (235,9 a 380,4 mg GAE eq/100 g MS), carotenoides entre 0,22 e 0,49 mg/100 g MS e consider?vel teor de ?cido asc?rbico (852,4 a 1346,2 mg/100 g MS), al?m de apreci?vel atividade antioxidante 12,9 a 16,4 μmol Trolox Eq/g MS. O estudo de vida de prateleira revelou decr?scimo do conte?do de fen?licos das amostras, al?m de ligeiro ganho de atividade de ?gua. Os resultados avaliados em conjunto mostram o potencial tecnol?gico e bioativo dos p?s de caju amarelo como ingrediente funcional a ser utilizado em formula??es aliment?cias ou como produto pronto para reconstitui??o. A rota tecnol?gica aqui apresentada pode servir como eficiente estrat?gia para melhor utiliza??o do ped?nculo de caju, evitando o alto desperd?cio desse material que se observa atualmente
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