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Phase transitions of frozen camu-camu (Myrciaria dubia (HBK) McVaugh) pulp: Effect of cryostabilizer addition

SILVA, Mariana Altenhofen da; SOBRAL, Paulo J. do Amaral; KIECKBUSCH, Theo Guenter
Fonte: SPRINGER Publicador: SPRINGER
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
397.18797%
Camu-camu is a tropical fruit with very high vitamin C content and commercialized as frozen pulp. Enthalpies of freezing, temperatures of the onset of ice melting, and glass transition temperatures of the maximally freeze-concentrated phase (T`(g)) of camu-camu pulp and of samples containing maltodextrin (DE20) and sucrose were measured by differential scanning calorimetry. Maltodextrin exhibited the largest freeze stabilization potential, increasing T`(g) from -58.2 degrees C (natural pulp) to -39.6 degrees C when 30% (w/w) maltodextrin DE 20 was added. Sucrose showed negligible effect on T`(g) but enhanced considerably the freezing point depression and less amount of ice was formed.

Qualidade de polpa de camu-camu [Myrciaria dúbia (H.B.K.) McVaugh], submetida aos processos de congelamento, pasteurização, alta pressão hidrostática e liofilização e armazenada por quatro meses; Quality of camu-camu [Myrciaria dubia (H.B.K.) McVaugh] pulp submitted to the processes of freezing, pasteurization, high hydrostatic pressure and lyophilization and stored for four month

Moraes-de-Souza, Rodrigo Aparecido
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 22/06/2011 PT
Relevância na Pesquisa
392.98582%
Este trabalho consta de uma avaliação da qualidade intrínseca e da qualidade percebida por potenciais consumidores espanhóis de polpa de camu-camu [Myrciaria dubia (H.B.K.) McVaugh] submetida a quatro diferentes tratamentos: congelamento, pasteurização, pressurização (alta pressão hidrostática) e liofilização, armazenada congelada por quatro meses. A avaliação da qualidade intrínseca foi realizada por meio de análises dos parâmetros pH, sólidos solúveis, acidez, coloração, teores de ácido ascórbico, de compostos fenólicos e de antocianinas, e a avaliação da qualidade percebida por meio de testes sensoriais para os parâmetros aparência, cor, aroma e sabor. Este estudo justifica-se pelo reduzido consumo de camu-camu, uma fruta nativa da Amazônia com o mais elevado teor de vitamina C observado em estudos científicos (entre 1.721 e 2.900 mg de ácido ascórbico.100 g-1), e que contém outros importantes compostos com atividade antioxidante como compostos fenólicos e carotenoides. Uma das razões do baixo consumo da fruta fresca é sua elevada acidez (entre 2,31 e 3,08 g de ácido cítrico.100 g-1), portanto, é importante a apresentação de alternativas de consumo que preservem sua principal característica nutricional (elevado teor de vitamina C) e demais atividades biológicas...

Degradação da antocianina e qualidade sensorial de polpa de Juçara (Euterpe edulis) embalada e submetida à pasteurização ; Degradation of anthocyanin and sensory quality Juçara pulp (Euterpe edulis) packaged and subjected to pasteurization

Silva, Guilherme Mei
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 25/10/2012 PT
Relevância na Pesquisa
395.29254%
Os objetivos deste trabalho foram obter um processo de pasteurização da polpa de juçara embalada em bolsas plásticas (100 mL) de alta, a fim de minimizar a degradação das antocianinas, mantendo as propriedades nutricionais e organolépticas do produto, com viabilidade técnica e econômica para as comunidades tradicionais e agricultores familiares. Para tanto se avaliou a degradação da antocianina e a atividade enzimática presente na polpa de juçara, submetida à acidificação e pasteurização depois de embalada; armazenada por 60 dias; e monitorou-se a qualidade da polpa mediante análises físicas, químicas e sensoriais. A polpa foi acidificada com ácido cítrico a pH 4,0. A outra parte não sofreu processo de acidificação. Em seguida, a polpa foi embalada em sacos de polipropileno diferenciado. Por fim, as polpas, acidificadas com ácido cítrico a pH abaixo de 4,0 e não acidificada, foram submetidas aos seguintes tratamentos: armazenada sob refrigeração a 6 °C; armazenada sob congelamento a -17 °C; pasteurizada a 80 °C por 5 minutos e armazenada sob refrigeração a 6 °C; pasteurizada a 80 °C por 5 minutos e armazenada sob congelamento a -17 °C; Num segundo momento, após a realização das análises do primeiro processo...

Effect of maltodextrin on the freezing point and thermal conductivity of uvaia pulp (Eugenia piriformis Cambess)

Villa-Vélez, Harvey Alexander; Telis-Romero, Javier; Higuita, Diana Maria Cano; Telis, Vânia Regina Nicolletti
Fonte: Editora da Universidade Federal de Lavras (UFLA) Publicador: Editora da Universidade Federal de Lavras (UFLA)
Tipo: Artigo de Revista Científica Formato: 78-85
ENG
Relevância na Pesquisa
399.2173%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 09/13033-9; O ponto de início de congelamento (FPD) da polpa de uvaia com e sem aditivos - 10, 16, 22 e 28% de maltodextrina (MD), foi medido por um aparelho simples, que consiste de duas seções principais: um vaso de congelamento e um sistema de aquisição de dados. A condutividade térmica foi calculada em função da fração de água congelada e da temperatura, usando um aparelho cilíndrico coaxial duplo. Foram empregadas equações polinomiais para descrever o comportamento do ponto inicial de congelamento e da condutividade térmica. Abaixo do ponto de congelamento, a condutividade térmica foi fortemente afetada pela fração de água congelada e pela temperatura. Equações simples em termos da fração de água congelada e da temperatura podem ser ajustadas aos dados experimentais no cálculo do início do ponto de congelamento e da condutividade térmica.; The freezing point depression (FPD) of uvaia pulp with and without additives - 10, 16, 22 and 28% of maltodextrin (MD), was measured using a simple apparatus consisting of two major sections: a freezing vessel and a data acquisition system. The thermal conductivity of the pulps was also investigated as a function of the frozen water fraction and temperature using a coaxial dual-cylinder apparatus. Above the initial freezing point...

Estudo da estabilizaçãp da polpa de camu-camu (Myrciaria Dubia (H.B.K.) Mc Vaugh) congelada visando a manutenção de acido ascorbico e de antocianinas; Study of the stabilization of frozen camu-camu pulp (Myrciaria Dubia (H.B.K.) Mc Vaugh) in relation the maintance of ascorbic acid and anthocyanins

Rosalinda Arevalo Pinedo
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 12/07/2007 PT
Relevância na Pesquisa
510.38477%
O camu-camu (Myrciaria dubia H.B.K.) é uma fruta nativa da região Amazônica que apresenta um elevado teor de ácido ascórbico e de antocianinas. O presente estudo investigou o processo de conservação por congelamento da polpa de camu-camu cultivada no Estado de São Paulo visando a manutenção de fatores de qualidade. Frutos do camu-camu foram submetidos a uma inativação enzimática por imersão em água em ebulição por 60, 90, 120 e 180 segundos seguida de esfriamento em água gelada. O tempo limite para manter a integridade do pericarpo foi 120 segundos e nestas condições houve um enriquecimento da polpa com ácido ascórbico extraído da casca, no despolpamento. Polpas tratadas por 30, 60 e 120 segundos e polpa não-inativada foram armazenadas por 180 dias a temperaturas de 5oC, -10oC e ?20oC. O tratamento por 120 segundos manteve os mais altos níveis de ácido ascórbico em todas as situações. O armazenamento a ?20oC manteve por pelo menos 135 dias o conteúdo inicial de ácido ascórbico, independentemente da intensidade da inativação térmica. Polpas inativadas por 120 segundos receberam crio-protetores (15% de goma arábica, 20% de maltodextrina DE 10 e 25% de sacarose) e juntamente com polpa sem aditivos foram submetidas às mesmas condições de armazenamento descritas anteriormente. O comportamento da conservação de ácido ascórbico foi semelhante as das polpas não-aditivadas. A degradação de antocianinas é alta e ocorre nos primeiros 50 dias de armazenamento. Na estocagem a ?20oC a retenção foi em torno de 40% de sua concentração inicial...

Capacidade de desativação de espécies reativas de oxigênio por polpas de frutas congeladas; Scavenger capacity of reactive oxygen species by frozen fruit pulps

Lizziane Cynara Vissoto
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 18/10/2012 PT
Relevância na Pesquisa
419.2789%
A diversidade de frutas frescas e/ou processadas comercializadas atualmente tem conquistado cada vez mais o mercado consumidor, com destaque para a produção de polpas de frutas congeladas, que além de permitirem o consumo de frutas durante o período não sazonal, possuem diversos compostos bioativos em sua composição. A atenção que as frutas e suas polpas vêm recebendo é devido ao crescente reconhecimento da associação direta entre o consumo de frutas e de vegetais e à prevenção de várias doenças crônico-degenerativas, as quais podem ser provocadas por espécies reativas, incluindo as espécies reativas de oxigênio. Este benefício tem sido atribuído aos compostos com capacidade antioxidante presentes em frutas e vegetais, com destaque para os compostos fenólicos e o ácido ascórbico. Considerando as observações acima e o aumento na comercialização e consumo de polpas de frutas congeladas, os objetivos deste trabalho foram: (1) determinar os teores de compostos fenólicos totais (CFT), flavonoides totais (FT) e ácido ascórbico (AA) nos extratos aquosos de 18 polpas de frutas congeladas, (2) avaliar a capacidade de desativação de algumas espécies reativas de oxigênio (radical peroxila (ROO?), peróxido de hidrogênio (H2O2) e radical hidroxila (?OH) por esses extratos...

Phase transitions of frozen camu-camu (Myrciaria dubia (HBK) McVaugh) pulp: Effect of cryostabilizer addition

SILVA, Mariana Altenhofen da; SOBRAL, Paulo J. do Amaral; KIECKBUSCH, Theo Guenter
Fonte: SPRINGER Publicador: SPRINGER
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
397.18797%
Camu-camu is a tropical fruit with very high vitamin C content and commercialized as frozen pulp. Enthalpies of freezing, temperatures of the onset of ice melting, and glass transition temperatures of the maximally freeze-concentrated phase (T`(g)) of camu-camu pulp and of samples containing maltodextrin (DE20) and sucrose were measured by differential scanning calorimetry. Maltodextrin exhibited the largest freeze stabilization potential, increasing T`(g) from -58.2 degrees C (natural pulp) to -39.6 degrees C when 30% (w/w) maltodextrin DE 20 was added. Sucrose showed negligible effect on T`(g) but enhanced considerably the freezing point depression and less amount of ice was formed.

Correlation, by multivariate statistical analysis, between the scavenging capacity against reactive oxygen species and the bioactive compounds from frozen fruit pulps

Vissotto,Lizziane Cynara; Rodrigues,Eliseu; Chisté,Renan Campos; Benassi,Marta de Toledo; Mercadante,Adriana Zerlotti
Fonte: Sociedade Brasileira de Ciência e Tecnologia de Alimentos Publicador: Sociedade Brasileira de Ciência e Tecnologia de Alimentos
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2013 EN
Relevância na Pesquisa
401.79812%
The contents of total phenolic compounds (TPC), total flavonoids (TF), and ascorbic acid (AA) of 18 frozen fruit pulps and their scavenging capacities against peroxyl radical (ROO•), hydrogen peroxide (H2O2), and hydroxyl radical (•OH) were determined. Principal Component Analysis (PCA) showed that TPC (total phenolic compounds) and AA (ascorbic acid) presented positive correlation with the scavenging capacity against ROO•, and TF (total flavonoids) showed positive correlation with the scavenging capacity against •OH and ROO• However, the scavenging capacity against H2O2 presented low correlation with TF (total flavonoids), TPC (total phenolic compounds), and AA (ascorbic acid). The Hierarchical Cluster Analysis (HCA) allowed the classification of the fruit pulps into three groups: one group was formed by the açai pulp with high TF, total flavonoids, content (134.02 mg CE/100 g pulp) and the highest scavenging capacity against ROO•, •OH and H2O2; the second group was formed by the acerola pulp with high TPC, total phenolic compounds, (658.40 mg GAE/100 g pulp) and AA , ascorbic acid, (506.27 mg/100 g pulp) contents; and the third group was formed by pineapple, cacao, caja, cashew-apple, coconut, cupuaçu, guava, orange, lemon...

Effect of maltodextrin on the freezing point and thermal conductivity of uvaia pulp (Eugenia piriformis Cambess)

Villa-Vélez,Harvey Alexander; Telis-Romero,Javier; Higuita,Diana Maria Cano; Telis,Vânia Regina Nicolletti
Fonte: Editora da Universidade Federal de Lavras Publicador: Editora da Universidade Federal de Lavras
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2012 EN
Relevância na Pesquisa
399.2173%
The freezing point depression (FPD) of uvaia pulp with and without additives - 10, 16, 22 and 28% of maltodextrin (MD), was measured using a simple apparatus consisting of two major sections: a freezing vessel and a data acquisition system. The thermal conductivity of the pulps was also investigated as a function of the frozen water fraction and temperature using a coaxial dual-cylinder apparatus. Above the initial freezing point, thermal conductivity fitted the polynomial equations well. Below the freezing point, thermal conductivity was strongly affected by both the frozen water fraction and the temperature. Simple equations in terms of the frozen water fraction and temperature could be fitted to the experimental data for freezing point depression and thermal conductivity.

Identification of yeasts Isolated from processed and frozen cocoa (Theobroma cacao) pulp for wine production

Trindade,Rita de Cássia; Resende,Maria Aparecida de; Barreto,Eriana Gomes Serpa; Mendes,Taniella de Carvalho; Rosa,Carlos Augusto
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/1999 EN
Relevância na Pesquisa
390.38008%
The alternative use of cocoa (Theobroma cacao) for wine production was tested. The pulp samples, obtained from Formosa farm, Itacaré, Brazil, were diluted, homogenized and inoculated on Sabouraud dextrose agar medium (SDA) and incubated at 28º C for 5-8 days. Selected colonies were tested for the ability to ferment cocoa pulp and divided into fermentative, non-fermentative and weak/late fermentative species. Isolates characterized as fermentative were further tested in a small-scale wine production plant and identified. Species from the genus Brettanomyces constituted the main fermentative yeasts, with the exception of two Kloeckera apis samples. The final wine product was normally pale or clear, making clarification unnecessary, and with a sweet or dry pleasant flavor. The predominance of Brettanomyces species in cocoa pulp indicated its ecological importance in this environment and pointed to an active role of Brettanomyces in the deterioration process of the processed cocoa pulp.

Sensory descriptive quantitative analysis of unpasteurized and pasteurized juçara pulp (Euterpe edulis) during long-term storage

da Silva, Paula Porrelli Moreira; Casemiro, Renata Cristina; Zillo, Rafaela Rebessi; de Camargo, Adriano Costa; Prospero, Evanilda Teresinha Perissinotto; Spoto, Marta Helena Fillet
Fonte: BlackWell Publishing Ltd Publicador: BlackWell Publishing Ltd
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
409.34266%
This study evaluated the effect of pasteurization followed by storage under different conditions on the sensory attributes of frozen juçara pulp using quantitative descriptive analysis (QDA). Pasteurization of packed frozen pulp was performed by its immersion in stainless steel tank containing water (80°C) for 5 min, followed by storage under refrigerated and frozen conditions. A trained sensory panel evaluated the samples (6°C) on day 1, 15, 30, 45, 60, 75, and 90. Sensory attributes were separated as follows: appearance (foamy, heterogeneous, purple, brown, oily, and creamy), aroma (sweet and fermented), taste (astringent, bitter, and sweet), and texture (oily and consistent), and compared to a reference material. In general, unpasteurized frozen pulp showed the highest score for foamy appearance, and pasteurized samples showed highest scores to creamy appearance. Pasteurized samples remained stable regarding brown color development while unpasteurized counterparts presented increase. Color is an important attribute related to the product identity. All attributes related to taste and texture remained constant during storage for all samples. Pasteurization followed by storage under frozen conditions has shown to be the best conservation method as samples submitted to such process received the best sensory evaluation...

Relação entre o comportamento reológico e a dinâmica do congelamento e descongelamento de polpa de morango adicionada de sacarose e pectina; Relationship between the rheologic behavior and freezing and thawing dynamics of strawberry pulp adding sucrose and pectin

Fonte: Sociedade Brasileira de Ciência e Tecnologia de Alimentos Publicador: Sociedade Brasileira de Ciência e Tecnologia de Alimentos
Tipo: Artigo de Revista Científica
PT_BR
Relevância na Pesquisa
393.2364%
The physicochemical and rheological properties of strawberry (Fragaria ananassa) pulps with the addition of sucrose (0; 2.91; 10.0; 17.09; 20% weight/weight) and pectin (0; 0.15; 0.50; 0.85; 10% weight/ weight) were characterized. The relationship in rheology, freezing and thawing dynamics and the ice crystal microstructures were established. The characterizations were performed before and after the freezing/thawing process. The samples were frozen in a water-bath at –20 °C, in a stainless steel recipient with a thermal insulation at the bottom to establish the radial heat flow in an infinite cylinder. The ice fractions were calculated using mathematical equations and the polarized concentrations were evaluated at every 60 minutes. The thawing process was assessed by the relationship between time and surface area growing with the thawing process at 19 °C. The strawberry pulp was a pseudoplastic fluid. The pulps showed a sucrose and pectin synergic effect in acid environment and this fact confirmed the variation in the viscosity, thawing rate and freezing front velocity. The thawing process of the strawberries was faster for the higher concentrated samples. The microstructure of strawberry pulps was influenced by the factors studied...

Effects of added sucrose and pectin on the rheological behavior and freezing kinetics of passion fruit pulp Studied by response surface methodology

Fonte: Sociedade Brasileira de Ciência e Tecnologia de Alimentos Publicador: Sociedade Brasileira de Ciência e Tecnologia de Alimentos
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
393.2364%
The effects of pectin and sucrose addition on the rheological parameters and freezing kinetic of pas- sion fruit pulp were studied. The effect of the air–blast freezing of passion fruit at -20 °C on the rheological parameters before and after freezing was evaluated. The rheological analyses were carried out using a viscometer at 25 °C, and the readings were converted into rheolog- ical measurements using the Mitschka method and fitted to the Ostwald–de Waele model. The freezing kinetics was analyzed using a controlled–temperature cold–stage instrument, which was coupled to a microscope integrat- ed with a video capture system. The concentrations of sucrose and pectin were established using a Composite Rotational Design. The pulps combined with the addi- tives exhibited a pseudoplastic behavior, and the values for the index flow (n) and consistency index (k) before and after freezing differed and were dependent on the additive concentrations. The rates of increase for the frozen areas were evaluated in a microfreezer and were significantly influenced by the additive concentrations. These concentrations were those that presented a lower index flow and a higher consistency index. The results are discussed in terms of the solubility and interaction of the pectin added to the fruit pulp with low pH...

Effects of airflow induction on heat transfer and energy consumption while freezing passion fruit pulp in stacked boxes

Fonte: International Energy Agency Publicador: International Energy Agency
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
399.86484%
The objectives of this work were to charac- terize the energy consumption and the heat transfer process by the determination of the convective heat transfer coefficient (h) of passion fruit pulp contained in high-density polyethylene (HDPE) boxes and frozen in two conditions: without and with airflow induction, which was achieved through the installation of obsta- cles. To determine the convective heat transfer coeffi- cients, HDPE boxes containing passion fruit pulp (contained in polyethylene bags) were interspersed with boxes containing metal tanks filled with low freezing point solutions. Three types of solutions were used: ethylene glycol, propylene glycol, and ethanol. The airflow induction under the stacks of passion fruit pulp provided higher h values than without airflow induction. The calculated average values and standard deviation were 6.340±0.87 W/m 2 °C, respectively, without air- flow induction and 8.419±1.39 W/m 2 °C with airflow induction. The average reduction of the freezing time was 25 % for the boxes located at the top and 20 % in the base of the stack. This proved that directing the airflow under the stacked product promoted more uniform and efficient heat transfer. The analysis of the electrical parameter measurements revealed an approximate de- crease of 16.7 % in energy consumption due to the reduction of the freezing time...

Effect of sucrose and pectin addition on physical, chemical, thermal and rheological properties of frozen/thawed pineapple pulps

Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
402.8978%
Pectin (0-1.0 g/100 mL) and sucrose (0-20 g/100 mL) were added to pineapple pulp to improve their rheo- logical properties, thermal properties and stability after freezing and thawing processes. The properties of the mixes were characterized before and after freezing and thawing. Samples were frozen at −20 o C, and the freeze concentration was evaluated every 60 min. The thawing rate was evaluated at 19 o C and quantified by photographic editing and image analysis software. The thawing rates and values for the freeze con- centration were leveled out at pectin concentrations above 0.5 g/100 mL pectin, which indicated that pectin functions to maintain structural homogeneity during freezing. In the thawed samples, the plastic viscosity values were leveled out from pectin concentrations (0.25-0.75 g/100 mL) as the sucrose concentration increased when compared to unfrozen samples. The differences between the rheological parameters of the unfrozen and frozen/thawed pulps, the higher yield stress values after thawing were attributed to the size of suspended particles in the pulp. Applications can specify formulations of frozen products containing pec- tin, where these properties can be handled after thawing the product.

ESTABILIDADE DE COMPOSTOS BIOATIVOS EM POLPA CONGELADA DE AMORA-PRETA (Rubus fruticosus) cv.TUPY; Stability of bioactive compunds in frozen pulp of blackberry (Rubus fruticosus) cv. Tupy

JACQUES, Andressa Carolina
Fonte: Universidade Federal de Pelotas; Agronomia; Programa de P??s-Gradua????o em Ci??ncia e Tecnologia Agroindustrial; UFPel; BR Publicador: Universidade Federal de Pelotas; Agronomia; Programa de P??s-Gradua????o em Ci??ncia e Tecnologia Agroindustrial; UFPel; BR
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
491.84184%
Brazil is considered one of the major consumer??s country of fruits, occupying the third worldwide position. The diversity of fruit for the market is growing, but their properties and activities are not fully determined. However, from the beginning of the 90s, a large fruit supply is justifying studies related to the development of new products, which in most cases concentrates the major consumption form as raw fruit or pulp. This work aimed to produce pulp from blackberry cv. Tupy, and store it under different temperature conditions (-10, -18 and -80 ??C) for 6 months, evaluating the stability of its main phytochemicals after processing and during the storage period. The results showed that the temperature of -10 ??C was not sufficient to cause significant changes in relation to total phenols, total anthocyanins, antioxidant capacity and titrable acidity (2 months). The temperature of -18 ?? C was not sufficient to cause significant changes in the pulp with respect to: total phenols and antioxidant capacity (4 months), total anthocyanins (2 months) and β-carotene (6 months). At temperature of -80 ?? C, few changes were caused in the pulp stored for 6 months, and observed only small changes in soluble solids, hydroxybenzoic acid. Total and individual carotenoids in any of the three IPF temperatures sufficient to avoid losses. In Tocopherol...

Comparison of sensory attributes of fresh and frozen wine grape berries using Berry Sensory Assessment

Olarte Mantilla, S.; Collins, C.; Iland, P.; Kidman, C.; Jordans, C.; Bastian, S.
Fonte: Australian Society of Viticulture and Oenology Publicador: Australian Society of Viticulture and Oenology
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
416.21805%
Background and Aims: We examined whether a sensory difference between fresh and frozen berries could be detected using Berry Sensory Assessment (BSA). If no sensory difference was detected, then fresh berries could be frozen and assessed later, thus reducing the problem of palate fatigue for assessors. Methods and Results: Twenty-five sensory attributes of fresh and frozen Shiraz berries were evaluated by Descriptive Analysis at three times of harvest, ‘before harvest’, ‘harvest’ and ‘after harvest’. In addition total soluble solids (TSS), pH, titratable acidity (TA) and berry mass were measured for all berry samples. Five sensory attributes were consistently different at the three times of harvest – pulp sweetness, pulp fresh fig flavour, skin colour extraction, skin bitterness and seed astringency. Frozen berries were characterised by having pulp sweetness, pulp fresh ripe fig flavour and seed astringency higher than that of fresh berries. Whereas fresh berries had skin colour extraction and bitterness higher than that of frozen samples, freezing did not affect TSS, but pH in frozen berries was higher than that in fresh berries at each harvest. Titratable acidity was lower in frozen berries at harvest and at after harvest. Freezing reduced berry mass before harvest and at each harvest compared with that of fresh berries. Conclusions: Shiraz berries that are frozen and thawed have a sensory profile different to that of fresh berries. Time of harvest affects the sensory attributes of Shiraz berries...

Frozen concentrated orange juice processed by high pressure homogeneization technology = : Processamento de suco de laranja concentrado e congelado por tecnologia de homogeneização a alta pressão; Processamento de suco de laranja concentrado e congelado por tecnologia de homogeneização a alta pressão

Thiago Soares Leite
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 27/02/2014 PT
Relevância na Pesquisa
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O Brasil é o maior produtor mundial de laranja, sendo que a maior parte desta produção é destinada a fabricação do suco concentrado congelado (Frozen concentrated Orange Juice - FCOJ). Devido ao seu grande volume de exportação e sua alta consistência (viscosidade aparente), o conhecimento de suas propriedades reológicas se torna necessária para um melhor dimensionamento de equipamentos e processos. Na homogeneização a alta pressão (HAP), uma tecnologia de processamento não térmica, o produto é pressurizado e forçado a passar por um pequeno orifício aumentando drasticamente sua velocidade, fazendo a pressão diminuir para a atmosférica, causando forte cisalhamento e cavitação. Estes fenômenos causam alteração na estrutura de células e biopolímeros, impactando no tamanho das partículas e na maneira como se interagem, alterando assim, as características reológicas do produto. O presente trabalho se baseou na utilização desta tecnologia em FCOJ visando diminuição da sua consistência, e alteração de demais comportamentos reológicos, para gerar uma economia de energia em diversas operações unitárias como bombeamento, congelamento, transporte e estocagem. Reduções mesmo que pequenas na consistência possibilitam grande economia de energia devido aos grandes volumes de suco processado no Brasil. Este trabalho teve como objetivo avaliar a influência da alta pressão de homogeneização (HAP) no comportamento reológico em estado estacionário (independente e dependente do tempo). Foram avaliados também...

ASCORBIC AND DEHYDROASCORBIC ACID CONTENT OF FROZEN ACEROLA PULP (MALPIGHIA GLABRA L.) COMMERCIALIZED IN RECIFE – PE (BRAZIL); TEOR DE ÁCIDO ASCÓRBICO E DEHIDROASCÓRBICO EM POLPAS DE ACEROLA (Malpighia glabra L.) CONGELADAS E COMERCIALIZADAS NA CIDADE DO RECIFE - PE

LOPES, VERÔNICA CAVALCANTI; Universidade Federal Rural de Pernambuco; MARTINS, MARCOS HENRIQUE BRAINER; Universidade Federal Rural de Pernambuco; CARVALHO, IRINEIDE TEIXEIRA DE; Universidade Federal Rural de Pernambuco
Fonte: UFPR Publicador: UFPR
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 28/04/2009 POR
Relevância na Pesquisa
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Seventeen samples of frozen acerola pulp (Malphighia glabra L.), processed by different producers and traded in Recife, State of Pernambuco, Brazil, were investigated for the ascorbic acid and dehydroascorbic acid content, from May to June, 1995. The method used was the “Tillmans” with endofenol. The ascorbic acid concentration varied from about 602,41 mg/100 mL to 1575,49 mg/100 mL of frozen pulp.; Analisou-se dezessete amostras de polpas congeladas de acerola (Malpighia glabra L.), processadas por distintos produtores e comercializadas na cidade do Recife, no período de maio a junho de 1995. Verificou-se o teor em ácido ascórbico e dehidroascórbico (método volumétrico de “Tillmans” com indofenol), as condições de armazenamento e embalagem além da coloração das polpas. Os resultados obtidos ficaram abaixo do valor médio de outros estudos, variando de 1575,49 mg/100 mL a 602,41 mg/100 mL de polpa congelada. As condições de embalagem e armazenamento apresentaram-se insatisfatórias, podendo comprometer a vida útil do produto a ser consumido. Recomenda-se que sejam realizados outros trabalhos visando diagnosticar os fatores que podem contribuir na degradação de ácido ascórbico.

Evaluation of two human dental pulp stem cell cryopreservation methods

Munévar,Juan C; Gutiérrez,Nicole; Jiménez,Nury T; Lafaurie,Gloria I
Fonte: Acta Odontológica Latinoamericana Publicador: Acta Odontológica Latinoamericana
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2015 EN
Relevância na Pesquisa
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Dental pulp is a promising source of mesenchymal stem cells for use in cell therapy and regenerative medicine. Methods for storing stem cells with minimum compromise of cell viability, differentiation capacity and function should be developed for clinical and research applications. The aim of this study was to evaluate whether human dental pulp stem cells (hDPSCs) isolated and cryopreserved for 1, 7 and 30 days maintain viability and expression of specific stem cell markers. Human dental pulp stem cells were isolated from 23 healthy patients aged 18 to 31 years. Dental pulp was enzymatically dissociated, and CD105+ cells were separated using the Miltenyi™ system. The hDPSCs were cryopreserved using the Kamath and Papaccio methods. Post-cryopreservation viability was measured by flow cytometry (7AAD) and by the expression of the phenotype markers CD105+/ CD73+, CD34-/CD45-. The Papaccio method showed greater cell viability for cells that had been frozen for 30 days (59.5%) than the Kamath method (56.2%), while the Kamath method provided better results for 1 day (65.5%) and 7 days (56%). Post-cryopreservation expression of the markers CD105+/CD34- was greater after 1 and 7 days with the Kamath method and CD105+/CD45- were expressed after all 3 cryopreservation times. There was greater expression of CD73+ in the hDPSCs after 1 and 7 days with the Kamath method...