Pores and physico-chemical characteristics of dried tuna produced by different methods of drying

Rahman, M. Shafiur; Al-Amri, Omar Saud; Al-Bulushi, Ismail M.

doi:10.1016/s0260-8774(01)00169-8

Cited by 90 publications

(70 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The fat oxidation (peroxide value) in sardines dried using raised open rack dryers was also lower than for those dried using the convectional traditional drying method (Table 2). This was similar to the observations reported by Rahman et al (2002) in peroxide value variations in tuna dried using air, vacuum and freeze drying methods.…”

Section: Discussionsupporting

confidence: 92%

Biochemical and Nutritional Quality of Dried Sardines using Raised Open Solar Rack Dryers off Kenyan Coast

Ochieng¹,

Oduor²,

Nyale³

2015

J. of Food Resource Science

View full text Add to dashboard Cite

Normally sardines are traditionally sun dried unhygienically by spreading on sandy seashores, mats or tarpaulins along the Kenyan coast. However, these convectional traditional solar methods of drying fishes intended for human consumption have serious health hazards due to employment of improper and unscientific methods. Quality assurance of processed seafood is therefore of utmost concern that has greater public health implications. Therefore, in order to overcome the traditional sun drying drawbacks, an investigation was carried out to assess the biochemical and nutritional quality changes in dried sardines using a raised open rack system. The system performance was evaluated in terms of sardine drying rates, biochemical and nutritional quality attributes. Quality attributes were assessed by determining proximate composition, yeast, mold and bacterial counts, peroxide value and color L, a, b values. The results indicated a significant variation in drying rates and assessed quality attributes compared to the convectional traditional sun drying method.

show abstract

Section: Discussionsupporting

confidence: 92%

Biochemical and Nutritional Quality of Dried Sardines using Raised Open Solar Rack Dryers off Kenyan Coast

Ochieng¹,

Oduor²,

Nyale³

2015

J. of Food Resource Science

View full text Add to dashboard Cite

show abstract

“…Poderá existir espaço vazio interparticulares de várias dimensões, que serão progressivamente preenchidos com o aumento da pressão. Estes resultados foram semelhantes aos encontrados para atum desidratado 24 …”

Section: Porosidade Das Microcápsulasunclassified

“…10 Além disso, de acordo com Rahman, Al-Amri e Al-Bulushi, 24 esta função é muito importante na caracterização de poros, já que esta é utilizada nas análises de distribuição de tamanho de poros Dv(d), Ds(d) e fração de número de poros.…”

Section: Figura 4 Perfil Obtido Para Função Dv/dp Versus Diâmetro Dounclassified

Avaliação da porosidade de microcápsulas contendo proteína bioativa por porosimetria de mercúrio e adsorção de nitrogênio

Porte¹,

Leão²,

Porte³

2011

Quím. Nova

View full text Add to dashboard Cite

Recebido em 2/3/11; aceito em 27/4/11; publicado na web em 14/6/11 EVALUATION OF POROSITY OF MICROCAPSULES CONTAINING BIOCATIVE PROTEIN BY MERCURY POROSIMETRY AND NITROGEN ADSORPTION. Microcapsules containing lactoferrin were produced by spray drying using dextrin:octenylsuccinate starch, as wall materials. Porosity characteristics of spray-dried microcapsules were investigated by mercury intrusion porosimetry and nitrogen adsorption. The outer and inner structures of microcapsules were studied by Scanning Electron Microscopy and sizes were determined by Laser Diffraction. Results indicate that all microcapsules presents adsorption isotherm of type II and that micropores on the microcapsules surface will be very few or none. Our results show that microstructure, surface area and size of microcapsules are affected by dextrin: octenylsuccinate starch proportion. Pore characteristics for various microcapsules are found to be different.Keywords: porosity; microcapsules; spray drying. INTRODUÇÃOTem surgido um crescente interesse em relação às atividades fisiológicas e biológicas de algumas frações proteicas presentes no soro de leite como, por exemplo, a proteção da flora intestinal contra bactérias enteropatogênicas, proteção do organismo contra íons metálicos livres, transporte fisiológico de ferro e imunorregulação, desempenhadas ou propiciadas pela lactoferrina. Considerando as propriedades únicas que esta proteína pode conferir a determinados alimentos e a demanda atual por sistemas antimicrobianos e funcionais naturais, percebe-se a aplicação potencial da lactoferrina encapsulada na indústria de alimentos, permitindo futuramente a abertura de um novo mercado para a utilização desta proteína em alimentos industrializados.A técnica de spray drying é potencialmente adequada para encapsulação de peptídeos e proteínas por ser uma operação contínua relativamente simples e de menor custo. Contudo, durante o processo de secagem podem ocorrer diferentes graus de colapso, que determinarão a estrutura do produto final. 1A encapsulação é o processo pelo qual um material ou mistura de materiais chamados de núcleo ou material ativo são revestidos com ou contidos dentro de um outro material ou sistema, chamado de material de parede ou encapsulante. 2Para microencapsulação por spray drying, a escolha do material de parede é crítica, pois irá influenciar a estabilidade da dispersão antes da secagem e as propriedades das microcápsulas após a secagem. Os materiais encapsulantes usados consistem de uma grande variedade de polímeros formadores de filme como gomas, carboidratos, celuloses, lipídeos, proteínas e materiais inorgânicos, sendo a escolha destes dependente, dentre outros fatores, das características do núcleo. 3O amido modificado octenilsuccinato possui atividade superficial, sendo capaz de reduzir a tensão superficial de uma solução, podendo ser utilizado como um emulsificante. 4,5 Durante a produção das microcápsulas, devido à alta temperatura de secagem podem ocorrer alterações na estrutura secundária da proteína utili...

show abstract

“…At this time, the sublimation front recedes from the outer surface of the foam towards the center of the sample resulting in an increased diffusion path for the sublimed moisture that was originated at the sublimation (ice) front; this renders an increased resistance to the internal diffusion of water vapor inside the sample (40,41). The shape of the curves in Fig 2a and the drying rate in Fig 2b indicate that the internal diffusion of water vapor inside the sample is controlling the freeze-drying process.…”

Section: Discussionmentioning

confidence: 99%

Physical characterization of freeze-dried foam prepared from aloe vera gel and guar gum

Santacruz-Vázquez

Cortés

2015

Vitae

View full text Add to dashboard Cite

Background: Foams are colloidal dispersions of a gas suspended in a dispersing phase, which consisting of a semi-freeze-dried or viscous liquid phase. The physical properties of food foams are the result of the bubble characteristics and their spatial arrangement. Objectives: The aim of this work was to obtain foams of A. vera gel and guar gum and describe the changes in their physical properties and microstructure during freeze-drying using the fractal dimension concept and image analysis techniques. Methods: The porosity, density, and volume expansion factor of the fresh foams that were based on the A. vera foams were determined. The kinetics of foam texture, color, porosity and microstructure of the freeze-dried foams were obtained. The fractal texture dimension of surface (FD SDBC ) and microstructure (FD ESEM ) of the foams were determined as indicators of structural changes after freeze-drying. The guar gum concentrations used to obtain the A. vera prefoam were expressed in w/w as F1 (control sample without gum), F2 (2%), F3 (4%) and F4 (6%). Results: We obtained stable freeze-dried foams of Aloe vera gel and guar gum. The porosity, density and volume expansion factor of the fresh and freeze-dried foams were affected by the addition of the guar gum. Changes in the topology of the freeze-dried foam surface during the drying process resulted in a high rugosity compared with the original smooth surface. The microstructure of the dried foam samples suggested a relationship between the gum concentration of the prefoam A. vera gel mixture and the physical properties before and after freeze-drying, such as an increase in the microstructural alterations and surface roughness during freeze-drying. The roughness of the freeze-dried foam surface, described by the FD SDBC represented the macroscopic physical changes of the samples and correlated with the changes in the foam microstructure, which were described by the fractal dimension of the Environmental Scanning Electron Microscopy ESEM microphotographs (FD ESEM ). Conclusions: The digital analysis of the structure and porosity of the freeze-dried foam can be used to quantify the effect of gum concentrations on the morphological features and physical properties of foams during freeze-drying.

show abstract

Pores and physico-chemical characteristics of dried tuna produced by different methods of drying

Cited by 90 publications

References 26 publications

Biochemical and Nutritional Quality of Dried Sardines using Raised Open Solar Rack Dryers off Kenyan Coast

Biochemical and Nutritional Quality of Dried Sardines using Raised Open Solar Rack Dryers off Kenyan Coast

Avaliação da porosidade de microcápsulas contendo proteína bioativa por porosimetria de mercúrio e adsorção de nitrogênio

Physical characterization of freeze-dried foam prepared from aloe vera gel and guar gum

Contact Info

Product

Resources

About