Glass transition changes during osmotic dehydration

The changes in Ataulfo mangoes (Mangifera índica L.) osmotically dehydrated were evaluated through Modulated Temperature Differential Scanning Calorimetry (MTDSC) in order to determine their thermodynamic behavior due to water loss (WL) and solid gain (SG) during the process. These values were relat...

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Detalles Bibliográficos
Autores: M. E. Rosas-Mendoza, J. L. Fernández-Muñoz, J.L. Arjona-Román
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2011
País:México
Institución:Instituto Politécnico Nacional
Repositorio:Repositorio Digital del IPN
OAI Identifier:oai:www.repositoriodigital.ipn.mx:123456789/10787
Acceso en línea:http://hdl.handle.net/123456789/291
http://www.repositoriodigital.ipn.mx/handle/123456789/10787
Access Level:acceso abierto
Palabra clave:Glass transition
heat capacity
diffusion coefficients
osmotic dehydration
mango
Descripción
Sumario:The changes in Ataulfo mangoes (Mangifera índica L.) osmotically dehydrated were evaluated through Modulated Temperature Differential Scanning Calorimetry (MTDSC) in order to determine their thermodynamic behavior due to water loss (WL) and solid gain (SG) during the process. These values were related with the effective diffusion coefficients for water (Dew) and solids (Des) into the fruit. The samples were analyzed under frozen conditions. The glass transition temperature (Tg) corresponding to sucrose in concentrated solution, and the value referred as Tg´ for freeze sucrose solutions were founded. Mango Tg variation was in increasing with the WL decrement, and the melting enthalpy increase with the soluble solids increment into the fruit. As moisture content decrease by dehydration, the food matrix became more viscous and the water and solids transfer are delayed; these changes were reflected in the decrease of effective diffusion coefficients, Dew and Des, while Tg in mango samples increase. All these results show the useful with the MTDSC analysis to follow the osmotic dehydration inside the product.