Effects of drying conditions on some physical properties of soy protein films

The influence of drying conditions (air temperature and relative humidity) on mechanical properties, solubility in water, and color of two kinds of soy protein isolate film: a commercial one (CSPI) and other obtained under laboratory conditions (LSPI) were evaluated using the response surface method...

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Detalles Bibliográficos
Autores: Denavi, Gabriela Alejandra, Tapia Blacido, D. R., Añon, Maria Cristina, Sobral, P. J. A., Mauri, Adriana Noemi, Menegalli, F. C.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2009
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/160890
Acceso en línea:http://hdl.handle.net/11336/160890
Access Level:acceso abierto
Palabra clave:CASTING
DRYING CONDITIONS
EDIBLE FILMS
MECHANICAL PROPERTIES
SOLUBILITY
SOY PROTEINS
https://purl.org/becyt/ford/2.11
https://purl.org/becyt/ford/2
Descripción
Sumario:The influence of drying conditions (air temperature and relative humidity) on mechanical properties, solubility in water, and color of two kinds of soy protein isolate film: a commercial one (CSPI) and other obtained under laboratory conditions (LSPI) were evaluated using the response surface methodology (RSM). Soy protein films were prepared by casting using glycerol as plasticizer. The films were dried in a chamber with air circulation under controlled conditions of relative humidity (24%, 30%, 45%, 60%, 66%) and air temperature (34, 40, 55, 70, 76 _C). It was verified that mechanical properties of films made from LSPI and CSPI are influenced in a very different way by the drying conditions due to a diverse initial protein conformation in both materials, as was revealed by DSC and SDS–Page studies. The solubility of the LSPI film was affected by temperature and relative humidity, being lowest (_50%) for films obtained at high RH and temperatures ranging from 45 to 76 _C. For CSPI films, in contrast, solubility did not depend on the drying process and it remained relatively constant (_40%). The optimal drying conditions determined by RSM were: 70 _C and 30% RH for CSPI films and 60 _C and 60% RH for LSPI films. Dried under these conditions, CSPI films presented a higher tensile strength, lower elongation at break, lower solubility and better water and oxygen permeability than LSPI ones.