Clarification of olive juice by α-alumina microfiltration membranes with enhanced packing density

The development of innovative designs has enabled the creation of new-generation mineral membranes with enhanced filtration packing densities, improving their competitiveness against polymeric membranes. This study evaluates the performance of two α-Al2O3 membranes with mean pore sizes of 800 and 60...

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Detalles Bibliográficos
Autores: Gutiérrez-Docio, Alba, Ruiz-Rodríguez, Alejandro, Prodanov, M.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2025
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/391035
Acceso en línea:http://hdl.handle.net/10261/391035
Access Level:acceso abierto
Palabra clave:Olive juice
Clarification
α-Al2O3 membranes
Tangential flow membrane filtration
Phenolic and secoiridoids compounds
Microfiltration
Descripción
Sumario:The development of innovative designs has enabled the creation of new-generation mineral membranes with enhanced filtration packing densities, improving their competitiveness against polymeric membranes. This study evaluates the performance of two α-Al2O3 membranes with mean pore sizes of 800 and 600 nm and a filtration packing density of 184 m2.m−3, focusing on their operational parameters and the quality of olive juice clarification. Filtration with the 800 nm membrane achieved 2.4 times higher productivity than the 600 nm membrane. However, it left 14–19 NTU of haze in the final product and was more prone to fouling. In contrast, the 600 nm membrane produced fully clarified juice (<2 NTU) and was more resistant to fouling. Clarification with both membranes didn't produce significant retentions of the majority of the 29 examined phenolic compounds. However, retentions of 7.0 to 7.5 % of total dissolved substances, likely polysaccharide colloids, and complete removal of residual oil were achieved. Both membranes were capable of catalyzing spontaneous hydrolysis reactions that produced a significant increase in the contents of tyrosol, hydroxytyrosol and verbascoside, with oleacein concentration rising by up to 893 % in the clarified juices.