Sequential microwave superheated water extraction of mannans from spent coffee grounds.

Highlights: [•] The feasibility of sequential Microwave Assisted Extractions of SCG is shown. [•] Five sequential MAE allows the exhaustive recovery of galactomannans (GM). [•] GM is recovered in MAE3 and mannans are obtained in MAE4 and MAE5. [•] Shorten polysaccharides are obtained with increasing of the number of extractions. [•] The un-extracted insoluble material (MAE5R) is composed mainly by cellulose (84%). [ABSTRACT FROM AUTHOR]