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

  title={Sequential microwave superheated water extraction of mannans from spent coffee grounds.},
  author={Cl{\'a}udia P Passos and Ana S P Moreira and Maria do Ros{\'a}rio Domingues and Dmitry V. Evtuguin and Manuel A. Coimbra},
  journal={Carbohydrate polymers},
The feasibility of using sequential microwave superheated water extraction (MAE) for the recovery of mannans from spent coffee grounds (SCG) was studied. Due to the high contents of mannose still present in the SCG residue left after two consecutive MAE, the unextracted material was re-suspended in water and submitted to a third microwave irradiation (MAE3) at 200 °C for 3 min. With MAE3, mannose recovery achieved 48%, increasing to 56% by MAE4, and reaching a maximum of 69% with MAE5… Expand
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Microwave superheated water extraction of polysaccharides from spent coffee grounds.
The feasibility of microwave superheated water extraction of polysaccharides from SCG was studied and it was shown that all extraction conditions allowed to obtain mainly arabinogalactans and galactomannans. Expand
Extractability and structure of spent coffee ground polysaccharides by roasting pre-treatments.
The coffee residue left after the preparation of the brew (spent coffee grounds - SCG) is very rich in polysaccharides, namely galactomannans and arabinogalactans, which are polymers that can be usedExpand
Arabinosyl and glucosyl residues as structural features of acetylated galactomannans from green and roasted coffee infusions.
Methylation analysis, hydrolysis with specific glycosidases and GC-EIMS analysis of the reduced and methylated oligosaccharides allowed to conclude that beta-(1-->4)-linked glucose residues are also structural features of green and roasted coffee galactomannans (6 and 1 mol%, respectively). Expand
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The conclusion that transglycosylation and isomerization reactions occur during dry thermal processing of coffee galactomannans is made. Expand
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The microwave-assisted method was used to extract polysaccharides from solanum nigrum. The optimum experimental parameters, mechanism of the extraction and the effect of microwave-assisted extractionExpand
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