Recovery of Sugars and Lipids from Spent Coffee Grounds: A New Approach

Spent coffee grounds (SCG) is an agro-industrial waste which could potentially be tapped as feedstock for biofuel production. The direct hydrolysis of non-delipidated SCG was investigated in this study. Hydrolysis of SCG was carried out with the use of sulfuric acid (3-5 %v/v) as hydrolyzing medium, over a period of 30-180 min at a solvent to solid ratio of 10 mL/g at 95 A degrees C. The optimum yield (26 and 31 g/g) and recovery (86 and 78 %) of the available reducing sugar was achieved at a local optimum employing an acid concentration of 4 % and a hydrolysis time of 120 min. Lipids were recoverable from the hydrolyzed biomass residue and bound lipids were also released through the hydrolysis process resulting in a recovery of over 100 %. This approach may potentially reduce production steps, avoiding energy intensive process for removal of water content in SCG.