File:2021 Fractionation of spent coffee ground with tertiary amine extraction .pdf

Spent coffee ground (SCG) was fractionated with a tertiary amine (N,N dimethylcyclohexylamine, CyNMe2) to obtain a carbohydrate fraction rich in dietary fiber, a phenolic fraction made of chlorogenic acids (CGAs), and a lipid fraction mainly consisted of palmitic and linoleic acid. The extraction time (6–24 h) and temperature (25–45 ◦C) were evaluated at a constant solvent-to-sample ratio (12:1, v/w). The carbohydrate fraction obtained with CyNMe2 showed relative high values of total dietary fiber (63 to 83%). The highest concentration of phenolic compounds was obtained after 24 h at 25 ◦C. Seven major species of chlorogenic acids were detected within the phenolic fraction, ranging from 1.83 to 7.16 mg g− 1 of dry matter. The lipid fraction obtained with CyNMe2 was overestimated by 186% (13.91 ± 2.3 g 100 g− 1) over the Soxhlet extraction (7.48 g 100 g− 1) due to an incomplete conversion of the amine into its respective salt