Espresso coffee residues: a valuable source of unextracted compounds.
Espresso spent coffee grounds were chemically characterized to predict their potential, as a source of bioactive compounds, by comparison with the ones from the soluble coffee industry. Sampling included a total of 50 samples from 14 trademarks, collected in several coffee shops and prepared with distinct coffee machines. A high compositional variability was verified, particularly with regard to such water-soluble components as caffeine, total chlorogenic acids (CGA), and minerals, supported by strong positive correlations with total soluble solids retained. This is a direct consequence of the reduced extraction efficiency during espresso coffee preparation, leaving a significant pool of bioactivity retained in the extracted grounds. Besides the lipid (12.5%) and nitrogen (2.3%) contents, similar to those of industrial coffee residues, the CGA content (478.9 mg/100 g), for its antioxidant capacity, and its caffeine content (452.6 mg/100 g), due to its extensive use in the food and pharmaceutical industries, justify the selective assembly of this residue for subsequent use.
REQUIMTE, Laboratório de Bromatologia e Hidrologia, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal.
Rebeca
R
Cruz
Maria M
MM
Cardoso
Luana
L
Fernandes
Marta
M
Oliveira
Eulália
E
Mendes
Paula
P
Baptista
Simone
S
Morais
Susana
S
Casal
D000975:Antioxidants / Q000032:analysis; D002110:Caffeine / Q000032:analysis; D002726:Chlorogenic Acid / Q000032:analysis; D003069:Coffee / Q000737:chemistry*; D005227:Fatty Acids / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D008055:Lipids / Q000032:analysis; D009584:Nitrogen / Q000032:analysis; D012639:Seeds / Q000737:chemistry*; D012995:Solubility
D000975:Antioxidants; D003069:Coffee; D005227:Fatty Acids; D008055:Lipids; D002726:Chlorogenic Acid; D002110:Caffeine; D009584:Nitrogen