Freeze-dried extracts of brewed coffee were dissolved in deionized water to a concentration of 2 mg/ml and then fractionated by ultrafiltration (Millipore, Billerica, MA, USA) through a membrane with a 10 KDa nominal molecular mass cut-off membrane as described (Delgado-Andrade, Rufian-Henares, & Morales, 2005). Samples were ultrafiltrated under nitrogen (pressure of 30 psi) and residues were lyophilized to calculate the HMW MRP content in coffee brew extracts.