title: The type and concentration of milk increase the in vitro bioaccessibility of coffee chlorogenic acids.
abstract: Coffee with different types and concentrations of milk was digested with pepsin (2 h) and pancreatin (2 h) to simulate gastropancreatic digestion. Chlorogenic acids (CGAs) were determined by high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry in ultrafiltrate (cutoff 3 kDa) to evaluate their bioaccessibility. After digestion, bioaccessible CGAs decreased from 80.2 to 53.0 and 69.5 μmol/200 mL in coffee without milk and coffee-whole milk, respectively. When whole, semiskimmed, skimmed, or diluted milk were present, the increase in bioaccessibility was dependent on fat content (r = 0.99, p < 0.001). No relationship was observed between bioaccessibility and proteins, carbohydrates, and calcium content. The addition of milk to coffee caused an immediate decrease in the bioaccessibility due to CGAs binding to proteins. After digestion, 86-94% of bound CGAs remained in the high molecular weight fraction. Casein bound 5-caffeoylquinic acid with high affinity (K(D) of 37.9 ± 2.3 μmol/L; n = 0.88 ± 0.06).
authors.affiliation: Department of Life Sciences, University of Modena and Reggio Emilia, Via Amendola 2, 42100 Reggio Emilia, Italy. davide.tagliazucchi@unimore.it
authors.forename: Davide
authors.initials: D
authors.lastname: Tagliazucchi
authors.forename: Ahmed
authors.initials: A
authors.lastname: Helal
authors.forename: Elena
authors.initials: E
authors.lastname: Verzelloni
authors.forename: Angela
authors.initials: A
authors.lastname: Conte
mesh_terms: D000818:Animals; D001682:Biological Availability; D002726:Chlorogenic Acid / Q000493:pharmacokinetics*; D002851:Chromatography, High Pressure Liquid; D003069:Coffee / Q000737:chemistry*; D005744:Gastric Acid; D006863:Hydrogen-Ion Concentration; D008892:Milk; D013050:Spectrometry, Fluorescence; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry
chemical_list: D003069:Coffee; D002726:Chlorogenic Acid