Sustainable utilization of cold‐pressed green coffee oil and its by‐products for high‐value materials

Abstract

In this study, the cold-pressing extraction conditions of regular and defective green coffee beans were compared to obtain green coffee oil (GCO). The total phenolic content (TPC) in GCO, press-cake, and sediment was quantified. GCO was characterized by mass spectrometry and incorporated into carboxymethyl cellulose (CMC) films. Highest TPC was found for cake and sediment from defective beans (55.8 and 41.1 mg of GAE/g dry matter, respectively). Oil yield was increased (5.9%) using the finest particle size (<850 μm). Fatty acids, phenolic compounds, and carboxyatractyloside II were identified in GCO by Direct-Infusion Electrospray Ionization-Mass Spectrometry. Films added with 0.3 ml of GCO and lecithin (0.1 g/1.5 g CMC) exhibited greater strength (38.6 MPa) and flexibility (27.6%). Results are promising for both the production of CMC-GCO films, and high-value antioxidant from GCO and its by-products with a sustainable perspective using defective Arabica beans. Practical applications Green coffee oil (GCO) added to carboxymethyl cellulose films improved mechanical properties in the presence of lecithin. GCO by-products, cake, and sediment from defective beans showed higher content of phenolic compounds than regular beans. From a sustainable and economical perspective, cold-pressed GCO and its residues can be exploited in bio-based materials and high-value antioxidants.