NMR analysis of roasted coffee lipids and development of a spent ground coffee application for the production of bioplastic precursors

Multinuclear and multidimensional NMR spectroscopy was applied as a robust and rapid tool for the analysis of several classes of non-polar compounds in roasted coffee beans, coffee beverage and spent coffee grounds. In addition to various fatty acids, other compounds found in roasted coffee lipids, include oxidation and hydrolysis products, terpenes, sterols, and phospholipids. Spent coffee grounds have a similar fatty acid composition with roasted coffee beans and they are rich in Cafestol and Kawheol, which appear as esters of fatty acids. Triglycerides extracted from coffee waste using a green chemistry approach, based on supercritical CO2 extraction, are promising candidates for the production of bioplastics. Bioplastic precursors were produced using an in situ solvent-free epoxidation process and the reaction monitoring was performed using NMR spectroscopy.