Spanish researchers extract oil from coffee grounds while preserving the rest

In Spain, a study by the Universitat Rovira i Virgili (URV) has evaluated how to extract oil from coffee grounds efficiently while preserving the rest of the plant material so that it can also be utilized in other processes.

The research, published in Biomass and Bioenergy, focuses on spent coffee grounds, which are a very abundant waste product. According to the article, global coffee bean production stands at around 10 million tonnes per year, only a small proportion of which actually ends up in the coffee after the drink is brewed. The remainder becomes solid waste in the form of coffee grounds, which contain approximately 15% lipids, that is, fats that can serve as a basis for producing biodiesel.

In addition to the amount of oil recovered, the study emphasizes the quality of the extract. The optimized process yielded an oil with a very low impurity content of 0.3%, in contrast to Soxhlet, where this figure is 3.9%. Analysis of the fat composition showed that the fatty acid profile remained stable under different test conditions and was dominated by linoleic and palmitic acids, two components that indicate this oil’s potential as a raw material for biodiesel production.