Increasing the sustainability of the coffee agro-industry: spent coffee grounds as a source of new beverages

This work describes a new process for the production of beverages from spent coffee grounds (SCG), as well as the chemical and sensory profiles. The process consisted of the extraction of antioxidant phenolic compounds of SCG, followed by the fermentation of this extract supplemented with sucrose and fermented broth distillation. Thus, two fermented (10.4% and 10.0% of ethanol, by volume) and two distillated (38.1% and 40.2% of ethanol, by volume) beverages were obtained. A total of 45 and 59 volatile compounds (alcohols, esters, aldehydes, terpenes, lactones, pyrazines, norisoprenoids, volatile phenols and acids) identified and quantified by GC-MS characterized the aroma and flavor of the fermented and distilled beverages, respectively. Twenty sensory descriptors define the sensory profile of the two beverages which corroborated the pleasant smell and taste of coffee in the distillate beverage. Therefore, this work demonstrates that the fermented and distilled beverages obtained from spent coffee grounds have acceptable organoleptic qualities that make them suitable for human consumption. This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by European Regional Development Fund under the scope of Norte2020 — Programa Operacional Regional do Norte. Thanks to Appellation Orujo de Galicia (Galicia, Spain).