Simple and reliable eco-extraction of bioactive compounds from dark chocolate by Deep Eutectic Solvents. A sustainable study

The green solvents and eco-extraction methods are gaining increasing interest in chemical analysis for bioactive compounds in food matrices. Deep Eutectic Solvents (DES) developed as a greener and more sustainable alternative to organic solvents, owing to their non-toxic, highly stable, and biodegradation-friendly nature. DES application for polyphenols and antioxidant compounds extraction in dark chocolate samples has been evaluated in an integrated study for sustainability assessment, based on multivariate analysis and Life Cycle Assessment (LCA) methodology. A green extraction method based on DES was proposed testing different HBA:HBD pairs (ChCl:Fru, ChCl:Teg, Bet:Fru, and Bet:Teg). DES Bet:Fru resulted in the highest extraction yield in terms of both total polyphenols (0.34–3.37 g GAE/100 g) and flavonoids (1.13–8.32 g RUT/100 g), P < 0.05. Furthermore, the environmental performances of green and conventional solvents (MeOH:H2O, H2O, and MeOH) were evaluated by applying a comparative LCA (c-LCA). The c-LCA study highlighted that conventional extraction for polyphenols in dark chocolate was 60% more impactful than DES. DES pairs analysed quantitatively lowest impacted than conventional methods, considering the macro-categories Human Health (9.99 × 10–8 ÷ 1.54 × 10–7 DALYs), Ecosystem (2.29 × 10–10 ÷ 3.57 × 10–10 species.yr), and Resources (6.57 × 10–3 ÷ 8.96 × 10–3 USD2013).