Selective partition of caffeine from coffee bean and guaraná seed extracts using alcohol–salt aqueous two-phase systems

ABSTRACT

This work proposes the application of flexible alcoholic aqueous two-phase systems to manipulate the partition of caffeine. An optimization study was performed the caffeine partitioning towards top phase (60.0 wt% 2-propanol + 20.0 wt% K₃PO₄ at 303 K – K_caf = 3.4 and R_T = 89.1%) and bottom phase (60.0 wt% methanol + 17.5 wt% K₂HPO₄/KH₂PO₄ at 278 K – K_caf = 0.06 and R_B = 81.1%). These processes were evaluated by applying them to real biomass as guaraná seeds (purification factor (PF) = 6.59-fold) and coffee beans (PF = 3.24-fold) for the 2-propanol and K₂HPO₄/KH₂PO₄ system.

KEYWORDS:

• Alcohol
• aqueous two-phase systems
• caffeine partition
• potassium phosphate salts

Funding

The authors are grateful for the financial support from FAPITEC, for the scholarship of I.A.O. Reis and S.B. Santos, and CAPES for the scholarship of S.B. Santos. This work was developed within the scope of the project CICECO-Aveiro Institute of Materials (Ref. FCT UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when applicable co-financed by FEDER under the PT2020 Partnership Agreement. The authors also thank Fundação para a Ciência e a Tecnologia (FCT) for the postdoctoral grant SFRH/BPD/79263/2011 of S.P.M. Ventura.

Additional information

Funding

The authors are grateful for the financial support from FAPITEC, for the scholarship of I.A.O. Reis and S.B. Santos, and CAPES for the scholarship of S.B. Santos. This work was developed within the scope of the project CICECO-Aveiro Institute of Materials (Ref. FCT UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when applicable co-financed by FEDER under the PT2020 Partnership Agreement. The authors also thank Fundação para a Ciência e a Tecnologia (FCT) for the postdoctoral grant SFRH/BPD/79263/2011 of S.P.M. Ventura.