Solvent and rotating bed reactor extraction with one- and two-phase solvents applied to bilberries (Vaccinium myrtillus) for isolating valuable antioxidants

Bilberry press cake is the major by-product from the production of bilberry juice. To valorize the press cake, the authors describe their work to extract antioxidant antocyanidins / antocyanins from the cake. Different solvent compositions were compared as well as traditional extraction vs. extraction by use of RBR. The methods investigated were summarized by the authors as follows:

1. "Traditional extraction using different concentrations of ethanol dissolved in water, different masses of material, and different temperatures."

2. "RBR extraction using different concentrations of ethanol dissolved in water, different masses, and temperatures."

3. "RBR extraction using two-phase system, method 3 only mass and temperature were changed."

4. "RBR extraction using two-phase system method 4, only mass and temperature were changed.”

Correlation data between extracted anthocyanidins / anthocyanins vs. time, temperature, and ethanol concentration was collected and analyzed. Eventually, an RBR extraction approach was deemed superior.

Highlights:

• “RBR allowed measurement after 2 and 4 min while for TSE [traditional solvent extraction], this could not be done.”
• “The RBR was better than traditional extraction and 16 min sufficed.”