Comparison of batch and circulating processes for polyphenols extraction from pomelo peels by liquid-phase pulsed...

The study was an attempt to compare batch and circulating processes for polyphenols extraction from pomelo peels by liquid-phase pulsed discharge (LPD) in order to assess the extraction efficiency of the two processes. Response surface methodology was used to optimize batch (8-12 kV discharge voltage, 30-50 mL/g liquid to solid ratio and 2-4 min extraction time) and circulating (8-12 kV discharge voltage, 30-50 mL/g liquid to solid ratio and 20-40 mL/min flow rate) extractions. The highest polyphenols yield was 2.50 ± 0.02% at 42.2 mL/g, 12 kV and 4 min in batch extraction, while circulating extraction produced the most polyphenols (2.42 ± 0.01%) at 43.7 mL/g, 10.4 kV and 27.6 mL/min. The results showed that batch extraction achieved much greater yields than circulating extraction with lower-cost equipment. Therefore, batch extraction was a promising technology for the separation of high value-added products from pharmaceuticals and fine chemicals.