Centrifugal filtration enhances the block freeze concentration and recovery of bioactive compounds from pomegranate juice

Pomegranate juice (PJ) is rich in bioactive compounds, offering a significant antioxidant capacity and health benefits. Centrifugation-assisted block cryoconcentration (CABC) has shown promising results, but the solute yield (SY) needs improvement. This work aims to apply the filtration and centrifugation-assisted block cryoconcentration (F-CABC) technique to improve the SY and bioactive compound content of PJ. Under the optimal contitions of 1300 RCF, 13 min, and a filter area (FA) of 3.65%, a concentrate with a concentration index (CI) 3.1, and an SY of 88% was obtained, and the anthocyanin and total phenolic contents were increased by factors of 3.6 and 3.2, respectively. The antioxidant capacity increased significantly by factors of 2.2 and 2.9, compared to the initial DPPH and CUPRAC values, respectively. At 2360 RCF for 35 min and 3.65% FA, the SY reached 97%, but the CI decreased to 2.5. F-CABC produced concentrates rich in bioactive compounds and a clear ice fraction (<0.1 degrees Brix), thus outperforming other block cryoconcentration methods.