Comparison of selected clean and green extraction technologies for biomolecules from apple pomace.

Apple pomace has been considered as a sustainable source for antioxidant phenolic compounds. Previous reports show extraction of total phenolic contents (TPC) by following various conventional and non-conventional techniques; however, a comparative study has not been reported. In the present work, conventional extraction was compared with several non-conventional extraction methods including ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), high-speed homogenization (HH). Moreover, efficacy of combined treatments, including high-speed homogenization coupled with MAE and ultrasound-assisted enzymatic extraction (UAEE) was evaluated for the recovery of TPC. The results revealed that UAEE results in the highest TPC (4.62 mg GAE/g), moreover, it simultaneously enabled the recovery of low methoxy pectins with the degree of methylation ranging from 14.03- 28.85%. The LC-Q-Tof analysis revealed the presence of various phenolic acids and flavonoids. The DPPH radical scavenging assay showed that the phenolic rich extracts had IC50 values ranging from 27.1 to 54.6, depending on the extraction parameters. This article is protected by copyright. All rights reserved.