Comparative Evaluation of Juices from Red-Fleshed Apples after Production with Different Dejuicing Systems and Subsequent Storage

In this work, two vintages (2019 and 2020) of red-fleshed 'Weirouge' apples were processed with the innovative spiral filter press technology to investigate juice production in an oxygen-reduced atmosphere. After pressing, a more brilliant red color and appreciably higher amounts of oxidation-sensitive constituents (ascorbic acid, anthocyanins, and colorless (poly)phenols) were seen in spiral filter pressed juices compared to those produced with conventional systems (horizontal filter press and decanter). In a subsequent stability study (24 weeks storage at 4, 20, and 37 degrees C), the color and phenolic compounds were monitored and differences in the juices produced with the different pressing-systems were widely maintained during the storage period. The analyses of the anthocyanins and colorless (poly)phenols were conducted by UHPLC-DAD-ESI-QTOF-HR-MS/MS and UHPLC-DAD. The spiral filter press emerged as a promising technology for the production of juices with a more attractive color and a better retention of oxidation-sensitive constituents during processing and storage compared to conventional juices.

Automated summary

This study investigated the juice production of red-fleshed 'Weirouge' apples using the innovative spiral filter press technology in an oxygen-reduced atmosphere. The results showed that the spiral filter pressed juices had a more brilliant red color and significantly higher amounts of oxidation-sensitive constituents compared to juices produced with conventional systems. The differences in color and phenolic compounds between the juices produced with different pressing systems were maintained during storage, suggesting that the spiral filter press is a promising technology for the production of juices with better color and retention of oxidation-sensitive constituents.