HS–SPME–GC–MS profiling and sensory analyses of juices from red-fleshed ‘Weirouge’ apples made with innovative and conventional dejuicing systems

Abstract

Volatiles, descriptive sensory profiles as well as consumer acceptance and preference of juices from red-fleshed ‘Weirouge’ apples produced in 2019 and 2020 with three different dejuicing systems were assessed. HS–SPME–GC–MS analyses revealed differences in the profiles of volatiles in juices processed in an oxygen-reduced atmosphere with an innovative spiral filter press as compared to those obtained using conventional systems, i.e., horizontal filter press and decanter. A total of 49 volatiles was tentatively assigned and permitted a clustering of the samples according to vintage and processing technology by multivariate statistics. Tentative markers to differentiate the individual samples were deduced from the multivariate models. In both years, each three 1,3-dioxanes and C₆ alcohols were revealed as discriminative markers of horizontal filter pressed juices. Descriptive sensory analysis by trained panelists revealed higher intensity scores of ‘oxidized’ and ‘apple-like’ orthonasal odors in juices produced by horizontal filter press and decanter as compared to those obtained by spiral filter press. The visual appearance of the spiral filter pressed juices was significantly higher rated compared to those obtained by conventional pressing systems as revealed by an untrained consumer panel (n = 65). In contrast, both odor and taste were lower rated, ultimately resulting in a clear-cut higher acceptance and preference of the decanter-made juices, followed by those obtained by horizontal and spiral filter press.