Physical–chemical and sensory properties of pulsed electric field and high hydrostatic pressure treated citrus juices

The consumers have increasing desire towards fresh, long shelf-life and healthy products by consisting favourable sensory properties. As an ambivalent fact appears that the product should meet all these requirements and should be consumable long time. All these demands lead to the importance of the minimal processing methods. The properties of widely common citrus juices (100% orange, – grapefruit, – and tangerine juice) were analyzed by measuring the possible changes in the physical–chemical parameters (pH, Brix°, electric conductivity, colour) respectively the aroma and acid content. The applied technology was pulsed electric field (in furthers: PEF) treatment with the parameters of 28 kV/cm with 50 pulses; respectively high hydrostatic pressure (HHP) technology with the parameter of 600 MPa pressure for 10 min treatment time. The sensory properties of the juices were analyzed with electronic-nose and -tongue to measure the possible changes of the treated juices compared to the untreated (control) samples with the help of these electronic tools, which can serve as a potential detection system for the differentiation of the treatments mentioned above.Industrial relevanceFruit juices are preserved mainly by heat treatment which can change many prosperous flavour- , acid and sensory properties. The present work shows in case of citrus juices the application of pulsed electric field treatment and high hydrostatic pressure techniques as non-thermal preservation possibilities and the use of electronic tongue and – nose as a new method for sensory testing.

Research Highlights
► Investigation into physical–chemical and sensory properties of PEF and HHP treated citrus juices.
► Observation of differences in several aroma compositions and colour properties.
► Use of electronic tongue and – nose for the first time to show the possible differentiations of the treatment types.
► The successful distinguish of the treatment types from the control samples request further studies to verify the new method.