Headspace fingerprinting as an untargeted approach to compare novel and traditional processing technologies: A case-study on orange juice pasteurisation

Effect of UV-C irradiation and heat treatment on the shelf life stability of a lemon–melon juice blend: multivariate statistical approach

“…Therefore, it is speculated that none of the treatments was able to inactivate PME completely. In fact, Vervoort et al (2012) reported that mild heat pasteurization (72°C, 20 s) of orange juice resulted in a PME activity decrease of 85%, which supports the previous statement. The absorption coefficient of the UV-C-treated sample (11.12 cm −1 ) was lower than that of the control (14.88 cm −1…”

Moderate and high intensity pulsed electric fields : Effect on microbial inactivation, shelf life and quality of fruit juices

“…In chapter 6, pulse effects responsible for microbial inactivation were distinguished from thermal effects, and two process windows were identified were pulse effects have an additional effect to the thermal effect responsible for microbial inactivation: 1) E = 15 -20 kV/cm and τ = 2 µs, and 2) E = 2.7 kV/cm and τ = 1000 µs. The effect of the first pulse condition on quality aspects is known and described in previous work Vervoort et al, 2011, Vervoort et al, 2012. These studies using electric field strength > 20 kV/cm and short pulses showed a good retention of colour, vitamin C content and flavour when compared to untreated juice, however no complete inactivation of PME was observed.…”

“…The flavour compounds in the orange juice headspace were analysed by a combination of Solid Phase Micro Extraction (SPME) and gas chromatography mass spectrometry (GC-MS), mainly according to the method described by Vervoort et al (2012). Prior to the experiments, pre-tests were carried out to select an internal standard, that did not interact with orange juice, showed no overlap with other peaks in the chromatogram, was soluble in water and stayed stable over time in the -80 °C freezer.…”

“…In a first step, each vial was equilibrated in the incubator at 40 °C for 20 min under agitation. Absorption and desorption conditions to a pre-conditioned solid phase micro-extraction (SPME) fibre with 85 µm carboxen/ polydimethylsiloxane (CAR/PDMS) absorptive coating (StableFlex, Supelco) were identical to Vervoort et al (2012). Thermal desorption and thermal cleaning of the fiber after each extraction was similar to the protocol of Vervoort et al, 2012, with modification that cleaning was 40 min at 300 °C in this study.…”

“…The shelf life of a high intensity PEF treated product is mainly determined by outgrowth of micro-organisms and remaining enzyme activity, although other chemical reactions can take place as well during the storage period, that can result into a loss of fresh flavour, degradation of ascorbic acid, cloud degradation and discoloration Vervoort et al, 2011;Vervoort et al, 2012).…”