Staff Publications

Staff Publications

  • external user (warningwarning)
  • Log in as
  • language uk
  • About

    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

    We have a manual that explains all the features 

Record number 549767
Title Moderate intensity Pulsed Electric Fields (PEF) as alternative mild preservation technology for fruit juice
Author(s) Timmermans, R.A.H.; Mastwijk, H.C.; Berendsen, L.B.J.M.; Nederhoff, A.L.; Matser, A.M.; Boekel, M.A.J.S. Van; Nierop Groot, M.N.
Source International Journal of Food Microbiology 298 (2019). - ISSN 0168-1605 - p. 63 - 73.
DOI https://doi.org/10.1016/j.ijfoodmicro.2019.02.015
Department(s) Food Technology
VLAG
Publication type Refereed Article in a scientific journal
Publication year 2019
Keyword(s) Electric field strength - Microbiology - Ohmic heating - Preservation - Pulse width - Thermal reference
Abstract

Moderate intensity Pulsed Electric Fields (PEF) was studied for microbial inactivation as an alternative to high intensity PEF or to classical thermal pasteurization. The process is characterized by the application of electric pulses, allowing an increase of the product temperature by the ohmic heat generated by the pulses. A systematic evaluation of the effect of parameters electric field strength (E) and pulse width (τ) on the inactivation of Escherichia coli, Listeria monocytogenes, Lactobacillus plantarum, Salmonella Senftenberg and Saccharomyces cerevisiae in orange juice was carried out in a continuous flow system. A wide range of conditions was evaluated, and both E and τ were shown to be important in the efficacy to inactivate micro-organisms. Remarkably, PEF conditions at E = 2.7 kV/cm and τ = 15–1000 μs showed to be more effective in microbial inactivation than at E = 10 kV/cm and τ = 2 μs. Inactivation kinetics of the tested PEF conditions were compared to an equivalent thermal process to disentangle non-thermal effects (electroporation) from thermal effects responsible for the microbial inactivation. At standard high intensity PEF treatment a non-thermal inactivation at E = 20 kV/cm and τ = 2 μs pulses was observed and attributed to electroporation. Non-thermal effects could also be resolved with moderate intensity PEF at E = 2.7 kV/cm and pulse width between τ = 15–1000 μs. Microbial inactivation at these moderate intensity PEF conditions was studied in more detail at different pH and medium conductivity for E. coli and L. monocytogenes in watermelon juice and coconut water. Under moderate intensity PEF conditions the effectiveness of treatment was independent of pH for all evaluated matrices in the pH range of 3.8–6.0, whereas under high intensity PEF conditions the pH of the product is a critical factor for microbial inactivation. This suggests that the inactivation proceeds through a different mechanism at moderate intensity PEF, and speculations for this mechanism are presented. In conclusion, moderate intensity PEF conditions at E = 2.7 kV/cm and pulse width of 15–1000 μs has potential for industrial processing for the preservation of fruit juices and pH neutral liquid food products.

Comments
There are no comments yet. You can post the first one!
Post a comment
 
Please log in to use this service. Login as Wageningen University & Research user or guest user in upper right hand corner of this page.