Food and Bioprocess Technology

, Volume 6, Issue 10, pp 2831–2843 | Cite as

PTR-ToF-MS, A Novel, Rapid, High Sensitivity and Non-Invasive Tool to Monitor Volatile Compound Release During Fruit Post-Harvest Storage: The Case Study of Apple Ripening

  • Christos Soukoulis
  • Luca Cappellin
  • Eugenio Aprea
  • Fabrizio Costa
  • Roberto Viola
  • Tilmann D. Märk
  • Flavia Gasperi
  • Franco Biasioli
Original Paper


In the present study, the potential of PTR-ToF-MS for addressing fundamental and technical post-harvest issues was tested on the non-destructive and rapid monitoring of volatile compound evolution in three apple cultivars (‘Golden Delicious’, ‘Braeburn’ and ‘Gold Rush’) during 25 days of post-harvest shelf life ripening. There were more than 800 peaks in the PTR-ToF-MS spectra of apple headspace and many of them were associated with relevant compounds. Besides the ion produced upon proton transfer, we used the ion at mass 28.031 (C2H 4 + ) produced by charge transfer from residual O 2 + as a monitor for ethylene concentration. ‘Golden Delicious’ apples were characterised by higher ethylene emission rates than ‘Gold Rush’ and ‘Braeburn’, and quantitative comparison has been supported by two segment piecewise linear model fitting. Ester evolution during post-harvest ripening is strongly dependent on endogenous ethylene concentration levels. For ‘Golden Delicious’ and ‘Braeburn’, sesquiterpenes (alpha-farnesene) exhibited a fast response to ethylene emission followed by a rapid decline after the endogenous ethylene maximum peak. Carbonyl compounds displayed a different time evolution as compared to esters and terpenes and did not show any evident relationship with ethylene. Methanol and ethanol concentrations during the entire storage period did not change significantly. We show how multivariate analysis can efficiently handle the large datasets produced by PTR-ToF-MS and that the outcomes obtained are in agreement with the literature. The different volatile compounds could be simultaneously monitored with high time resolution, providing advantages over the more established techniques for the investigation of VOC dynamics in fruit post-harvest storage trials.


PTR-ToF-MS Volatile compounds Apple (Malus × domesticaClimacteric post-harvest ripening 


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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  • Christos Soukoulis
    • 1
    • 3
  • Luca Cappellin
    • 1
    • 2
  • Eugenio Aprea
    • 1
  • Fabrizio Costa
    • 1
  • Roberto Viola
    • 1
  • Tilmann D. Märk
    • 2
  • Flavia Gasperi
    • 1
  • Franco Biasioli
    • 1
  1. 1.Research and Innovation CentreFoundation Edmund MachSan Michele all’ AdigeItaly
  2. 2.Institut für Ionenphysik und Angewandte PhysikLeopold-Franzens Universität InnsbruckInnsbruckAustria
  3. 3.Division of Food SciencesUniversity of NottinghamLoughboroughUK

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