, Volume 11, Issue 4, pp 838–850 | Cite as

Comprehensive VOC profiling of an apple germplasm collection by PTR-ToF-MS

  • Brian FarnetiEmail author
  • Iuliia Khomenko
  • Luca Cappellin
  • Valentina Ting
  • Andrea Romano
  • Franco Biasioli
  • Guglielmo Costa
  • Fabrizio Costa
Original Article


Fruit quality is generally represented by several components, among which aroma plays a fundamental role in determining the overall appreciation. To generate a comprehensive data inventory of aroma compounds in apple, a large collection represented by 190 apple accessions was characterized by a proton transfer reaction-time of flight-mass spectrometry (PTR-ToF-MS) instrument, a valid alternative to a gas chromatography-mass spectrometry (GS-MS) apparatus. The analytical performance of this instrument allowed to profile volatile organic compound (VOC) spectra of a portion of apple fruit flesh in a short time and efficient manner. Based on the VOC composition, the collection resulted grouped into six main clusters, mainly determined by ester and alcohols. These two VOC categories were also further exploited for the definition of an Alcohols/Esters index, which can be considered as a novel fruit quality descriptor useful for a further and more exhaustive characterization of several apple accessions. The distribution of these compounds and the possible further use of these information are discussed.


Malus x domestica Borkh VOCs Esters Alcohols Aroma PTR-ToF-MS 



This work was supported by the Agroalimentare e Ricerca project (AGER Grant No. 2010–2119). Authors wish to thank Pierluigi Magnago and his team for the maintenance of the apple collection, and Marco Fontanari for his support in fruit sampling.

Conflict of interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Compliance with Ethical Requirements

This article does not contain any studies with human or animal subjects.

Supplementary material

11306_2014_744_MOESM1_ESM.pptx (182 kb)
Supplementary Fig. 1. VOC production of two apple cultivars, ‘Golden Delicious’ and ‘Fuji’. In panel “a” it is depicted the difference in volatile production (esters, alcohols, carbonyl, and other compounds) between harvest and after two months of cold storage of intact apples for both cultivars, respectively. In panel “b” it is instead reported the same comparison described for panel “a” but performed on cut fruits. Each volatile chemical class, measured by PTR-ToF-MS, and expressed in ppbv, is reported in the legend
11306_2014_744_MOESM2_ESM.pdf (600 kb)
Supplementary Fig. 2. High resolution heat map and two-dimensional hierarchical dendrograms of VOCs patterns of 190 apple accessions assessed by PTR-ToF-MS
11306_2014_744_MOESM3_ESM.pdf (23 kb)
Supplementary Fig. 3. Pearson correlations of the PTR-ToF-MS masses detected among the 190 apple accessions
11306_2014_744_MOESM4_ESM.pdf (69 kb)
Supplementary Fig. 4. High resolution bar chart of average values, plus standard deviation, of volatile content of apple accessions belonging to the six clusters determined by Ward’s cluster analysis
11306_2014_744_MOESM5_ESM.pdf (196 kb)
Supplementary Fig. 5. VOC profile comparison of healthy and watercore affected apples of cvs. “Jolly” and “Seriana”
11306_2014_744_MOESM6_ESM.pptx (57 kb)
Supplementary Fig. 6. PCA score plot of volatile compounds assessed by PTR-ToF-MS on apple accessions measured during the first (white circle) and on the second (filled triangle) year
11306_2014_744_MOESM7_ESM.pptx (55 kb)
Supplementary Fig. 7. Correlation chart of the first two principal components (panels a, b) and of the index of absorbance difference (IAD, panel c) of 12 apple cultivars (showing a correlation lower than 90 %) assessed by PTR-ToF-MS and DA-meter during two the harvesting seasons
11306_2014_744_MOESM8_ESM.pptx (59 kb)
Supplementary Fig. 8. Correlation between the variation in ripening (ΔIAD, year 1 and 2) with the PC1 (a) and PC2 (b) values
11306_2014_744_MOESM9_ESM.pdf (222 kb)
Supplementary Fig. 9. High resolution bar chart of the values of the AE factor (total alcohol content over the total ester content) of the 190 apple accessions
11306_2014_744_MOESM10_ESM.pdf (85 kb)
Supplementary Table 1. Subdivision of 190 apple accession assessed by PTR-MS into 6 cluster. Cultivar underlined are those assessed for the years consecutively
11306_2014_744_MOESM11_ESM.pdf (162 kb)
Supplementary Table 2. Variance analysis of each detected mass (threshold of 25 ppbv) for the six apple clusters
11306_2014_744_MOESM12_ESM.pptx (42 kb)
Supplementary Table 3. Table of the percentages of volatiles statistically different (P < 0.01) between each clusters based on pairwise ANOVA analysis


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Brian Farneti
    • 1
    Email author
  • Iuliia Khomenko
    • 2
  • Luca Cappellin
    • 2
  • Valentina Ting
    • 2
  • Andrea Romano
    • 2
  • Franco Biasioli
    • 2
  • Guglielmo Costa
    • 1
  • Fabrizio Costa
    • 2
  1. 1.Department of Agricultural SciencesBologna UniversityBolognaItaly
  2. 2.Research and Innovation CentreFondazione Edmund MachTrentoItaly

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