Use of TD-GC-TOF-MS to assess volatile composition during post-harvest storage in seven accessions of rocket salad (Eruca sativa)

Abstract

An important step in breeding for nutritionally enhanced varieties is determining the effects of the post-harvest supply chain on phytochemicals and the changes in VOCs produced over time. TD-GC-TOF-MS was used and a technique for the extraction of VOCs from the headspace using portable tubes is described. Forty-two compounds were detected; 39 were identified by comparison to NIST libraries. Thirty-five compounds had not been previously reported in Eruca sativa. Seven accessions were assessed for changes in headspace VOCs over 7days. Relative amounts of VOCs across 3 time points were significantly different - isothiocyanate-containing molecules being abundant on 'Day 0'. Each accession showed differences in proportions/types of volatiles produced on each day. PCA revealed a separation of VOC profiles according to the day of sampling. Changes in VOC profiles over time could provide a tool for assessment of shelf life.

Keywords: (E)-2-pentenal (PubChem CID: 5364752); (E)-4-oxohex-2-enal (PubChem CID: 6365145); (E,E)-2,4-hexadienal (PubChem CID: 637564); 1-Isothiocyanato-3-methylbutane (PubChem CID: 79086); 1-Penten-3-ol (PubChem CID: 12020); 1-Penten-3-one (PubChem CID: 15394); 2-Methyl-2-butenal (PubChem CID: 5321950); Brassicaceae; Diplotaxis tenuifolia; Eruca sativa; Gas chromatography mass spectrometry; Hexyl-isothiocyanate (PubChem CID: 78120); Iberverin (PubChem CID: 62351); Isothiocyanates; Pentyl isothiocyanate (PubChem CID: 69415); Rocket salad; Rucola; Volatile organic chemicals.