Authentication of pineapple (Ananas comosus [L.] Merr.) fruit maturity stages by quantitative analysis of γ- and δ-lactones using headspace solid-phase microextraction and chirospecific gas chromatography–selected ion monitoring mass spectrometry (HS-SPME–GC–SIM-MS)

Abstract

Headspace solid phase microextraction and chirospecific gas chromatography–mass spectrometry in selected ion monitoring mode (HS-SPME–GC–SIM-MS) allowed quantitative determination of δ-lactones (δ-C8, δ-C10) and γ-lactones (γ-C6, γ-C8, γ-C10). A stable isotope dilution assay (SIDA) with d7-γ-decalactone as internal standard was used for quantitative analysis of pineapple lactones that was performed at three progressing post-harvest stages of fully ripe air-freighted and green-ripe sea-freighted fruits, covering the relevant shelf-life of the fruits. Fresh pineapples harvested at full maturity were characterised by γ-C6 of high enantiomeric purity remaining stable during the whole post-harvest period. In contrast, the enantiomeric purity of γ-C6 significantly decreased during post-harvest storage of sea-freighted pineapples. The biogenetical background and the potential of chirospecific analysis of lactones for authentication and quality evaluation of fresh pineapple fruits are discussed.